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In all the books and frequently on the list, mention is made that the 60 degree point on your depth indicator can be quite fragile and needs to be in good condition in order to remain accurate.  I haven't seen any discussion on the list that would give me an idea of how frequently most of you are replacing your points.  I'm sure some of you bought your first and only point from Noah's Shipbuilding and Industrial Supply - no financial interest.  (Sorry, I couldn't resist that one.)  Others, I'm sure, may go through several a year.

So, how often do most of you replace your points so I can get a feel for how "expendable" 60 degree points are?  (Tim Wilhelm)

I use the beefy 60 degree point that Russ at Golden Witch sells, I replace them once or twice a year, which is probably more than I need to. I would replace them often if I were using the small points that come with indicators.

Avoid the temptation to slide the indicator down the forms, that definitely saves on wear and tear, not just on your tip but the indicator base as well.  (Shawn Pineo)

Ahhhh Shawn!  You nailed me dead to rights on the bad habit I had developed - sliding the indicator down the form.  I had already decided that was not a good practice and won't now that I have a new point on the indicator.

I'm building a new planing form and being really anal about accuracy this time.  As I was filing the groove I was getting some depth readings that just didn't seem right.  Nothing specific, just didn't seem right.  So I decided to change points and that is when I got to wondering about their durability and life span.

Thanks for your input on this.  (Tim Wilhelm)

The first and only one I bought, 6 years ago or so. It has been on the business end of my depth gauge ever since, which sits bolt upright on the shelf over the workbench, point down into a pine board shelf. It doesn't seem to have suffered any, when I set my forms with it and plane a strip down flush to the form, the strip measures just what it is supposed to. I presume that to mean that either the point and my dial caliper are both accurate, or they are off by the same amount.   (John Channer)

What I do is find out how much the tip is off. I use the drill rod and form method to determine what the actual depth of the form is then I use the 60 degree tip to measure and check to see if it is off. I have a tip that is off by .002" and it is easy enough with this method to calibrate the dial indicator so it is  dead on. I mean who want to wait to get a new tip when in the middle of a project, when you can actually determine how to compensate for it. I check my tip every time I set a form.  (Adam Vigil)

To me the condition/accuracy of the sides of the 60° point are more important than how sharp the point. The different methods of calibration of the DI tells us where depth of the theoretical point is located. So, with reasonable care the 60° point should last for years.  (Don Schneider)

The point of the point is pointless!!! (Couldn't help it guys, I'm an inveterate punster)

You don't measure ANYthing with the point. As Don says, it's the sides (shoulders) of the tip that matter. Think about when you actually closed your forms completely and (maybe) involved the actual tip in a measurement... I bet it never happened. Since the doohickey rests on its sides all  the time  (when it's in the groove), you shouldn't need another for a looong time. Use trig to set up the "tip" and you can recheck that every now and then and it'll do the trick.

I have a new computer and new e-mail software now, so I can't just forward the original post of this, so here goes.

Drill a 1/8" hole in a piece of metal with a GOOD drill; if its point isn't centered it's not going to give a true 1/8". Heck, it might not be a bad idea to put it at the very end of your forms!

When the V of the tip is sitting centered in that hole the point (if there WERE an actual exact point) on it would be .108 deep into the hole.  (That's from the trigonometry of the equilateral triangle. The altitude is the sine of 60 degrees X a side's length, .125) If you set your point to zero while having it sit ON the flat of the forms and it doesn't say ".108" , your point isn't a true point (Might have been when new, but not any longer: also, be aware that I believe some manufacturers actually "relieve" the point by several thousandths in its construction, so it never WAS a point)

Reset the dial to .108 and now you've constructed a virtual point on the end of the tip so when it says "zero" on the flat, it'll be accurate relative to what your V is, set to in the forms. That is, when the rounded point you have sits on the forms it'll say 000 and when it says .097 in the forms, the .097 will be .097 BELOW the surface of the metal.

I can do a trig derivation of this if there's a real demand, but I ain't agonna do it without somebody whining about it first *G*. It involves drawing diagrams on this thing and that ain't no picnic!

Don't be afraid to ask questions.  (Art Port)

I understand that we are measuring what is a theoretical bottom of the groove and as Don has suggested, we could use a blunt point, since our measurements aren't less then .010.  The important part of the point is the shoulder which is far more durable than the actual point.  As you might have noted from my reply to Shawn earlier, he has uncovered my dirty little secret that I developed a nasty habit, now stopped, of sliding my indicator down the form.  My point currently shows wear on the shoulder of it and I have replaced it with a spare I have.  Even using good practices and care, though, I would imagine, with time that any point would wear on the shoulder and accuracy ultimately suffer.

My original question was directed at what could be considered the useful life of a 60 degree point based on normal wear and tear.

Some of the responses I have received indicate that if I would use my tools correctly, (not likely) I can expect to pass them on one day to my grandchildren.  Won't they be happy! 8^))

As far as calibrating the indicator, I use the method you describe.  I have a piece of steel with a 1/8" diameter. hole.  I drilled it undersize and then used a 1/8" reamer to attempt to make it more accurate.  I also use a test block that I got from Jeff Wagner.  I set to one and verify with the other.  (Tim Wilhelm)

I'm afraid that, after 6 years of hash and rehash on this subject, I still don't see the reason for all the fuss. Set your forms, plane your first strip, measure it where the form adjustments are, if not the same, reset the form accordingly. If you zero the depth gauge on whatever flat surface is handy, such as the top of the form,  even if the point is round, flat or whatever, the strip will never be smaller than the intended dimension and a few thousands change in the form will be the same no matter what shape the end of the tip. Oh, well, I've tried and that's all I can do, choose your own paths to terminal retention, LOL.  (John Channer)

The point on the 60 degrees is only good if it is perfect. It is hard to keep it that way so I don't use the point tip at all. Set your calipers to .1155. Set the point in the .1155 space with the block flat on the caliper jaws,  zero the depth gauge. This will give you accurate readings of the groove  depth.  (Tony Spezio)

I need sources & what should I expect to pay for a dial indicator depth gauge?  Also I have dial calipers, do I still need a micrometer?  (Brad Bireley)

Check Golden Witch or Wagner Rods.  Can get the indicator from Harbor Freight, the base from Golden Witch or Wagner Rods.  (Pete Van Schaack)

And if you wish to go the cheap route try   Enco -- The Right Tool At The Right Price!   (John Freedy)

You'll need a dial indicator, 60 degree point for the indicator, a base for it and some way to accurately set the indicator.  You can buy the bits 'n pieces from Grizzly, Starrett, Enco, Harbor Freight or other machine tool suppliers. Russ Gooding (Golden Witch), Jeff Wagner both sell dial ind./depth gauge kits w/ everything included.  John Long is also selling a rod makers depth gauge kit. John's kit has a 0-.500 dial indicator, a large solid brass base, a 60 degree point made of tool steel hardened to Rockwell C60-63 and a calibration fixture using parallel bars of precision ground, polished drill blanks hardened to Rockwell C64. I don't remember what John is charging for the kit. No commercial interest yadda yadda yadda  (Dennis Higham)

Re: micrometer, it depends on your dial caliper.  If it reads in .001",  no you don't need a mic.  If your caliper reads in 1/64", you need something that reads to .001, be it another caliper or a micrometer.   (Neil Savage)

One of my favorite suppliers is Penn Tool (don't get it confused with Penn State Tool -- the dust collector people).  What I like about Penn Tool is that in addition to selling  Starrett, Mitutoyo, Brown & Sharpe, and Fowler they also sell a brand (not a house brand) called SPI or Swiss Precision Inc. most of their measuring and cutting tools are made in Switzerland and are comparable or higher quality than Starrett but generally lower in price.  Check country of origin as a few of the newer SPI tools are coming out of Taiwan (which does have a good reputation for tool quality) and make sure you don't overpay.

For people with South Bend Lathes, the SPI 3C collets are second to NONE (including Hardinge).

Usual disclaimers apply.  (George Bourke)

A few of you have mentioned the Golden Witch base. I am new to rodmaking and I have purchased one myself.  It is  high quality, but I really am having difficulty reading this bugger. I have set the gauge/base up to the standard, which in my case is .398 deep. The rev counter on 7, the dial at zero. The concept of deducting 3 from the rev counter or .300 from the dial reading to read the actual depth (according to the paperwork that came with it) is confusing to me. By playing around with it, I've created a situation where I think I'm getting to the end, but don't understand how I'm getting there. Other rodmakers have told me not mess with this theoretical depth thing, just zero the point on the forms. I really don't want to do that. I know most of you don't, and besides I would like to take full advantage of what I paid for. Can anyone please shed some light on this? It is one of those brain damage things that wakes me up at night.  (Tom Vagell)

Having been in your same situation, I ran into Russ at the NJ fly fishing show, and showed me how to set it up and use it, yes it is brain damaging! Like my old algebra would say “don’t try to understand it, just except it” Call Russ, and I’m sure he will “talk you through it” Or Ken @ Golden Witch.  (Pete Van Schaack)

The easiest way to set the indicator is the set your calipers at .1155. Lock it there Set the block on the gap in the calipers with the 60 degree point in the gap.  Set the dial on the gauge to Zero. That is it. You may want to get what you paid for but why fight it.  (Tony Spezio)

I think I was the first to advocate precision pins and a depth Mic to set the forms.  It is a very precise method and is described in The Best of the Planing Form.  It is also slow, and I caved in a few years ago and now use a dial indicator and base.  I still use the pins and depth Mic to check and/or reset the dial indicator.  The dial indicator point I use is a commercial item  and superficially looks very accurate.  However when its checked against the pin method I found it was .008" short of having a "perfect" point.  This means that if I zeroed it on the top of the form every strip would be .008" oversize and the glued up section would be .016" oversize, the equivalent of about two line sizes.  I made my dial indicator base on my lathe and counter bored the base to receive a donut-shaped magnet.  This keeps the base securely in place on the form and almost eliminates the chance of knocking it off the work bench.  I got the magnet from Lee Valley.  (Ted Knott)

Would you not be able to "discover" your oversize strips when measuring the finished strip and compensate for it then?  I'm not familiar with the precision pins so this question may be not be warranted.  (Brian Thoman)

Yes, you could discover the actual error by measuring the planed strip, then reset your forms and plane again to get it right.  But I'd rather do it right the first time.  (Ted Knott)

You guys are just going thru all this form setting stuff again just to drive my blood pressure thru the roof!! LOL. Ignore the little dial with the rev counter, it's irrelevant. Put the indicator in the base, set it on something good and flat, such as the top of your planing form and set the main dial to 0. Now mark your first strip at every station and plane it, measure what you get and reset the forms as necessary, you will NEVER plane a strip too small, it can only be too big. After the first rod or two, you will know what the difference is and set your forms accordingly without having to fuss over it. I have had to set mine .002 under for 6 years without variation. If you keep your indicator point down on a piece of softwood, such as a pine shelf, the point will stay as it was when you bought it. Time for my meds.  (John Channer)

Is there an easy way to make your own depth gauge base and as a first timer is there a particular brand or type I should buy?  (Daniel Durocher)

Starrett, Brown & Sharpe, and Mitutoyo are the most reliable brands.  Of these, Mitutoyo has the best warranty service and parts availability. Cheaper brands will probably work fine, but you won't get the peace of mind.  (Tim Preusch)

If you have a lathe, it's relatively easy.  I made my own, and made one for Don Schneider too.  The hard part is finding the brass stock in 2" thick chunks without breaking the bank or remortgaging your home...  (Mark Wendt)

I have made a number of them from aluminum stock.

I used rectangle stock purchased at the local metal place. It is pretty square to start with. Have them cut you off a 2' length of 1"X 1 1/2" stock. Clean up the burrs on some  240 sandpaper. Check it for square on the bottom. On the top, mark the center and drill a 3/8" vertical hole to accept the gauge. If the gauge body is smaller or larger than 3/8" drill accordingly. Do this in a drill press to get the hole square with the base. On the backside, drill and tap a hole for a 6 or 8 thumbscrew to lock the gauge in the vertical hole.  (Tony Spezio)

One more question.  How high a resolution (if that is the right term) does a rod maker need in a depth gauge. Do I really need to spend $200.00 Canadian to get one.  (Daniel Durocher)

I bought my first from Lee Valley Tools ($20 CAN).  It was recommended by a maker friend here in Calgary - he used it until his untimely passing away earlier this month.  Then I came across the Mitutoyo 2904F From Thomas Skinner in Calgary ($100 CAN).  Both have a 1" depth and the dial  is measured  in 1 thousandth increments. The Lee Valley Model measures "inwards" and the Mitutoyo measures "outwards".  I prefer the latter.  I set the guage to zero on the top of my form and it measures from zero as the point goes down into the groove, giving a "positive" measurement (IE: the measurement is greater than zero).  With the cheaper Lee Valley gauge, the reading was "negative" (IE: less than zero).  I prefer the Mitutoyo.  I thought $100 CAN was OK for that benefit.

On a similar track - I bought a 60 degree point for the Mitutoyo from Thomas Skinner as well (about $10 Canadian I think).  Don't.  Get the oversize point from Golden Witch.

Then there is the Mitutoyo 1156 model (just called them - on sale at Thomas Skinner till March 1 at $90.77 - and no, I don't have shares there, but I should, given the trade they do with me  [:)] This one has the measuring "plunger" perpendicular to the dial face - seems way easier to read!  Yes, I will be buying one soon...  This is featured on the rodmakers site I think)  (Greg Dawson)

I have a $150.00 Starrett that reads the same as my Harbor Freight $14.00 gauge.   (Tony Spezio)

I'm wondering where I can find a 60 degree dial depth gage tip.  I can't seem to find it on the Net or in catalogues.  Maybe I'm not calling it by the right name.   Anyone know of an commercial source?

Also, what about a commercial source for a "standard" to calibrate my depth gage?  Any sources for this item?

My bamboo shop is just about setup for the first rod (and I'm just about completed with my PHY Driggs River at Chris O's place. I'm itching to get out on my own and goof things up (without a safety net!).   (Scott Turner)

Starrett makes a 60 degree point.  I don't have the model with me right now.  You can call Starrett and then they'll point you to a supplier.  That's how I did it.  I think I bought from MSC.  They ran about $3.50 or so.  (Lee Orr)

Don't overlook the drill rod method.  There's a good write-up on it here.  (David Bolin)

You can use this method that I copied off the tips section or spend the money for a standard. JD Wagner has them.

"Set your calipers to .1155. Set the 60 degree point in the .1155 caliper gap with the indicator block flat on the caliper blades. Rotate the face of the dial indicator to zero, tighten the face set set knob."  (John Freedy)

I really can't believe I didn't think about Golden Witch.

I'm a little bit lost on how setting the calipers to .1115 makes a zero setting. I'll look in the tip's section (I had looked through a few times already for this information, but didn't find this information).  Unless anyone wants to take a crack at explaining this concept to a moron like me?  (Scott Turner)

For those who use a digital depth gauge to set the planing form, how do you calibrate the indicator? The dial caliper method -- set caliper to .1115, set indicator point between the jaws of the caliper, and zero indicator -- does not appear to work. (It does work with a mechanical depth gauge.)  (Paul Franklyn)

I use feeler gauges equivalent to the error, and zero the indicator on a flat surface with the feeler gauges under the point.  (Larry Blan)

Good idea on the feeler gauge, Larry.  I think that will work with the inexpensive digital indicator I have. It allows me to zero the indicator on a flat surface (or change from inches to mm), but I cannot change the digital reading to match a predetermined depth on a machined standard, or when using the dial caliper method. I can't explain why this type of digital indicator does not work with the caliper method (with caliper set to .1155), but it doesn't render a coherent reading like a mechanical gauge that is rotated to zero.  (Paul Franklyn)

Somebody please remind me why it has to be more complicated than setting the depth gauge on top of the form and turning the dial to "0". I've been doing it that way for 53 rods with the same indicator with the same point on it and when I measure the strips at each station, they still are the same measurement I set the form at.  (John Channer)

It doesn't, unless you are using a digital gauge. My dial turns, but it only turns the display! There are certainly digital indicators that allow the zero to be set to any dimension, but they tend to be expensive. In addition, I zeroed it once. It will hold that zero until I change the batteries, no need to zero it again! I'm with you on the point though, mine hasn't changed a bit, and the indicator reads in .0005 increments.  (Larry Blan)

That's the way  I had been doing it also John. I was afraid to chime in and look bad. *G*   (Dewey Hildebrand)

I use a piece of flat glass to zero out on.  I figure the steel HAS to be harder than the glass.  It also matches up with my Standard and agrees with the .1155" caliper test, etc.

All's well that ends well.  (Scott Turner)

No indicator point is a perfect point; it's rounded, however slightly, and that introduces error into the process. THAT's because we're almost never using the actual point to measure our forms' depth. The forms aren't a true vee, they're a virtual V. The point of your indicator hits bottom only at the first station, and then only if the forms are totally cranked closed. Thus, since you're measuring using the "shoulders" of the indictor's "point" you're never referencing off the rounded tip of it anyway. That's why the setting gauge is better. It tells you where that virtual point (of the indicator) is,  relative to to slopes of the sides.

The best way I can suggest you see what I mean is to draw an inverted 60 degree cone with a rounded end, and a true pointy cone. Now draw a 60 degree V, erase the bottom, and place both of your "points"  into it.

See how the rounded one, when sitting on a  flat surface, would say "zero" at a different setting?

Hope I've made sense.  (Art Port)

Yes, that's the theory.  However, we are talking in practical terms here (aren't we?)  If setting the tip on a flat surface works within the limits of accuracy we are looking for, why not use that method?  If we were talking microinches, I'd agree the flat surface method isn't "good enough", however it works for me and I can't measure the difference between setting mine on a flat surface and in a .1155" hole or with the caliper method.  (Neil Savage)

As I understand it, that radius can cause the virtual point and the tip of the indicator to differ by several thousandths. If you use the indicator as a rough setup tool and then a differential measuring tool, it'll all work out in the end.

I basically set up my forms using the indicator, measure a couple of strips that result, and then use the indicator to change the settings by whatever thousandths I'm off. For that, the type of point really doesn't matter. If the cane is .075 and that's .003 to big, I set the indicator in the form and whatever it reads, say .067, I tighten the forms to read  -.003 or .064.  (Art Port)

You're right!  Furthermore, when using calipers set at .1155 to calibrate you are introducing error as well.  The edges of the caliper jaws are not razor sharp.  They have a slight "break" on them so you don't cut your fingers but that radius increases the "apparent" gap when inserting a 60 degree point.

I use a hardened steel 60 degree Vee block with a tiny groove at the bottom to clear the 60 degree point.  I calibrated the depth using the dowel pin and micrometer technique. This exactly imitates a planing form.  (Al Baldauski)

I read somewhere, that anything that had an edge, had a radius. The smaller the radius, the sharper the edge. I suspect planed bamboo strips have no radius, is why they are sooo sharp! My planing forms were made, using a dial indicator with a homemade 60° point, calibrated on a flat surface. Yep, about .010 short, making the groove about .008-.010 toooo deep! Worked the forms down with a belt sander. Loong story! Counting the rods that were trashed, over 50 made and still being used. I calibrate with a short piece of planing form. Strips actually planed, measured, and glued together and mic'd again. A lot of trial and error, till I found a set of numbers that worked. To measure the strips, I filed small 60° grooves in one jaw of my dial caliper. More trial and error to calibrate them. How accurate is it, probably way off, but I end up with target numbers on the finished rod!  (David Dziadosz)

Your point may be rounded, but mine is still sharp as the day it was made! Seriously, I keep it either laying on it's side or on a wood shelf, so it hasn't worn all that much. As I've said before, measuring your first strip will tell you what you need to do to the settings anyway. I find life to be a series of errors anyway, so one more or less doesn't bother me much.  (John Channer)

I agree.  I mean the point on my indicator has never bent, but of course I don't have the  engineers mentality. I guess if I used an electron microscope I might be able to tell.   (Bill Tagye)

It's really easy to make a setting standard.

What you'll need is:

Use your oilstone to flatten the block on one side. 

Locate where you want the hole.  I used 1&1/4" from the edge in both directions.

Drill through with the .050 drill bit.

Zero your indicator on a flat surface without the 60-degree point.  You want to be able to measure how much the ball protrudes above the block surface.

Slowly, carefully drill the 60-degree hole with the router bit.  Stop often and put the ball in the hole and check how much it protrudes with your indicator.  You want the ball just flush with the surface of the block and no more.

When   you  have  the  ball  flush  with  the  surface  (I  try  for ± .0005"), then the hole depth will be 1.5 times the ball diameter.  If you used a .100 ball then the hole will be .150.  Actually, my standard has a couple 60 degree holes, one .150" deep and one .234" deep.  Mark the block with the depth of the hole.

Put the 60-degree point back on your indicator, and adjust it to read the value you marked on the block.  (Ron Larsen)

I didn't answer your question, did I?  Sorry 'bout that.

I use a Sylvac digital gauge and as the plunger goes away from the body it has to read negative.  The Sylvac has the provision to change the sign of the reading.  Possibly this is the problem with your digital.

The Sylvac also has the provision to set two reference distances.  I have mine set to -.150 and -.234.  (Ron Larsen)

I think you have identified the problem. My digital gauge does not have the ability to set a reference point other than zero. So inexpensive means cheap. But I will make it work with Larry Blan's idea.  (Paul Franklyn)

Fascinating process! 

I'm adding this to the other dozen ways to calibrate a dial depth indicator / how to make a standard. 

I'm always impressed to hear different ways to attack similar problems.  I think that is what drives innovation.  (Scott Turner)

I think a lot of rodmakers have the engineers mentality. And that's  OK, they seek perfection and like the math. For a guy like me that has trouble  making change for a dollar. I put the point to the flat surface, set it at 0. Adjust my forms. Plane one strip, measure the strip, then adjust the forms + or - and I'm right on target. I find that I'm off .003 to .005 on the plus side every time using the this method. Not bad for two years of general math in high school!  (Bill Tagye)

My method is much the same, Bill. I read somewhere that .004 is the usual "flattening" of the point and allow that when setting the form. Yours seems about the same.  (Ian Kearney)

I checked mine today and got an error of about .0025 and given that it is a new point that's not bad I guess.  (Larry Puckett)

I forgot where I got my point, been six plus years.

Where is the best place to get them. I talked to J&L twice several months ago , they said they would call back with info. Never got a call back. Have a couple of other gauges I would like to set up.  (Tony Spezio)

mscdirect.com was the best place to get this. The part number is 6632-6 Steel Starrett Contact Point.  Apparently it is special order, because the web site now presents:

Part #: 66326 (00663260)

The MSC Part Number that you entered is not available for purchase on the web site. Please call 1-800-645-7270 FREE for more information on this item. One of our Customer Service Associates will be more than happy to assist you.  (Paul Franklyn)

For those interested, the actual mscdirect.com part number is 86429800 and they are in stock.  Cost is a little over $4  (Jim Brandt)

I called MSC today. The 86429800 is a set of points that include a 60 degree point.  No problem on that if you can use the other different points.  In Paul's message, the the 66326 is now Part # 06444459 this is a 1/2" long 60 degree point with a 4 /48 thread @ 2.29, they are in stock.  (Tony Spezio)

Some years ago I made a simple rig to measure the truncation of the tips of the Starrett 60 degree points I had.  This may help you calibrate your digital depth gauge.

You can make a standard with a 60 degree conical hole as I described earlier.  In another location on the flat surface drill and tap a hole for a set screw.  I'd use a #10 or larger.  Also, use a nylok set screw so it won't move.  Hone a flat on the tip of the set screw.

Screw the set screw up from the bottom of the standard until it's flush, set your depth gauge over it and zero.  Now check the 60 degree standard and note the amount it's off from theoretical.  Set the depth gauge over the set screw and screw it up by the noted amount.

Re-zero the depth gauge and check the 60 degree standard.  It should be dead on.

Now you can zero your depth gauge on the set screw with some certainty of accuracy and if the point wears or you have to change points you can readjust.

My good Mitutoyo point is short by .0034 and my Starrett point is short by .0085.

We engineers have always been eccentric......

"I don't suffer from insanity, I enjoy every minute of it."  (Ron Larsen)

Try making one from a point with a blunt tip. That's how I started out. I couldn't find one, so made it out of a point with a blunt tip on a drill press, file, hone and a thread gage. Crude, but it worked, once I figured out how much of the point was missing and got it calibrated. After I got a lathe, I had bought a bunch of the cheap black 60° points. I checked them on the lathe and couldn't believe how much they varied. I trued them with the lathe. Much better now!  (David Dziadosz)

I made my first one from a blunt point and used it for several rods before I got a good one. Would like to get a few more of the "good" ones. Thanks for the info, if need be, I would make them from cheapies. I would rather not mess with it.  (Tony Spezio)

Can't argue with results. Some get them one way, others approach it from a different direction.

I've spent a lifetime in vehicle development, in one capacity or another. We have an old saying; "measure it with a micrometer, mark it with a crayon, and cut it with an ax". Sometimes, I think the entire process of building a rod fits that description pretty well.   (Larry Blan)

I love that quote Larry.  I think it applies to my rodmaking very well (and most of my other wood working projects). 

I like to make fun of myself and say I measure twice and cut four or five times.    (Scott Turner)

Try this method.

Get two ground dowel pins either 1/8,../ or 1/4 diameter. The size  is not critical but you must use pins of equal diameter.  Measure the  diameter of the pins with a micrometer and record the reading. Clamp them  together on a surface plate. Set indicator with a 60 degree point on the pins  with the 60 degree point resting on both pins. The depth is equal to the radius of the  pins  divided  by  2  multiplied  by  the  square  root  of  3 (1.73251). No muss, no fuss, no holes to drill or tap or otherwise shape. Pins can be attached to a block of steel to make a permanent standard.  (Jerry Andrews)

I am ready to take the plunge and start making rods. I have been repairing/restoring rods for several years, but now I want to make my own.

I am acquiring the necessary tools: I have the steel bars to make a form and the planes. I need a depth gauge & this leads me to my question: there is a Mitutoyo depth indicator on eBay, Item number: 290058616886, that looks like I could use. Is this suitable or should I go the price and buy a Golden Witch set?  (Pete Peterson)

For what it's worth, I find the $15-30 ones from Woodcraft, Grizzly and or Harbor Freight are accurate enough for rodmaking.  If you have a lathe, you can make a base.  You still need a 60 degree tip, but the extra .0005" accuracy in the Mitutoyo indicator itself is not necessary.  You can either read the red numbers on the inexpensive indicators, or pry the face off and renumber with a label maker or print numbers on a sticky label on your PC.  I think I paid about $10 on sale for one at H-F on sale that seems plenty accurate for rodmaking.  Really good instruments are nice if you can afford them, but if you're on a budget the others seem to do the job. 

Remember, if you mic a "classic" rod you will find variations of several thousandths from flat to flat at any particular place along the length.  They still catch fish.  (Neil Savage)

Still a newbie myself but have final planed about a half dozen rod sections so far on my own homemade maple forms. I used an $8 made in china dial indicator stuffed in a maple cutoff from my forms with a hardware store thumbscrew threaded into the side of the block as a depth gauge in making the forms. I have since acquired a Baker made in India depth gauge off eBay for $26 (one like it just sold for $20). Both work the same except the homemade one needs to be read backwards. Biggest expense was for two Starrett 60 degree points, since they were something like $30 with shipping through Grangers. Mitutoyo is good and the Golden Witch is tops, I'm sure, but my planing is still the biggest error on my strips.  (Joe Hudock)

Another reason to use the cheap "made in China" indicator is the first time it goes on the floor and you need a new one anyway it doesn't hurt nearly so much.  (Neil Savage)

Several years ago I dropped my DI. The tip broke off and the shaft was bent. I ordered a new DI and while I was waiting I thought "What have I got to lose?" They are not that complicated, so I took it apart, straighten the shaft. The hardest part was getting the broken stud of the point out of the shaft. Used a dental pick to unscrew it. Cleaned it up and now can't remember which one I dropped. They both work fine. Yes, they are both cheap ones.  (Don Schneider)

Unless you're using the rubber matting we discussed last week! There's nothing quite as nice as the soft rubbery sound of a "bounce" when any tool  I can  think of goes off the bench!  (Art Port)

I don't want to try it, but I wouldn't bet on the rubber mat saving a dial indicator.  (Neil Savage)

The rubber mat did not save mine last week. Glad it was a H.F. DI. and not my expensive one. Opened it up, the needle came disconnected,  and the small gear is stripped.  (Tony Spezio)

What I do is hook a bungee cord into the ring on the back of the Mitutoyo dial indicator, and when using it I just hang it around my neck;  not foolproof, I know, but it does give an extra level of fail-safe.   (Peter McKean)

After catching an indicator with my foot I went to a magnetic base. Blood pressure dropped 10 points when I'm using it.  (Henry Mitchell)

I've thought of doing that, but how do you know that the point is centered in the groove and not pulled to one side by the force of the magnet? I slide my base around and take the deepest reading to be accurate. You can't do that with the magnet, can you? I have worries   that   the   plunger   will   be off-center and the side of the point will be hung up on the wall of the groove. And therefore shallow.  (Art Port)

Or worse yet, your forms might get magnetized and then your plane will be stuck in place.  (Will Price)

What a cracking idea !

I am off to make mine now.  (Paul Blakley)

While you lose the convenient attaching point for your bungee, eliminating the lug back in favor of a flat back will make it much less top heavy, so it won't be quite as prone to toppling over in the first place.  (Larry Blan)

The gauge and base in that auction would be perfect for what you want to do. However, considering that it is sold "as is" makes me nervous. Drop one of those things once and it most likely is toast. You have received good advice in other posts regarding suitable depth gauges. You can get a 60 degree point from Golden Witch for $16  plus freight which should be around $5. If you want a Starrett you can get them fairly inexpensively  with a little looking. I have one virtually new I would sell for $10 including shipping (I like my Golden Witch point better). I just looked up the Golden Witch depth indicator package and at $345 more than a little steep even though it is the Cadillac of indicator setups.

While not necessary to the craft I recently bought a Lie Nielsen block plane. While I have 5 other planes this thing is easily 5 times better than anything I have used. If you are going spend some $ I would recommend this as far more valuable to your efforts than an expensive depth gauge.  (Steve Shelton)

I just finished rod #1 (Payne 101 taper) after taking Harry Boyd's class in Winnsboro, LA.  I have been reading the list e-mails for a few weeks and really appreciate the information offered by all.  I am in the process of rounding up tools and supplies to get started at home.  I wanted to see if anyone knows of a supplier for a 60 degree standard for a depth gage.  I have the gage, base and conical tip; just trying to locate a standard.  (Dan Smith)

Good to see your name pop up on the List.  You might check Jeff Wagner's standard and depth gauge out and see if Jeff will sell only the standard.  Otherwise the instructions on using the jaws of your calipers to set the depth gauge  work quite well.  (Harry Boyd)

You can set your dial calipers to .1155" and zero your depth gauge to zero with the calipers. It's what I do and it works real well for me.  (Ren Monllor)

Set-up your DI as Ren says. Drill any hole approximately .100" and measure what the DI says after zeroing it with Ren's method. Later when you want to calibrate your DI just put the 60° point in the hole and set the DI to the reading.  (Don Schneider)

Not to put to fine a point on it but using Ren’s method depends on the jaws of your dial caliper being razor sharp 90 degree edges.  Since you don’t cut yourself on the jaws you know the corners have some radius on them.  This effectively increases the “diameter” you’re setting.  It could amount to a few thousandths.  So you’ll have to double check against the measurement of a planed strip to be sure.

Additionally, you’re actually setting to  0.100 depth using this method.  If you’re using a dial indicator with a “turns counter” on it you have to be aware of where you’re setting the zero.

Using Don’s method to make a “standard” you have to be aware that when you drill a hole in metal you leave a sharp edge at the mouth of the hole.  If you don’t chamfer that edge slightly, each time you put your point in the hole (:-)) you flatten the sharp edge slightly and increase the effective diameter.  So chamfer the edge SLIGHTLY.  (Al Baldauski)

It's really easy to make a depth gage standard.

Here's how:

What you'll need to make a standard is:

Use your oilstone to flatten the block on one side. 

Locate where you want the hole.  I used 1&1/4" from the edge in both directions.

Drill through with the .050 drill bit.

Zero your indicator on a flat surface without the 60-degree point.  You want to be able to measure how much the ball protrudes above the block surface.

Slowly, carefully drill the 60-degree hole with the router bit.  Stop often and put the ball in the hole and check how much it protrudes with your indicator.  You want the ball just flush with the surface of the block and no more.

When you have the ball flush with  the surface  (I try for ± .0005"), then the hole depth will be 1.5 times the ball diameter.  If you used a .100 ball then the hole will be .150.  Actually, my standard has a couple 60 degree holes, one .150" deep and one .234" deep.  Mark the block with the depth of the hole.

Put the 60-degree point back on your indicator, and adjust it to read the value you marked on the block.  (Ron Larsen)

One of our very kind and helpful members made me a standard using this method and it made an immediate difference for me. Using the standard to zero my depth gage I was able to come within 0.001" of a station depth measured using Chris Bogart's test method. I then measured the smallest groove on my forms and matched the advertised depth dead on. I want to thank my benefactor but won't mention his name so he won't get inundated by requests -- he knows who he is.

This is the second time that I've been the recipient of this kind of help from a member of this board. Last time I was looking for a source of khaki rods bags and next thing I know several showed up in the mail. This is a great group and I look forward to a time when I can lend a hand to someone in need.  (Larry Puckett)

Open your calipers to .1155, lock it with the locking screw. Put the point in the jaw opening with the base flush on the jaws of the caliper. Set the indicator dial to zero. In reality you are reading .100 but the indicator is reading Zero. Now you can read direct off the face of the indicator.  (Tony Spezio)

I have used that for years and it really was a big help. I would go back and remeasure with drill rods and I found no difference. I remember you posting that tip several years ago. Thanks.  (Adam Vigil)

In theory this is a good method however, I found that because my base is rather large to give a stable footing on the forms it makes it difficult to get a reliable footing on the caliper jaws, which are rather small. Also on my calipers there is a small rise near the plastic case enclosing all the electronics which complicates the measurement. As a result I have not found this to be accurate. That's why I asked a few days ago about a calibration standard.   (Larry Puckett)

I made a standard from 1/2" drill rod.  I cut 2 pieces about 3" long (not critical at all) and epoxied them onto a piece of 1/8" aluminum I had in the shop.  I used J. B. Weld, ran epoxy along the rod on what became the outer edge of the standard and let it set, then tipped it up sideways a bit and ran epoxy down the outside of the other piece of rod.  This kept them together, though I did check a couple of times before the epoxy was fully set to be sure.  I set my dial indicator to read 0.183".   This is the best method I have found so far.  (Yes, I did the math.)  (Neil Savage)

I was wondering how do you set your dial indicator to zero.  (Brandon Shepelak)

There is only one truly reliable way to set a dial indicator to "zero" if you are using what I understand is the conventional setup for determining an acceptably accurate theoretical depth of a 60 degree (or any other) included angle "V" groove.

You need to have a groove of the angle that is of a known theoretical depth.  By that I mean that the literal depth of the "V", that is, the point of the apex, is not any indicator of the actual depth of the groove.  Cutters cannot maintain a literal "V" because of wear during the cut.  And the 60 degree "V" points that we buy are not, I repeat not, a sharp "V".  They can't be, because to be hardened there can not be any sharp edges to the metal, thus there is some rounding of the point for mechanical and metallurgical reasons.  And even if they were cut to a sharp "V", you can imagine how long that delicate point would maintain its less than human hair dimensional integrity while being rested on a hard surface.

To be tiresome, there must also be an accommodation for accumulations of whatever in the bottom of that literal "V", things like dust, dirt, oil, cat hair, you name it.  That requires a "dirt groove", something cut into every apex of every angle of a precision mechanical device, at least the internal angles like things like "V" ways and such.  So there is no literal bottom to the "V".

Get yourself a good standard.  Get yourself a good point on a good, really good indicator, and set it to the standard-maker's instructions.

Using a cylinder depth determination method is hairy, in that cylinders of truly accurate geometry are: a) expensive, and b) only as good as the linear location of the reading, to wit: measuring the crown of a sloping cylinder while bending over a dust-laden planing form while twiddling push-pull screws.

Good indicator points are readily available, as are standards for what we do.  If you are handy around a milling machine, you can make it as good as any body.  If not, there's a lot of amicable talent out there for the rodmaker.  (Wally Murray)

That depends on how crazy you want to make yourself over it. I find that I can zero mine on the top of the forms, plane my first strip until I no longer shave bamboo then check the measurements of the strip against the form settings and make any allowances. I've made enough rods now that I know what the difference is and set my forms accordingly and the strips come out where I want them. There are a lot more complicated ways to set you indicator, but in the end you are going by the measurements you get  from your caliper any way.  (John Channer)

Buy yourself a calibration block. Ron Grantham was talking about having a bunch made a week or so ago. Maybe he will respond. At any rate I tried all the various methods using my micrometer, measuring the thickness of the forms and a drill bit, zeroing on the forms, etc., and none of them worked consistently. Then I got a calibration block and hit my first measurement dead on balls accurate.  (Larry Puckett)

I believe that it was Barry Grantham not Ron Grantham that was going to make up the calibration blocks for Dial Indicators.  (Dick Fuhrman)

I am looking for a 60 degree point for my dial indicator, I am told that Starrett makes one, but am having trouble finding it. Does any one have the part number for it?  if not does any one have an alternative?  (Joseph Freeman)

Golden Witch also sells a 60 degree point, it is a bit wider than the Starrett point. I have both and prefer the one from Golden Witch as it is larger than the Starrett point.  (Don Green)

Check periodically to be sure the point hasn't unscrewed a bit from the stem of the indicator.  Don't ask how I know this...  (Neil Savage)

You won’t have to check so often if you remember to NOT drag the indicator along the forms as you measure from station to station.  (Ralph Tuttle)

I know that.  I just don't observe it.  (Neil Savage)

While I may strive for perfection in the rods I build, it is unrealistic to expect to reach that goal. However, I will accept extraordinary, which can be almost as elusive as perfect. That said, if the rod is pleasant to cast, isn't heavy or stiff as a tomato stake, and puts the fly where you want it to go, what else matters?  (Jon Holland)

What else matters depends on the maker.  If you're content to allow more than a few thousandths difference between your rod and the original design, that's up to you, and more power to you.  I'm not going to tell someone how to make the rod, though I will show them my techniques if they ask.  It all depends on how high you want to set the bar, and that's an individual thing.   If I  want my  rods to  be ±.0005" from the design taper, what concern is it of yours?  If that's the way that I want my rods to be, that's up to me, not you, or anybody else out there for that matter.

I'm not sure how in the hell "perfection" or the "perfect" rod got into this discussion, as it has no place in it.  The discussion was about accuracy, precision, resolution, and repeatability, based on the original design taper.  Anything else is fluff.  (Mark Wendt)

I need to purchase a 60 degree point and base to turn my dial indicator into a depth gauge.  The Starrett PT06632-6 Contact Point is recommended.   One could be ordered from Starrett for $4.50 plus $7.95 shipping which seems expensive.  Would the following point from Enco (here and here) and MSC work?  They don't seem to carry the version from Starrett.  Also, I was going to purchase the base in the second link.  However, Cattanach's book illustrates versions made from birch plywood as well as aluminum so I might make one.   (Ron Delesky)

Get the Starrett, you’ll be much, much better off….If you insist on something other. I’ve got a bunch of crap ones, some sold by reputable folks, that  I’ll give to you. BTW, get a Starrett 60 degree angle finder also. The cheap ones are not true at all.  (Ren Monllor)

Not sure on the tip but the base is what I ordered.  I actually had to glue a piece of wood to the bottom of it because it is not tall enough for the stem of the indicator to retract into the base if that makes sense.  It is not at all what I was hoping for.  It works fine with the wood attached to the bottom but I often wonder how accurate it is when setting the forms.  So far the measured strips have been pretty close and consistent to what I was shooting for so I haven’t felt the need to order a nice indicator with base from places like Golden Witch or anywhere else.  (Greg Reeves)

Indicators and bases are not universal. You have to match them. I suspect that you might have a 1" indicator with a 1/2" base, for example. If you have the opposite scenario, there are extension rods available to make the indicator reach longer.  (Larry Blan)

You will get better consistency if you use medium density fiber board (MDF) in  the place of the wood. It is much more dimensionally stable to changes in temperature and humidity.  (Doug Easton)

It looks to me as if the contact point in Enco's catalog is 90 degrees not 60.  I'd sure check it out before use if that's what you order.  Golden Witch is getting (or asking?) $16 plus shipping for their 60 degree point,  so the Starrett isn't a bad deal.  The one from Golden Witch is larger diameter though. (Neil Savage)

I did some more extensive searching online, and found out that MSC (link here) is a viable sources other than purchasing from Starrett directly for the PT06632-6 60 degree contact point.  MSC customer service indicated the 14 piece set described in the link is incorrect, and it ultimately is the 60 degree point.  (Ron Delesky)

I’ve got one of those quirky questions that will now keep me up nights until I find resolution.

My depth gage has a travel of 1.010” total while at rest (gage laying on its side, nothing touching the point).

If, when the point is flush with the bottom of the base (where both point and base rides on top of a flat surface), I zero the gage at its tenth .100” revolution (having the point travel its full one inch travel); Why would I get a reading that would be off?.

Think about it…It is zeroed when both tip and base are riding the surface of the forms. The point will drop the set amount into the groove and seat. The amount of travel should then be the depth of the v-groove.

Am I missing something???  (Ren Monllor)

Did you mistype your  original  travel?  You  say  total  travel  is 1.010" and you are zeroing at .100". That's .090" away from your zero point.

You need a constant to zero your gauge... one that has a predetermined and accurate measurement with the 60 degree slope. Your POINT will never be at zero unless it sticks every time you put it down... the miniscule amount of "roundness" on the tip will be enough to throw it off.  (Mike St. Clair)

The tip on the 60 deg point is not a perfect point. I believe the illustration in the Starrett catalog shows how much their point is rounded off. Anyway you can't zero a depth gauge with a pointed tip on a flat surface. You need a standard with a square & precise hole or some other way to zero off the sides of the point, not the tip. Some use the jaws of the good dial caliper.  (Frank Stetzer, Hexrod, Taper Archive, Rodmakers Archive)

I think I actually know the answer to this one.

The point of the 60 degree point is not the true point.  Usually you are off by a few thou, which is how much your point is worn down.  When you drop the point into the groove you are actually calculating the depth based on how wide the grooves are (sides of the 60 degree point).  That is why some people use a depth gauge "standard".

If you take a dial indicator and set it to .1122, then set the depth gauge on the that, that should give you a reading of depth of .100.

There are several ways to create a standard.

I know there is a power fibers article on it.  I am sure someone will chime in here with which PF it is in.  (Matt Fuller)

Power fibers Vol 15.  (Matt Fuller)

Actually the measurement needed to set your caliper legs to is 0.1155".  Set your caliper legs 0.1155" apart then drop your depth gage point into the gap with the base flat on the legs and your actual depth reading will be 0.100" or 0 on the dial.  Got this from Tony Spezio about 4 years ago.

Not "If you take a dial indicator and set it to .1122, then set the depth gauge on the that, that should give you a reading of depth of .100."  (Larry Swearingen)

Bill Waara used a drill gauge to check his depth gauge. The hole diameter times .866 should give you your proper depth reading.  (Ken Paterson)

I went through the same question when I started making rods. Yes, you are missing something. In using the indicator on a flat surface and you Zero the indicator, you are reading the indicator direct even if the point is flattened a bit. Zero will only be accurate if it is a perfect point. In reading the 60 degree angle, you are reading the angle of the point and not the actual end of the point. You can use a caliper and set it to .1155, put the point in the space between the jaws with the base on the flat of the jaws and Zero the indicator. (See my article in Power Fibers April 04) This will be zero or .1000 up a 60 degree angle. I make a Standard with a .1155 hole to set the indicator. Had the reamer specially ground to ream the hole. That is what I use to check my indicator for Zero. Doing it with the caliper is close enough.  (Tony Spezio)

I should also state the the rod is made of six strips, equilateral triangles tapering from one end to the other.  (Ren Monllor)

With all the talk on depth measurements etc. How often do you all change your points? (Jim Tefft)

I would think there's very little need to change a good quality point at all. It should be hardened considerably more than you planing forms. Also you should not slide the point down the groove between stations anyway.  (Larry Swearingen)

Drill or bore a hole into some steel stock or i have a friend who drilled a hole into the top of his planing form in the 1/8th to 3/16th range. it needs to be a clean hole but the diameter is not important. after you calibrate your depth gauge with you calipers drop the point of your depth gauge in the hole and record the reading that appears on your dial or led readout. you now have a sort-of calibration block. and a handy way to check the calibration of your depth gauge.   (Timothy Troester)

I am using the same one for 10 years The point has flattened some. New it was .001 flat it is now .003 flat but that makes no difference in this case, we are interested in the angle not the point.  (Tony Spezio)

Depth Gauge Point?

First thing I did with the one from GoldenWitch was stone off the point ~ who needs a point?   (Vince Brannick)

I am using the same point I started with 6 or 7 years ago. With a standard for set up I have not had any problem with dimensional control.  (Frank Paul)

Does anyone know if a digital depth gauge for setting planing forms is available and the source for said gauge?  (Phil Crangi)

Harbor Freight has been carrying them, reasonably priced, for a couple years now.  They are often on sale for about $19.  (Darrol Groth)

Digital depth gauge for $19? Are you sure you aren't thinking of digital calipers? I think $99 is the cheapest price that I've seen on a depth gage.  (Will Price)

Nope, he is right about the price Will. I got mine from HF and it works just fine. It isn't Starrett or Mitotoyo, but it works. I think they are regularly priced at $30-40.  (Scott Bearden)

Try here.  (Harry Boyd)

Do these read depth or does it just do a negative read out?  I'm not sure if I wrote that correctly or not to reflect what I meant.  (Greg Reeves)

Thank you for this information. I checked Harbor Freight on line and couldn't find what I was looking for. Can you please give me specifics?

I went by a local tool jobber here and they had a Chicago Brand gauge but the shaft was on the short side and I couldn't exchange their tip with the 60 degree one due to the fact that the threads were different on each gauge. The price was about $119.  (Phil Crangi)

Harry posted it earlier.   (Scott Bearden)

Wow. Thanks for that link. Guess I'll have to start checking the toyl sights a little more often.  (Will Price)

OK, since I have a predilection for asking "dumb" questions (that everyone else is wondering too but afraid to ask), How would one go about "zeroing out" a digital depth gauge for use with forms?  (Darrol Groth)

I would have thought just by using the "origin" button.  (Peter McKean)

The major reason the Thomas Edison was so successful was that he was not an engineer and he didn't know that something wouldn't work and went ahead and tried his ideas.

For me ignorance is bliss. I too don't know that it won't work. Thus, I figured that if the point from my current dial gauge will fit on the shaft of the digital gauge and I can mount the bronze base from the dial gauge on the digital gauge and then use the zeroing device that I got from Tony Spezio and set things up. I would then compare the results on the two gauges. If everything checks out then I will have been successful. If all else fails I will then invest in Jeff Wagner's digital depth gauge. I figured that with my summer free and a cash outlay of $35.00 I couldn't go too wrong.

I am sure that this explanation is as clear as mud, sorry.  (Phil Crangi)

Fine and well - but that's what I mean.  I think Tony's method "zeros" the gauge out, but it is actually set at .100 as it's constant.  How could one do that digitally?  (Darrol Groth)

On a digital you set the indicator to read  .100 if that can be done. I have not given it a thought. I still use the dial indicator. Scott give us a answer, I think you have one of my Standards and you use a digital indicator...  (Tony Spezio)

Using your standard with a dial indicator worked fine for me, but the digital indicator just has a zero button and I would have to constantly subtract in my head with every measurement. I just prefer the large digital display over a dial indicator.  I can glance at the number once and remember. For whatever reason I have to look at a dial indicator several times.

I never found a mathematically true way to zero it since the tip could be off by a little. I just gently placed mine on a precision surface ground slab of granite and zeroed it out that way. Since I always plane my strips over size once or twice before final planing, I just measure, measure, and measure again. As the saying goes, measure twice, cut once. I found my point and indicator combined are off by .001. It is good to know how much it is off, but I honestly rely on my calipers more than anything.  (Scott Bearden)

Thank you very much for this most helpful information. I am still not clear about the subtraction you mentioned. What is subtracted from what if you zero out the digital gauge? Forgive me for not understanding. Being mathematically challenged as I am and not having any engineering training at all this is all pretty confusing to me.  (Phil Crangi)

A friend and I had a similar problem with a digital caliper and a Waara block. I can't recall the exact way we dealt with it, but as I recall, we measured the standard and recorded how far off spec we were. We either opened or closed the caliper that amount and rezeroed it. (I should be able to reason it out, but every time I try, my head hurts and my teeth itch!) Thereafter it was dead on. The trouble with that is that while using the indicator, we hit "Zero" instead of "Off", and that required we redo the whole furschlugginer business again!

Not a lot of fun!

Maybe put tape over the "Zero" button?  (Art Port)

I learn something new all the time. Not having a digital indicator I was not aware that you could only zero it. In that case could it be zeroed at .100 on the standard then subtract or add to that. Actually that is what you are doing with the dial indicator using the .1155 Standard with the 60 degree point. Does the Digital indicator read + and -. I would have to have one to "play" with to see what has to be done. I know on the Digital Caliper I have that I don't use, I can hold the setting that is measured, close it and still read what it measured different I don't zero it. This caused me problems when I first got it so I put it away, and use my Dial caliper.  (Tony Spezio)

The gauge I have is the same one they sell at Harbor Freight. It only has On/Off and Zero buttons. Mine does allow for positive and negative numbers. Don't ask me why I fear having to subtract the .100. What I can say is that I failed to measure twice and cut once, once. I just found it much easier to zero the indicator on a flat granite plate and compensate for any inaccuracy by measuring the strips with calipers. I know not to rely on the tip point for accuracy.

You have always taught me to keep an open mind, keep things simple, don't accept anything as gospel, and use what works for me. That advice has served me well.  (Scott Bearden)

I don't think you can do that on most digital indicators.  As far as I know, on all the digital gauges I have, you can only "zeroize" them.  That's one of the reasons I've shied away from using a digital depth gauge.  (Mark Wendt)

I guess I will stay with my Dial Indicator. I have not even seen a Digital Indicator except in photos. There must be a way to use them without a lot of hassle, others are using them for rodmaking.  (Tony Spezio)

My guess is if they are using them, they're going through the mental gymnastics every time they set the forms.  It would be nice if the DG manufacturers would come up with a protocol that would allow us to programmatically zeroize the display against an offset, like I can do with the Digital Read Out on my milling machine.  Course, that'd probably make the DG much more expensive.  (Mark Wendt)

The type of digital indicator you want has a "preset" function.  I've picked up a couple on eBay for $30 or less, mounted them on a base & sold them with a setting standard.  Here's one on eBay now:  Item number: 260422697994.  This is a Mitutoyo, I use a Sylvac but several other manufacturers make digital indicators with a preset function.

A way to accurately set a digital indicator without a preset is to make an adjustable setting standard.  This can be as simple as a set screw that's been flattened on the end and screwed in a flat hunk of metal from the bottom.  Adjust the setscrew to take account for the 2, 3 or 4 thou truncation of the sixty degree point.  If you use a setscrew with a nylok insert the screw won't move once you've set it.  Then you can zero the gauge on the setscrew.  Zeroing on the point will wear it off, but you can readjust the standard.  You'll know if you check it to Tony's method using calipers every once in a while.  (Ron Larsen)

How does the "preset" or "origin" function work on these DG's?  I looked through some of Mitutoyo's literature, which mentions the function but doesn't go into any detail as to how it actually works.  (Mark Wendt)

On my Sylvac there's a setup menu where you enter a number and either a plus or minus.  For example, I bored a sixty degree hole in a flat block of steel to use as a standard.  Using several different methods I found the hole was .234 deep.  Using the setup menu I entered  -.234 for the preset.  Now when I turn the indicator on I check the standard.  If the indicator doesn't read -.234 (it'll move around a little) I hit the preset button with the indicator setting on the standard.  The Mitutoyos are basically the same.  (Ron Larsen)

Ah, okay, that doesn't sound too difficult.  Mitutoyo is one of the high end indicator manufacturers, so I would expect they'd have come up with something like that to make the DG work in a variety of ways.  I'll have to take a peek at the Starrett's and see if they have a similar function.  (Mark Wendt)

This is what I thought can be done with the .1155 standard I make. If the point is set in the hole, and the indicator zeroed, would that not be the same thing. Would it keep the .1155 internal reading. The Standard does not read the actual point, it reads the 60 Degree angle .100 up the slope.

I am totally confused at this point. Scott will bring his Digital indicator up next week and I will get to do some research on this. I am sticking with my Dial Indicator.  (Tony Spezio)

Thanks to a radical suggestion to actually look at my HF digital indicator, alas, I find that it has no +,- adjustment - only zero.  I don't know if the more expensive guages have this adjustment feature.  Still, I suppose one could calibrate the same as a dial indicator to .1155 and just treat .000 as .100 as we do with the dial indicator.  I just wondered if it could be calibrated at .100.

Will full retirement lead to more useless mental gymnastics such as this?  (Darrol Groth)

Will find out when Scott brings his over next week. Will see what it will do. If it will zero with the point in the .1155 hole, then I can figure how to use it. I just don't have a problem with my Dial Indicator except when I dropped it on the concrete floor. Well I had to spend another 10.00 ( 9.97 on sale HF) to replace it. LOL My Starrett indicator stays in the case.  (Tony Spezio)

OK, just returned from HF with my 29 dollar digital dial indicator.  Spent half an hour calibrating it.  Here's what I came up with:

a. replace cheap ball point with Starrett 60* point.

b. mount indicator in the measuring tool block

c. placed the indicator/block gauge in my 0.200" V-block gauge standard (use whatever standard you have) then set the indicator to ZERO

d. placed the newly zeroed indicator over a hole in my forms which I turned on edge.  I backed the bolt out till the indicator read -.0200" then ZERO'ed it again.

e. put the indicator back in the V-block standard and it read .200" just like it should.

So what I did was basically:

1. zero the gauge to the standard

2. find a way to accurately run the indicator to the negative of the standard

3. now it should read accurately in your standard

NOW the question is 'will this thing remember the setting if I turn it off?'  My Mitutoyo Absolute digital indicator does remember this.

Anyone whose digital indicator is not set up yet want to set it to read something repeatable, turn it off, then see if it remembers the setting.  If not, I guess I'll find out later tonight.  (Rick Crenshaw)

OK, at least for the short term (5 minutes) it does indeed recall the last zeroed setting.  So it looks like my digital indicator is set up... at least until the battery dies, the tip get too worn, or I screw with it. (Rick Crenshaw)

The HF dial calipers hold it till you screw with them - so it ought to as well. Just be careful what button you push when you turn it OFF!  (Art Port)

Too darn complicated for me, make sure the point is tight, set it on top of the form so the point is NOT in the groove, set it to 0 and go to setting. Oops, I guess I just promised not to do that, never mind.  (John Channer)

That works if you are totally sure that the point is really the "true" point...   (Mark Wendt)

BTW, since you pointed that out, I just flashed on something. If you find that the delta between POINT and reality-tip is a fixed amount, say, .004, why not write that amount on the base and get a known thickness shim, and let the point sit on THAT, then zero the indicator. Flaws in the thinking??? I already thought of ONE: the shim would have to be smaller than the hole in the base, or the base would sit on it and screw up the method.  (Art Port)

Heh, I posted the method I use yesterday, but it didn't seem to make it. That is just what I do, works like a charm. I do like Ron's adjustable standard, though. I have a rather large gage block I use when I'm looking for something flat, and it just happens to have a hole conveniently located in the center.  (Larry Blan)

My strips measure what the form is set at, so I guess I don't care if the point is true or not. At least my indicator and my caliper seem to agree.  (John Channer)

Or else your indicator and calipers are conveniently off by the same amount...  (Mark Wendt)

How's this for low-tech?

I  just trust my indicator, zero it on the flat, set the forms, plane the first strip, and take perhaps 15 extra minutes to measure the 5" stations while getting down to the forms, and adjust the form settings as, if, and where it is needed.

Then the next eleven or five strips are easy.

Boy, what a dumb way to do it!  (Peter McKean)

Pretty low tech indeed.  That technique assumes your strip measuring tool is accurate.  Had it calibrated lately against a standard?  For me, I'd much rather have two precision measuring instruments telling me the same thing.  (Mark Wendt)

Yep, Mark, if I were running the metrology Department at the Rolex Watch Co, I am sure I would agree!

In fact I do check the calipers, though I must confess not very often.  I use a Mitutoyo digital caliper, and a Moore & Wright micrometer which claims to read a kazillion decimal places, and I do check one against the other.

Occasionally.

I guess, if I were to use a CNC mill to finish my strips, I might feel a greater obligation to  strive for exacting levels of precision.  But in fact I hand plane them with a couple of  L-N block planes on a set of forms that a machinist mate made me.  This bloke has a factory which works to a pretty high level of precision - makes gear box parts and stub axles for Caterpillar - but heck, the forms are made of BMS, and they live in my workshop, and I tidy them up every now and then with a draw file, so how precise can they be?

And one must also bear in mind that I am working with bamboo.  I am a veterinarian, not an engineer, and the abiding wonder of my life is that I manage to produce rods which mike out as close to target  dimensions as they do.

So while I do buy good tools, and take good care of what I shell out for, I am not about to lose much sleep over whether or not my dial depth indicator may be out by a thousandth or so.  That is why I check its output against another reasonably accurate tool, and sometimes in turn check that against one which is potentially more accurate still.

And now that this question has come up, I may just trundle the whole box and dice out to my Caterpillar friend and get him to check the lot in his metrology section. And no doubt be shocked and amazed at what he tells me, dammit!

But unless I get cranky and drive the car over the calipers, their accuracy is still likely to be way better than my ability to test it with precision work.

I have deep and abiding admiration for engineers and toolmakers and machinists and anyone else who can work to those mind-boggling tolerances, but I just ain't one of them!  If I can refine my technique to the point where I don't deform the apex of the strip significantly when measuring it I will feel reasonably happy.  This is probably the real reason I crosscheck with the micrometer, as I feel the pressure control will even this one out a bit.

In the final analysis, I live in an area where I am only 20 to 30 minutes from excellent dry fly fishing for wild brown trout,  and I produce split bamboo rods for myself and my customers to fish with, and they seem to be very happy with the result.  I do all I reasonably can to ensure that I produce a quality product, and one that is predictable performance, but I do it by the "measure and check" method that I outlined yesterday, and a thousandth of an inch slop in a strip doesn't cause me to lie awake at night.

I have other things, like suture lines that threaten to break down, I/V's that block up and patients with bloody undiagnosable illnesses to do that!

:-)   (Peter McKean)

Didn't mean to impugn on your rod making skills Peter.  All I was saying was that if I'm going to check one measuring device against another, I'd like to be reasonably sure that one of them at least is accurate.  The forms themselves mean little in this discussion, except for the accuracy at which they are set.  To set those forms accurately and precisely, one's measuring tools should be both reasonably accurate, precise, and repeatable.  Otherwise, what's the sense of using them?  We might as well go back to the setting the strip measurements using 64ths again.

Yes, we are working with bamboo.  But the measuring tools we use are usually made of some kind of metal.  They can lose their accuracy sometimes because of the littlest things.  If you don't care about accuracy, it's no big deal, it's your own outlook.  I like to keep my measuring tools as accurate and repeatable as I can, that's my outlook.  I use my measuring tools for other uses besides measuring a bamboo strip, such as measuring diameters (inside and outside), depths, lengths, widths, bores and other dimensional things working with metal, plastic, and other materials.  Some have no need of tight tolerances, some have need of extremely tight tolerances.  Either way, I need to know that my measuring tools are accurately, precisely, and repeatedly giving me the correct measurements.

It's a pretty simple operation to ensure the accuracy of your measuring instruments in your shop.  Gauge blocks, gauge balls, precision ground pins - any of those are accurate enough to  get you to within a half thousandth, and are inexpensive enough to have a few on hand.  It only takes a moment or two to check your measuring device against a standard like that, and it's nice to know if your measuring device falls within your standards.

That CNC machine will use the same type of measuring devices to determine the accuracy of it's operation as one would use with the hand planing operation.  The same tools and such that I use now when I hand place strips.  I'll just be measuring those strips in 1" increments, rather than the 5" increments I do with a hand planed strip.

To each his own though.  If a person wants to work with measuring devices he or she has no idea as to their accuracy, it's completely up to that person.  (Mark Wendt)

I had this quote hanging on my office wall for years:

When you can measure what you are speaking about, and express it in numbers, you know something about it; but when you  cannot measure it, when you cannot express it in numbers, your knowledge of it is of a meager and unsatisfactory kind; it may be the beginning of knowledge, but you have scarcely, in your thoughts, advanced it to the stage of science.

Sir William Thompson, Lord Kelvin (1824-1907)  (Ron Larsen)

However, Kelvin was very famously wrong in matter like this. There was a controversy over the estimated age of the earth in he late 19th century. Based on the measured heat flux from the core of the earth, Kelvin calculated at most a few million years. The geologists, based on more diffuse but widespread evidence (that Kelvin denigrated as in this quote), said at least several hundred million years. What he didn't know about was radioactivity, which is the main source of heat flux from the earth, and isn't going to run down in any few million years. So rather than regarding the geologists' number as a clue, he dogmatically missed out on one the fundamental topics of physics in the 20th century.  (Mike McGuire)

No, Mark, I realize you are not impugning my ability; I follow your comments with interest, and with the CNC thing, with a lot of awe.  You have, though, made me think a bit about calibration.  I will start with a visit to my friend's metrology section to see what the status quo is, and will see from there.

While I may be of a mindset that does not prioritize extreme accuracy, I have to admit that it can't hurt!  (Peter McKean)

Absolutely!  The things we can be accurate with, we should, the things we can't be accurate with, we try our best.

The CNC thing is not all that difficult once you get a design down on paper (or computer data bits as it were).  The nice thing about designing and drawing it on a Cad program on a computer is that it's a whole lot easier to change things when you realize as you start assembling parts that what you thought would work, via the drawing, doesn't quite measure up to what happens with the nuts and bolts.  I've done more reading about this and that over the last few years while designing and building this monster.  Thankfully, there are a ton of resources out there on the Internet to help form an opinion on which direction you wish to go.  As with anything else on the World Wide Web, you need to consider more than one source.  I've had help from Hal Bacon (where the back of the cocktail napkin design originally began - he gave a presentation on the Leonard and Payne saw bevelers a few years back at the Michigan Grayrock Gathering), Bob Nunley - who allowed me to take a bunch of pictures of his saw beveler and ask a ton of questions, and a great many other folks in the homebrew CNC world on the internet.

Now, it's just a matter of money and time.  Money to buy the pieces I need to assemble the thing, and the time to do it.  The gantry and cutting head is almost complete.  I still need to finish up the final engineering and build drawings for the base so I can fit and finagle all the little bits and pieces on the thing.  The computer with the CNC software is up and running, the controller box has already been built and wired, and the stepper motors are all wired up.  (Mark Wendt)

Only problem is, what happens if your base has shifted minutely betwixt the last time you used it and this time?  Just being knocked around the bench could affect that.  You should always check it against the standard before each use (ie; each time you turn it on)  I do it every time I need to reset my forms, or need to check the forms to ensure the depths are correct.  (Mark Wendt)

That worry is true of any indicator set up.  I do check my indicator against the standard regularly.  Here's a few more tips for maintaining indicator calibration.  Sometimes using those tiny little set screws in the side of your solid steel indicator block helps to stabilize the indicator's position in the gauge.  Another thing, I don't throw my gauge around the shop, but rather place it gently on an unused corner of the bench over a 3/4" diameter bench dog hole.

More importantly, I'm not typically drinking heavily while making rods. 

A good rodmaker should try one or all of those strategies.  (Rick Crenshaw)

After acquiring a preowned Mitutoyo digital depth gage I could not figure how to preset it accurately to anything other than 0.0000. Unlike the purely mechanical regular dial indicator there was no way to bias the readout that I could figure since  no user's manual came with the digital depth gage.

Fortunately I got lucky and discovered that the shortest extension for the indicator stem that came with the digital depth gage is, as exactly as I can determine, the same length as an unworn Starrett 60 degree contact point.

To zero the digital depth gage all I do is remove the 60 degree point, install the short indicator extension (without a contact point), set it on a flat surface and hit the zero button. I check it after reinstalling the 60 degree point, sometimes with my caliper set to 0.1155 but most usually with the #32 drill hole on a number drill gage, to see that the indicator reads 0.1000, and it is always within 0.0005 of that. I also have an off-brand depth gage and an off-off brand dial indicator with a collection of contact points and extensions. Each has an indicator shaft extension sort of like  the one  that came with the Mitutoyo. One is exactly the length of an unworn Starrett 60 degree point, like the one that came with the Mitutoyo, and the other is off a few thousandths.

So check the miscellaneous parts that came with your digital depth gage because you may have a zero calibration gage there and not know it.  (Joe Hudock)

I am a beginner, and need clarification concerning how to properly read the dial indicator. My indicator is the same one that Bellinger sells. My understanding is that it needs to be read backwards. Can someone explain how this is done and why It is done this way. Do I need to utilize the smaller number, and then add how many .100" based upon the smaller dial? For example, if the big dial reads large number 30/70 small number with the small dial between 0 and .100 then what would the depth ultimately be?  (Ron Delesky)

A good way to avoid that hassle is to get a handmilll... "0" means "0"... not .399" Just a thought... :)  (Mike St. Clair)

Address your question Joe is much easier to show you than to put in text.  Have a look at my articles, or any of the rod making books.  The reason for using a dial indicator is simple economics.  A depth gauge is easier to use but costs several times as much.

Work the indicator a little back and forth by hand and you will see that as the plunger moves away from the body the dial turns in one direction.  As the plunger moves towards the body the dial works in the other direction.  Place the indicator on a flat surface like your forms.  That should be close to "zero" (prob'ly about -.003 - .008)  Each revolution outwards is .100", so add that much to the smaller numbers.

Confused yet?  (Harry Boyd)

Good job Harry, I thought about taking a stab at it and it gave me a head ache!

Joe, like Harry said a picture is worth a thousand words, although I don't think Harry said that! Maybe in other words - but - OW - there's that headache again.  (Joe Arguello)

If you can't get a dial indicator depth gage then get one of the dial indicators that have two scales on the dial.  One that has numbers that get smaller as the probe goes probe and one that reads larger as the probe goes out. You want to use the scale that reads larger as the probe goes out. You don't want to have to screw around with math while you are setting your planing forms.

Just my opinion  (Larry Swearingen)

My dial indicator is a cheap Chinese one from Enco.  I took off the glass and pasted on new numbers so it reads depth.  Put "10" to cover up the "90", "20" over "80" etc. Took about 15 minutes and saves that time back in  few rods.  (Frank Stetzer, Hexrod, Taper Archive, Rodmakers Archive)

The cheap Chinese one I got from HF last fall has both sets of numbers - 90/10, 80/20, 70/30...  (Larry Lohkamp)

Does anyone here know how to adjust a Mitutoyo Dial Indicator when it is on a standard? (either the .1155 one or my Catalano bar)  I do not want to zero it on a flat surface and blunt the 60 degree point. Thank you for considering this.  (Mark Steffens)

You CAN'T zero it on a flat surface - it's already MADE rounded by a thou or so. The actual point is NOT the virtual point that the sides of the cone "theoretically" meet at.

What you need to do  is "zero" it on the same sides (of the cone) that you'll be measuring your form settings with. You're actually using what your geometry teacher taught you about the 30-60-90 triangle.  (Art Port)

You made reference to a "Catalano bar" in your post.  Is that the standard that was provided by Wayne Catalano who used to make planing forms?  If it is, you set the point in the standard where it has the small indentation and you set your dial at .100.  It's been a while so if I am wrong about the measurement you might ask one of our resident machinists.   (Hal Manas)

I've never played with one, but I think you are asking how to set a digital gage to a number that is not zero? From what I have read, you can't. Could be wrong, but I'll try to help assuming that is the case.

Either slide the indicator up and down in the base to reach the number your calibrating to, or zero and do a bit of arithmetic as you set your forms.  (Conor McKenna)

Some time ago I copied the information below for depth indicator calibration to a "sticky note."  Don't remember who is the author.  I have a question:  what is the reason for having to calibrate the depth indicator in this fashion?

Text from the Stickie:

Here's the solution. Zero out your dial caliper and then set the opening between the jaws to .100. Put the dial indicator between the jaws,  and turn the dial until it reads  .866. Lock the dial in place, and you've calibrated the depth gage. You'll note the wooden base on my depth gauge. The 60-degree tip is a bit wide, and catches on the metal base that came with the indicator. A lot of rodmakers use wooden bases, and until I get around to buying a new tip, I will, too.

But depth gauges are like fishermen. They aren't always truthful. Set the forms .003 inch wider than called for, and plane a spare strip of bamboo. Check the size with your calipers, and adjust the forms until your sample and your calipers tell you you've got it right.  (Wayne Thompson)

The reason is that the point gets flattened and you will be setting the indicator at the difference of the flat on the point and the flat surface. If the point is .004 flattened, zero on the scale will be a + .004. In measuring up the 60 degree angle will give you an accurate measurement at that point. I use .1155 on the caliper and set the indicator to Zero. This is really .1000 up a 60 degree angle. The angle is what is used to measure the form opening.  (Tony Spezio)

I received a Bellinger planing form/depth gauge as a Christmas gift.  My understanding as a beginner is that the depth gauge must be read backwards thus the smaller numbers under the larger main numbers due to not being a reverse reading dial indicator.  So if the larger dial is on 70/30 in conjunction with the smaller dial is between .100" and .200" then the depth would be .100" + .030" or .130".  Also, I would need to zero the depth gauge before using via opening a caliper to .100", and the gauge should read between .086 and .087.  Would this ultimately be correct?  (Ron Delesky)

Honestly Ron, I ignore the smaller dial as I don't think it correlates with actual depth when you're using the indicator the way we do -  bass-ackwards as it is. Why don't you just acquire a feel for the thing by setting it with the resetting standard so you know it's actually accurate, then place it into the thin end of the tip groove, and then you'll know that whatever it reads is between 0 and .050 or so, not over .100, which would be waaay too big. THEN look at that little dial and see what it looks like.

You DO know about using the standard, correct? If not, fire one back and I'll try to explain the need and method for it.  (Art Port)

That is correct. On Calibrating the indicator. Why not set the caliper to .1155 and set the indicator to zero instead of .100 and 86. Setting it at Zero is actually .100 depth reading.

Then use the small numbers to set the forms. If you have Power Fibers Issue # 15, Check out my article on this.  (Tony Spezio)

To make this clear, the small numbers are on the face of the indicator and not the small dial. I go along with Art, check the small end to the large end of the groove, this will give you a better idea as to what the indicator is doing and the direction the needle is traveling..

Lift the point off the form at each station as not to damage the point.  (Tony Spezio)

I've been using one of the bases from Enco I think but the problem with it is that it isn't  deep enough to hold the dial indicator.  I had to epoxy on a piece of hardwood to extend the depth of the gauge.  This worked for a while and I was o.k. with it but this weekend the base separated from the wood.  I'd rather not repeat the same thing and I am trying to figure out an alternative.  I would also not like to use wood anymore.   I have a drill press and a tap and die set so I would like to fashion one out of metal.  Does anyone know where I could get a small piece of round brass or other material suited for this?  I was also thinking of going to the hardware store and picking up a large carriage or shoulder bolt and saw off the threads, drill it, drill a hole for a set screw in the shoulder, and use this.  What do you think?  (Greg Reeves)

Tony Spezio had an article in Power Fibers a while back on making a depth gage base. I used it as inspiration for my own creation. Before that I just used a chunk of maple cutoff from my homemade planing forms. As with Tony I used aluminum. Bought some chunks off ebay. Its cheaper than brass and a lot easier to cut than steel, although all I had to do was some drilling and tapping.

A large carriage bolt would be a chore to cut, much less cutting it straight. Unless you have a lot more tools than I do. Not to mention a better hardware store that would have a carriage bolt large enough in diameter for a depth gage base.  (Joe Hudock)

I found the Power Fibers article and already found a source for the Aluminum.  Thanks for the help. (Greg Reeves)

Check this.  A one-foot section is $24.08, plus shipping, but maybe Joe would buy your "cut-offs."  :-)

I found this by googling "brass round stock."  (Steve Yasgur)

I made mine from a 2" long piece of 1-1/2" diameter steel shafting.  You can often find short pieces (cutoffs) in the scrap bins of local machine shops or a steel supply yard often sells them.  Of course brass or aluminum would work fine also.   If you can find a suitable piece then all you need to do is drill through the center for the spindle diameter and then a cross hole threaded for a set screw.  You should be able to do this on a drill press just fine.

Worst case you can order short pieces of metal by the inch from a number of on line metal suppliers.  Metal express and on-line metals come to mind.  (Rick Hodges)

I'd try to do the drilling either on a lathe after facing the bottom of the base or on a milling machine after machining the base so that the hole for the indicator is perpendicular to the bottom of the base.  Otherwise, you may induce a cant to the indicator when it's mounted in the base unless you've got a pretty decent drill press that doesn't allow the drill to wander much.  If the indicator isn't perpendicular to the bottom of the base, your depth measurements will be off.  Drill presses tend to have a lot of slop in the quill.  (Mark Wendt)

After a similar experience I bought a brass indicator base from  Dave LeClair. Price was right, product is great, and his service is excellent.  (Jim Healy)

There was a discussion about a standard for setting your depth gauge using a flat steel with a 1/8” hole.

Can someone remind me what the gauge should read sitting in the hole? (Scott Grady)

It should read 0.1083. In general, it is the diameter of the hole times the sine of 60 degrees--0.86603. The preferred way to make the hole is to bore it a little undersize, say 7/64 and then take it to diameter with a 0.125 reamer. (Mike McGuire)

You can also use a drill gauge.   (Ken Paterson)

But more useful is to put a hole right in the surface of your planing form so you don't have to recall where you put the gauge.  Actually several holes are better, for a cross check in case one of them goes off. (Mike McGuire)

A number drill gauge is really convenient. The number 32 drill has a 0.116 hole size so the depth gage can be set for a depth of 0.1 inches when the 60 degree point is set in it. The other holes can also be used. You just need to do the math to convert from hole diameter to gage depth setting.

I have found the holes on front side of the gauge have a slight chamfer to facilitate checking drill sizes but that the back side of the gauge have nice sharp corners so work better for checking the depth gauge calibration. (Joe Hudock)

And, once again please, what is the method using your calipers as a depth gauge? (Reed Guice)

There are two ways. One: set your caliper to 100 and lock it. Your depth indicator should read between .086 and .087. Two: set calipers to .1155, set indicator in caliper jaws and it should read 100, if not adjust. (Larry Myhre)

Right!  .1155. (Reed Guice)

I have made several standards for students. I start out with 1/8" thick brass flat stock, 1" wide by 2.5" long. I drill a .113" hole in the center. With a small tapered hand reamer, I delicately open up the hole to .1155". I check my progress frequently with my depth guage that has already been calibrated. When the guage reads 0 after one revolution, .100", I stop. By using the hand reamer, I eliminate the cost of having an expensive chucking reamer made to an accurate .1155" diameter. (Lou Barbaro)

Has anyone tried cutting their own groove in the base of their depth gauge, for measuring strip height in the planing forms?

What would be a good way to accomplish this? (Bill Walters)

I grooved several bases, but for a different reason.

I use it to check plane blade skew and distance out from base.  Use the round end tip that comes with the indicator.

You can use a file since it does not have to be perfect.  I used my small milling machine. (Scott Grady)

I like the easy way.  Instead of cutting into the base, epoxy 2 brass standards onto the base, one on each side, to raise the base. (John ??)

I used a standard magnetic base.  I modified the rods and stuff that hold the dial indicator and incorporated a spring adjuster for a sort of ‘vernier’ control.  The objective of these mods was to get rid of as much of the rods and connectors that are normally used with the base as I possibly could.

The feet on the two sides of the magnetic base span the groove in the planing form and provide plenty of room for the strip to pass through.  When I used this rig I attached a flat tip to the indicator, but your choice is your preference.  You can make this sort of set up as fancy or as simple as you like. (Bryan Coles)