I must say that, having tried several methods of producing straight sections, I am quite convinced that there is none so simple, nor so effective, as simply binding carefully and then taking a bit of time to tweak and straighten prior to hanging to dry.
There are several charms attendant on epoxies as a class, one of which is their very long working time. There is just no hurry, and it is an easy thing to take the time and get the section right. If the string subsequently comes off to reveal some minor bends that were not visible under the string, then good old epoxy will allow easy heat straightening with no appreciable price to pay for this.
It is worth noting that the time required, and the amount of heating necessary to achieve plasticity is very, very small, (seconds on tip sections) and I suspect that most of the horror stories about heat-straightening destroying sections may be stories here the process involved much, much more heat than is really necessary.
But, and this point is also worth making. I think that these days I probably spend more time on initial strip preparation than I do on final planing. I like to start the establishment of the initial 60 degree angles using strips which are already as physically straight as I can make them, with all four facets straight, square and true, and the nodal humps pretty well gone.
"As ye sow, so shall ye reap" somebody once commented. (Peter McKean)
I believe you're essentially correct about the ease of straightening Epon-glued strips. This is because the "curing" regimen in one's oven (say, three hours at 180 degrees the day after the glue has set up) does not entirely cure the glue. It's damn tough at that point, but there remains a period of perhaps at least another day or two when the strips can easily be straightened. Within a week, however, the glue will have reached its full strength and straightening at that point is nearly impossible, requiring more heat than the cane can really bear.
I wonder what others have found in this regard. (Bill Harms)
Well, galvanized by Bill's remark about the permanent setting of the Epon in a week or so, I just had a go at those two tips with a steam iron. One is a straight as it ever will be, and quite good. The other will have a slight sweep forever and various attempts to get it straight and the elapse of time has set that Epon hard I am sure.
Thanks gentlemen all for your useful remarks throughout.
I am also noting carefully Peter's remarks about strip preparation to essentially remove or minimize the need for straightening. (Sean McSharry)
I use Epon too, and have found that even after I heat cure the blanks, with judicious application of heat you can still straighten rather easily, whether it's right after the heat cure, or even a week later. (Mark Wendt)
I find it amazing that many of us follow procedures that are very similar, but our results are often nothing alike. Several years ago we pursued a thread on heat treating that comes to mind. Some said 7 minutes at 375 was just right. Some said that same recipe did little or nothing. Still others said the same time and temperature produced charcoal.
I have two sets of 3/2 rod blanks glued with Epon and heat set more than a year ago in the shop. They have the normal crooks and kinks. I'd almost bet you that working just like normal I can have both blanks straight as arrows in an hour. Yet I hear my friend Bill say that he finds straightening Epon glued blanks nearly impossible after a week or so. It intrigues me. Not long ago someone else on the list implied that Epon glued blanks were especially tough to straighten once truly set.
I have always believed that in straightening one softens the bamboo rather than the glue. Am I wrong about that? (Harry Boyd)
I suspect that with Epon, both the glue and the bamboo soften, although to differing degrees. I agree that sections can be straightened with heat no matter how much time has passed. (Steve Weiss)
I was the guy who had a bad experience with straightening epoxy-bonded sections after heat curing. I agree with Bill that once heat-cured, epoxy bonded rods can't be straightened easily if at all. However, I don't agree with Bill when he says 3 hours at 180F doesn't fully cure. My information from the manufacturer suggest that in fact this regimen does fully cure the epoxy.
As far as the straightening process goes, my IMPRESSION is that heating to straighten a blank softens the glue enough so that the splines can slip a microscopic amount. That is, the glue is plastic. I haven't done a careful experiment to back this up but I think that the temperature necessary to cause the DRY bamboo to become plastic would be too high for most glues. (Al Baldauski)
I hope you'll give the crooked sections you mentioned a try. I'd really like to hear what the results are. Despite the risk of blowing holes through my theory, I hope it works great for you.
But, here's "wrinkle" concerning Epon that I've often wondered about. The factory spec. sheet explains that a range of mixes (resin-to-hardener) will produce widely varying physical properties. The recommended mix is 1:1, but one can safely go as far as 2:1 (resin-to-hardener). The primary differences from one to another are the strength of the cured bond and the time needed for full cure -- the less hardener, the longer the cure-time and the greater the bond-strength. (I always use a mix of 1.5-to-1, thinned a tad with lacquer thinner) But what I'm wondering is if there are also changes in how the various mixes react to heat.
Because we're working with a laminate and several, radial glue lines, I always thought the glue would need to become somewhat pliable right along with the cane -- thus allowing the straightening to become permanent, once cooled. I think it's a mistake to assume, with a laminate in particular, that whatever the glue is, it will be happy to just sort of "go with the flow" when the rod section is heat-straightened. On the contrary, I think if the glue can become pliable while heating the cane, the straightening will work, but if the glue has more resilient physical properties and cannot soften enough to accommodate some stretching, permanent straightening won't happen.
There are, of course, forces of compression and tension in the straightening process which heated cane can easily accommodate, but if the glue cannot not do likewise, apparently the new shape of the cane can't overcome the resisting glue lines that want to go back to "business as usual." (That said, it may be that a butt section, with it's greater mass, could be a different case than a tip section.)
All glue becomes plastic with heat, until a certain point is reached when the glue begins to fail and break down. But the big question is: what ARE those temps? I think we've all found that various glues react quite differently. When straightening a section, there's a sort of "window of opportunity" as far as heat is concerned, where both cane and glue become softened enough to allow the bending. One hopes the glue is such that it merely becomes pliable, stretches along with the bend, and upon cooling, returns to its original strength.
Most glues will do this, although some (like Elmers and Titebond) have a narrower window and risk loosing their bond rather early in the heating process. Unfortunately, others, like fully cured Epon do not become pliable until the cane is all but scorched -- maybe not even then, I'm not sure. I've had excellent results, however, straightening rod sections even on the second day after the oven "curing" regimen. But after a week or so -- Whooo-ee, you got trouble. (Bill Harms)
Methinks I'd try less heat for a longer time if I was having trouble straightening a rod. (Neil Savage)
I will give those crooked sections a try tonight. As I mentioned before, I suspect I can bend them into pretzel shapes without harming the bond or scorching the strips. One thing that makes me think I can is that the only two rods I made which have "taken sets" were no trouble at all to return to straight. As far as I know, they are still fairly straight. Of course, this is only anecdotal evidence.
Mentioning the different resin catalyst mixtures started me thinking. I actually don't use the 828 resin and 3140 hardener that many others do. Martin Darrell Odom and I talked at length with the technical gurus at Miller-Stephenson and Shell. They strongly suggested using 826 resin because it is thinner (don't remember if "thinner" is more or less viscous). They also suggested a combination of 3140 and 3126 hardeners. I currently use the recommended combo of resins, mixed at 79/21 by weight. I premixed a pint of the hardeners, and use a 50/50 mixture of 826 resin and the combined hardeners, by volume. Perhaps my use of the different resin and hardener accounts for my ability to straighten at will, although when the tech guys were asked about the differences in strengths and other properties between the mixture I use and the semi-standard 828/3140 mixture, they acted as though the differences were very slight. Why change from the established mixture? Well, to get a thinner mixture and ostensibly smaller glue voids, and to get a higher heat deflection temperature (whatever that means). The different resin/catalyst mixes also allow me to safely mix small quantities of an ounce or less by volume rather than dragging out the gram scale each time I glue something.
There is definitely a difference in the way the 2/1, 1.5/1, and 1/1 mixtures react to heat. You may be on to something here.
Another interesting point of debate concerns the practice of heat-setting at all. The tech guys told me that cured is cured, no matter how we get there. You can cure at 350 degrees for 7 minutes, or 180 degrees for three hours, or a week or two at room temperature. According to the tech folks, there is no difference. Like you, I cure at 185 degrees for 3-4 hours. Why? Well, that's how I was taught to do it. Reminds me of an old story about a wife, a roasting pan, and a ham. You know the one.
I remember hearing or reading somewhere that there is a window between 140 degrees F and 190 degrees F in which we can work with completely cured glue... but I don't remember exactly what those temp's represent. A little common sense tells me that those temperatures are very warm to the touch, but not quite hot enough to scald skin. So when I get the cane so warm that I can just barely hold it, I'm in the right temperature range.
One neat thing about Epon is that even completely cured Epon remains quite flexible. Next time you glue some strips, pour the excess glue on a pane of glass or plastic. Let it completely cure. Maybe even heat set it. Using a razor blade you can scrape the whole mess off the glass. It will still be quite flexible. You can stretch it, bend it, even try to crease it. It cuts like butter with a sharp knife. In fact, it seems quite rubbery.
Someone mentioned humidity - temperature - skill variants. Skill might make some difference, but there is no question that both Bill and Harry have built enough rods to be at least proficient at it. Degrees Fahrenheit is degrees Fahrenheit, whether in Louisiana or Pennsylvania. As I understand it, humidity should have absolutely no effect. Epoxy will actually cure underwater if the temperatures are suitable.
I'm afraid the mystery remains. Why do rod makers A and B have different results with quite similar, almost identical, practices? Perhaps that's part of what keeps this craft interesting. Tell you what, my friend, if I can straighten those section in the shop tonight, I'll set up a straightening service as part of Boyd Rod Company, Inc. Then I can straighten all your tough kinks and bends for you -- for a small fee, of course <g>. (Harry Boyd)
Resolution Products now produces the Epon/Epikure line of epoxies. According to their literature this is what happens when you mix at different ratios and cure at different temperatures:
A B C D
Epon 828 100 pts 100pts 100pts 100pts
These are parts by weight (100/45 equals 2:1
Epikure 3140 45 pts 90 pts 45 pts 90 pts
Ultimate flexural strength
14000 12000 12500 11000
Ultimate tensile strength
8500 7300 7400 7500
Heat Deflection Temp (Degree C)
97 72 66 64
Izod Impact .51 .88 .63 1.18
Sample A & B were cured 16 hours at 25 degrees C then 3 hours at 100 degrees C
Sample C& D were cured for two weeks at Room Temp.
1. 2:1 by volume mixes give greater strength that 1:1 by volume
2. Heat-curing gives greater strength than Room temp curing
3. Heat Deflection temperature is higher on heat-cured mixes which means it takes a higher temperature to soften the epoxy and make it plastic. Some epoxies have a narrow softening window. Get too hot and they breakdown quickly. The significant increase in HDT for the 2:1 mix, heat-cured, suggests why Bill Harms (at 1.5:1) and others (at 1:1) find it easier to straighten after room temp curing or even heat-curing.
4. Izod Impact is a testing technique to evaluate brittleness of a material. The 1:1 mixes have a higher impact strength. They are therefore more flexible, less brittle. That goes hand in hand with the other characteristics. And, typically, when you mix epoxies at ratios other than ideal, i.e. with a surplus of either resin or hardener, you get a softer, more flexible material.
Hope this sheds some light. (Al Baldauski)
Thanks much for that information. It's very informative and useful -- and very similar to what the Miller-Stephenson literature suggests.
I wonder, though, about your conclusion #2 -- comparing the strength of a heat-cure to a 2 week room-temp cure. Based on the data you provided, it seems that 2 weeks at room temp. is probably not be enough time for the glue to reach a full cure. My understanding is that a heating regimen only accelerates the catalytic reaction needed for a cure, but does not alter the glue's final properties over conventional (non-oven) curing. Do any of you "chemical-heads" out there know about this?
But, the question is, what amount of time IS required, for a given mix-ratio, at room temp. to obtain a complete cure? (Concrete, for instance, requires several years, so it's not so great for fly rods.) All largely academic issues, since most of us probably will continue with our ovens. (Bill Harms)
Two weeks at room temp is probably adequate to achieve full strength. If you compare samples B & D you will see that they are nearly the same despite the fact that B was heat-cured. This implies that a 1:1 mix , which is overly rich in hardener, will achieve a certain strength either way. Whereas, a 2:1 mix, the perfect ratio for the chemical reaction, achieves the highest strength because of heat-curing.
The 1:1 mix achieves nearly complete reaction of the resin molecules by using excess hardener. That's why there is little difference between heat-cured and RT cured samples. But, the excess hardener is unreacted and acts like a lubricant between the molecules of cured material, reducing its ultimate strength but making it more flexible.
Unlike cement which relies on moisture to fully cure, the perfect ratio of resin to hardener molecules is necessary for maximum strength. However, If all of the molecules cannot come together to satisfy the chemical balance, then you never reach full cure. As the epoxy reaction proceeds, the material becomes thicker, thereby reducing the mobility of the molecules. At some point the viscosity is so high that reaction sites on the molecules cannot get together and you never reach a complete chemical reaction. Heating the material decreases viscosity, increases reactivity and thereby promotes a more complete chemical reaction. Something that cannot be achieved with time. (Al Baldauski)
Excellent information, and well explained!! A powerful case for the heat-cure regimen, as well as AGAINST using the 1:1 mix-ratio for our purposes. It sounds as if the 1:1 mix, aside from not reaching as complete a cure as the 2:1 ratio, may account for what some folks have called "creep" in epoxy glue lines -- a function of excess hardener continuing to serve as a "lubricant" between the other, cross-linked molecules. Not exactly what we want, and something that may allow for easier "sets" later on. (Bill Harms)
That's my conclusion. Although, higher strength from heat-curing leads to more difficult straightening. I don't know what happens to the structure of this epoxy when you significantly exceed the Heat Deflection Temperature. If there is a broad range of plasticity at elevated temperatures, before molecular breakdown, then straightening should be achievable.
I just found some additional data on the Reynolds Performance web site which supports your mix ratio of 1.5:1. For Epon 828, they have a list of 20 or 30 different kinds of curing agents. Under 3140, they recommend 1.5:1 as the preferred mix. At this ratio, the heat-cured material has a Heat Deflection temperature nearly 20 degrees C higher (115 degrees C) than at 2:1. This suggests that you get a greater percentage of cross linking at this ratio than at 2:1. This is possible since excess hardener provides more "available" cross linking sites when the epoxy becomes very viscous. The extra cross linking overcomes the "lubricating qualities" of the slight excess of hardener. They don't provide any other mechanical properties at this ratio, though.
So, 1.5:1 may be the optimum blend. Given this additional data I would tend to think so. (Al Baldauski)
Thanks, by the way, for your great demo of brush varnishing in Power Fibers a while ago; very clear and well presented.
I guess that what you say about variations in Epoxies and their hardeners will account for many variations in characteristics. I am using Epon with a locally supplied hardener whose alphanumeric designation I cannot now recall, and the ratio of mix is 3:1
I achieve what the company says is full cross-linking by curing in my fan-forced heat oven, and I am very happy with the final result.
However, my experience is that I can still straighten pretty easily at an time. In one recent case, I sold a rod to a friend and had obviously forgotten to straighten one tip- Senior Moment, I think- and he brought it back after a couple of months, at which time straightening was the work of but a few moments, using very little heat at Setting #2 on my Bosch heat gun.
He has, at my request, been preferentially fishing this tip hard since (I guess I was worried that I might have struck one of those sections one is always hearing about where they just take sets for no apparent reason) and the section is fine.
Must be the variation in formulation. (Peter McKean)
The last tip I had to straighten and untwist I tried a different trick: wrapped it in a towel and poured boiling water onto that. After a couple of minutes a cold iron unkinked it and the put it in the planing form and clamped it straight. There's no telling how many other tricks have been tried, perhaps incompetence is another mother of invention. (Henry Mitchell)
Talking of tricks for straightening I still use the tool mentioned by Max from Japan a few years ago, even though I do not remember the technical name.
It is a piece of 4" by 4" timer about 18" long with 3 grooves cut in one face. The grooves are about 1/2" deep and on mine one groove is about 1/4 " wide and the others 3/4" and 2" . The rod section is heated with the heat gun in the usual way until pliable and then slipped into one of the grooves. The groove holds the rod section enabling it to be bent to the required angle and it is easy to hold in place. It sounds complicated but is very easy to do. The different width grooves enable different angles to be obtained easily and the bulk of the wood provides stability which Peters "finger tweaking" does not always.
Try it on an old piece of wood with a rod section, it is surprising how easy it is to adjust angles. (Ian Kearney)
Tamegi - see here - the bamboo tips site, under contraptions, straightening devices. I use these sometimes on strips, but tend to rely more on the vise. (Chris Obuchowski)
I've arrived at a way of straightening glued-up tip sections in a fairly simple and easily undertaken method; it's actually derived from previously established methods. First I make some "bean bags" constructed from no. 7 1/2 or 8 lead bird shot put into athletic or tube socks. 3 athletic socks will take care of a tip section for a 7' rod. Then, take your metal planing form and cover with a sheet of saran wrap. Place the rod tip in the groove over the saran wrap and cover this with waxed paper. Place the "bean bags" over the rod section, this resulted in the straightest section I've ever had and doesn't appear to need any subsequent heat treatment. If your forms are narrow, you may need side bolsters to keep the bags from sliding off the form. I use Nyatex so I leave the bags on for only 1 1/2-2 days and then remove the wrapping string and either heat cure or let hang for a week or two. (David Haidak)
The only trouble with that is you can only do one section at a time, right? (Neil Savage)
I did similar with a rod sack filled with birdshot. My results were less impressive, but at this point I don't remember if it was an Epon rod or a Titebond III rod. 'course as a klutz I get special dispensations from the laws of physics and logic. (Henry Mitchell)
The trouble with all these methods, in my experience, is that if the section isn’t straight after you bind it up, it won’t be straight after the glue cures. If the binding string is too tight it won’t let the strips slide to a straight condition. Instead, what happens is you bend the strips straight when you weight them down in the form. When the glue cures and you take off the weights, the strip springs back to where it started. (Al Baldauski)
I whack my glued up sections. So far, I have been happy with the results. (Rob Clarke)
I've done a similar thing to straighten glued up strips. Set your forms for flat to flat measurements and put the bound strip in the groove. Spray on some mold release if you think it's necessary. I hold them down with lead ingots. Next day remove the binding string. Straight! (Don Schneider)
A few years back I wrote an article for "The Planing Form" describing a very similar method. (Instead of the metal planing form, I use lengths of 1" aluminum angle iron in which I place the glued up sections.)
To elaborate, one should purchase lengths of 1-inch angle iron that are at least as long as the rod section. After gluing, try to get the shaft as twist-free as possible. Then lay the freshly glued shaft in the groove of the angle iron. Cover it with Saran Wrap and spread 1 cup of lead birdshot along the length of the angle iron. Allow to dry and cure for at least 24 hours.
Remove the birdshot, throw away the Saran Wrap (which prevents the birdshot from getting under the rod shaft), and remove the rod shaft from the angle iron. Sight down the rod shaft, and it will be quite straight. Any remaining twists or curves will be minimal and can be easily reversed with an alcohol lamp or heat gun.
Note: For mid and butt sections...add a little more weight to keep them pressed flat against the walls of the angle iron. (Bernard Elser)
Just out of curiosity, do you use bird shot because it is available? Or because it is cheap? Obviously, because it is heavy. What alternative would be good? I don't shoot, but I guess I could find some bird shot somewhere. I doubt Berkeley has a gun shop. Oakland surely does. (Dan Zimmerlin)
I used birdshot because I walked into a sporting good store and they had some cheap because the bag was tearing. I think sand would be a good alternative. (Henry Mitchell)
Bird shot used to be cheap, but it is no longer. I would guess any dense material in a bag would work. The nice thing about bird shot is that it comes in a roughly 4" x 12" poly-burlap bag and when full weighs 25 pounds. If you could get a similar size bag, you could use silica or sand, just make sure the bag is tough and won't rip! (John Wagner)
I am curious, as a new rod maker, how you all straighten sections. As I make each rod, I realize that you are trying to produce straight strips from the start, I can appreciate it. Yet there always seems to be a section here or there that needs a little help once the final sanding is done.
How do you guys do it?
I am learning the alcohol lamp, mine is glass and I enjoy the aesthetic of it, but the noisy, ugly heat gun is a great tool for this job.
And while I'm at it, so you have straightened a section, for practical applications (read, for rods that will actually get fished regularly) will the straightening last? or is there original memory in the rod once it is bound that the section wants to return to?
I've made my first rods, I have not had the opportunity of time to answer my own questions and am posting this to the makers at this list who extensively fish their rods.
Thanks in advance and have had great fun reading some of the questions and answers. (Adam Trahan)
David Bolin's web site used to have an interesting little film of Harry Boyd straighten rod blanks that I found useful. Having said this, I looked at his site but it is no longer available. You might try to contacting Dave directly, watching someone do it was much easier to understand than trying to write how its done. (Don Green)
Here is a link that has the video I believe you were mentioning.
It is toward the bottom.
I watched that film and it was useful. The only problem I have is I still have trouble straightening blanks. Having never handled another bamboo rod other than those that I have made (which is only a couple), I wonder how straight every one else’s blanks are. I have a hard time getting them perfectly straight and it seems that I end up spending hours on each section pulling my hair out wondering how much improvement I'm making. My question on this is how straight is everyone else’s blanks and about how long does it take you to straighten a section assuming it is fairly straight out of the string? (Greg Reeves)
It's interesting that you state that you feel like pulling your hair out when straightening blanks. In Garrison's book he mentions that his wife had to frequently leave the room because, I presume, his blue language darkened the room.
The method I use, which is not mine by origin, is to not bind the section too tightly at glue up. You'll find that, takes care of 90% of the warp in the stick. I usually wrap my guides soon after straightening and that seems to help keep the section straight. Anyway that's my two cents worth. (Mark Dyba)
Straight is kinda like pregnant, either it is or it isn't. Whether or not a rod stays that way is another thing, it depends on a lot of things, the bamboo, how hard it's used and the care taken of it, the climate it lives in and if you actually got the fibers reset or if you just bent them straight without getting them hot enough. (John Channer)
I don't think the rod has to be perfectly straight to cast effectively. If you're gettin' a thousand bucks for it, it should be perfectly straight. I've had a couple rods go from damn straight when finished back to some familiar crooks after fishing it over time. You'll learn by your mistakes. (Chad Wigham)
I use a heat gun to get the strips as straight as possible. Then After I glue the strips into a blank, I immediately place the section in my planing form and wrap the form and the blank inside it tightly with plastic wrap. There is Saran wrap and then there is a product called "stretch-tite" which is even better.
NOTE -- Before I set the blank into the form, I place a long sheet of saran wrap down the length of the groove in the form to protect it from the glue. I wrap the blank throughout its length and try to get it as tight as possible. Take extra care on the tip. After the glue sets, I cut the plastic off and remove the blank and hang it until it is fully cured.
An extra step that I plan to try on my next blank is to apply some heat to the plastic wrap to give a shrink wrap effect in hopes that it will tighten the (thus straighten) the blank even more.
I have done it this way for my last two rods. I think I got the idea form someone here.
This works pretty well for me except for the part when my wife asks, "what happened to the all the plastic wrap!"
In my first few rods, I found that my tip sections got screwed up under the pressure of the binding string and I spent a heck of a lot of time trying straighten it with a heat gun and iron. (Matt Baun)
I suppose a few rods ago I was just where some of you are now -- scratching my head in search of the perfect answer for straight strips. On my last three rods, I thought I had found it. Perfect tension on the binder, and strap the sections to Heat Treating Fixtures while heat setting the glue. Going in, everything looked perfect.
After removing the binding cord I found that each of the six tip sections had a half twist running from one end to the other. After getting those twists out, those tips were crooked as snakes. Each of the three mids had a coupla little kinks here and there. Two of the three butt sections required some straightening just ahead of the swelled butts.
Total time for all the straightening? Probably an hour. Maybe 1.5 hours. It just isn't that hard, folks. Don't make this into rocket surgery. Heat the doggone thing till it's almost too hot to touch. Bend it to an inverse of the current bend, and hold till it cools. That's all there is to it.
Watch the video here.
I'm thinking of setting out a shingle which says:
- Bamboo Rods Straightened -- $100
- Bamboo Rods wrapped -- $100
- Ferrules fitted -- $100
Think I'd make any money? (Harry Boyd)
CNC beveled strips - priceless. (Larry Tusoni)
As a personal side note
I, unlike the majority on this list, after about 100 rods, still found that I was not capable of holding .001 tolerances with a chisel and a set of steel bars. After I got over the rage of cloning everyone else's rods and wanted to see what rods were really all about, I concluded that accuracy was more important than close enough. Sure I could sell anything that said Payne, and no-one could discern the differences, I knew. When my numbers were not consistent I had no way to evaluate (repeat) the rod.
Yes Larry, I would buy a CNC strip from Harry before I purchased a whittled one. (LOLouder) (Jerry Foster)
Now yer talkin'... We'll get you cave men into the 21st century. Eventually. (Mark Wendt)
I still use the initial step after gluing of "whacking" the glued up blank on a long flat hard Board. I think it was a suggestion from Max in Japan a few years ago. I still sometimes have some twists and slow bends in the blank , but seldom something that cannot be removed in more then a few minutes.
I use a five foot by two foot length of MDF board . The technique involves holding the bound blank, while the glue is still wet , by the thickest end and whacking it down in the board from a height of about 18 inches. The idea is try to have the whole length of the blank hit the board at the same time with a decent Whack. This seems to relieve an tensions or unevenness in tension in the blank and nestle the strips in evenly .
Like many of the comments on here this works for me , but maybe not for others. (Ian Kearney)
My problem is I seem to over bend and then I keep chasing my tail. Finally I think I have it and move down the blank some more and straighten a kink and then chase my tail some more. Think I have it and roll the blank a few more times and realize the tip is jumping back off of the glass. Maybe I’m not heating enough or maybe I’m just giving up to early. I’ll watch the video again for inspiration and then go home tonight and straighten some more. I really would like to produce a nice straight blank. Do you not stop straightening until you see 0 light beneath the strip on all 6 flats or do you settle? (Greg Reeves)
FWIW, I try to not see any light beneath the 6 corners of the section ~ Hi Ho!
AND, with respect (respectfully), to all of this, including the tapering processes, etc., one might wonder what a trout might say about what it thinks ~ if a trout could think? Try to remember to ask if you should meet up with one next Tuesday (EDST). (Vince Brannick)
One thing you might try is taking a scrap piece and playing with it--heat it and put a bend in, let it cool and try to straighten etc. It took me a while to get the feel of the bamboo when it was ready to straighten. (Neil Savage)
I've tried helping someone to learn how to heat straighten, but as Harry says, stick with it. This is one of the most subjective processes in our craft. A simple concept -- just heat and counter-bend, right? No, it takes a bit of learning and after a while one develops a sense of how much heat, how much bending, how narrow or wide to make your bend, even finding the right place to make the bend. Hang in there. Be patient and tell yourself that this task is just as necessary as planing or any of the other steps. (Steve Weiss)
I use a pre-owned clothes iron I bought at a local thrift shop for a couple of bucks. I lay the section or strip in my form and use the iron to heat it. I gently lift the strip in the direction I want it to bend (or not to bend). I can get strips and sections pretty darn straight by doing it this way.
I have also used a heat gun but the iron seems to work the best. (David Gerich)
Over the course of 65 or so rods I've tried every trick anybody has ever mentioned to produce straight sections, none of them made much difference for me. No matter what , it always seems to take the heat gun and some effort to get them straight. Using a glue which gives you some time to mess with the freshly glued blank helps, getting your binder just right helps and developing a feel for what you're doing helps most of all. You can fool yourself with bamboo and get it what appears to be straight now, but you look at it again the next day and the same old bends are back, this means you didn't get enough heat in it in the first place and it didn't get soft enough to realign in the new position. I found out the hard way that you can scorch a blank much easier with an alcohol lamp than a variable output heat gun, gauge the amount of heat to the size of the section you are working on, tips need just a touch of warm air, butts need a blast of hot air, but keep the section moving.
Good luck! (John Channer)
I have discovered a really useful final straightening technique. One of the perennial problems I have with straightening is keeping the rod section perfectly in line on one plane while counterflexing the bends out in the other plane (which is at 90 degrees). This is most tricky for tighter bends in the tip section as the thicker end of the section tends to be difficult to support. I like to see exactly how much I am counterflexing and thus can’t check that I am not putting in a new bend in the other plane. I figured if I could get a flat hot bed to work on it might be easier.
So this is what I did…..
I got a piece of 3“x 1.5” rectangular aluminum tube 6’ long placing the tube wide side down on the bench - (in fact I used a channel simply placed on a board, because I didn’t have a tube at hand). I then bolted (or you could rivet) a 4’ long 1”x1” aluminum angle on top of the tube leaving 1’ of tube extending beyond each end of the angle. The toe of the angle is bolted in line with the edge of the tube so that the vertical of the angle effectively makes a vertical ‘fence’ running 1” in from the edge of the tube. Something like this in cross section:
The angle could just as easily be a 1”x1” channel or flat. The idea is to get a straight fence to work against.
I then scored a line along the fence and extended it the last foot to the end of the tube on both ends.
The straightening procedure is
1. Put a heat gun into the one end of the tube and heat it up like a heat-gun-oven adjusting the temperature on the gun until the tube is almost too hot to touch.
2. Warm the section up on the tube rotating it every now and again (you can warm the sections up in a drying cabinet first if you are going to be doing a whole bunch). Place the thicker end nearer to the heat gun
3. First do some quick eyeball basic straightening getting the major sweeps and twists out.
4. Place the rod section up against the fence leaving 2” of the tip projecting past the end of the fence.
5. Place another loose 1’ long piece of 1”x1” angle (effectively a moveable fence) up against the section with the end of the two fences more or less in line with each other. Hold the section firmly in place by ‘clamping’ the two fences together in your one hand - make sure the rod section is lying flat against the aluminium tube (the rod section can rotate off the flat you are busy with if you squeeze it too tightly – if necessary press the projecting section down with your index finger at the end of the fence).
6. Now counterflex the 2” projecting rod section horizontally round the end of whichever fence is necessary keeping the section flat against the tube. Hold it for a couple of seconds. Repeat until the rod section lines up with the score line on the aluminium tube.
7. Slide the rod section along so that another 2” projects past the end of the fence and repeat … and so on for the whole length. This goes quite quickly. You can flip the rod section end for end if necessary and can also use either end of the tube. The end that is closer to the heat gun is obviously hotter and is better for the thicker end of the rod section.
8. You can do one flat at a time or each flat in turn every 2”. The latter is probably better as the rotation keeps the whole section warmer.
Make sure you smooth off the corners at the ends of the fences so that they don’t scratch or damage the blank. The fences get quite warm themselves so it might be worthwhile adding some sort of insulating material where you grip them. (Stephen Dugmore)
..…forgot to add that you can obviously place the flats against the fences – just work quickly when doing so and keep the section warm by allowing it to lie flat down on the tube every now and again. (Stephen Dugmore)
I'm working on wrapping the guides on a couple of spinning rods and noticed a slight twist and curve in the tip sections. No problem, just warm them and straighten! But, these were glued up with Epon 828/3140. I'm more used to Nyatex and it seems Epon takes a lot more heat to straighten.
The rods have been finished before the guides were wrapped. So, what's the danger of damaging finish while straightening these sections. (David Dziadosz)
Just keep the varnish cool enough that you can hold it, bare handed, and you should be fine. (Harry Boyd)
For me, this is probably the most "Nerve Racking" phase of rodmaking. Final straightening!!! Bends and twists you can't see till the guides are wrapped.
Nobody wants a bend in the rod, till there's a fish on the end of the line!!! Maybe we could say they come pre-bent! Twists are extra!! (David Dziadosz)
I use Epon 828 and Epicure 3140 and I don't have much trouble straightening them and yes, you can straighten after you've varnished the rod, you just have to be darn careful! Use low heat, heat for a longer time and don't touch the varnish until it cools and you'll be all right. This is another of the many reasons I prefer to varnish the rod after the guides are wrapped, having the guides on helps me spot any slight bends or twists that I might have missed before. (John Channer)
I too, find straightening a rod to be the most challenging part of the whole rodmaking process but I am sure I will get it right some day. I also use Epon now and have run into this problem.
There is one tip that I will share with you concerning bends & twists that show up after the guides are wrapped and that is to temporarily put the guides on prior to finish work but only put them on with heat shrink tubing or masking tape. Then you can sight down the rod and the guides will show you where your problem areas are and they can be eliminated and the guides removed if you desire. The advantage is that you don't have to worry about the varnish.
For me this helps a great deal because I have several vision problems and it is easier to see the alignment of the guides than just the bare blank. (Dick Steinbach)
Do you blokes have Blu Tac? It's a pale blue sort of putty that you use for sticking stuff on walls etc.
I like to varnish my rods before I wrap on the guides. I prefer it this way round as I can then get a good long sweep with the leather pads I use for the Perfect It 1 & 2 and the Finesse It, with no fiddly buggerising around with guides and wraps. However the point about straightening is very true. What I do is, before I polish the varnish, I stick a series of small (1 mm) pieces of Blu Tac in place of the guides, very approximately, and these allow me to get a sort of sight along the section. They just pull off afterwards and can be used again and again.
Simple thing, but it works, and it means that any minor irregularities that I cause in the varnish due to heating, can still be polished out prior to wrapping.
Now, of course, the only difficulty is managing to pack the wraps satisfactorily when wrapping over a spar varnished surface. That really IS a nuisance! (Peter McKean)
This is another of the many reasons I prefer to varnish the rod after the guides are wrapped, having the guides on helps me spot any slight bends or twists that I might have missed before.
I agree for the most part, I usually do a final dip after the guides are wrapped and final straightening is done on a fly rod. These are spinning rods and the guides won't fit in the dip tube. (David Dziadosz)
A week or two ago there was a thread about twists in rod sections. Don Andersen said, "Still twists occur. Ron Grantham showed me a neat trick that he demonstrated @ Merritt last year.”
I've been having trouble posting to the list and haven't been able to get my two cents in so I'll try once more.
Here's what I do:
Lay a piece of masking tape about two inches long across one end of a sanded rod section and bring the ends together to make a protruding tag. Then lay the rod section on a flat, smooth surface with the tag somewhat vertical and run a hard, smooth item, such as a piece of bamboo or the flat side of a steel ruler, along the rod section's length, all the time watching the tag. If the tag moves, there is a twist in the rod section. By moving your hand back and forth you can determine exactly where the twist begins and ends. This will work with quads, pents, hexes or whatever.
When checking for bends, sight down the rod section in the usual manner. Put your thumb on the bend the way you would for straightening and check the position of the tag. After rotating the section over the heat, point the tag in the predetermined position and you'll know which way to apply pressure without having to sight down it again. (Ron Grantham)
I have built 2 blanks using TBII & they need a little tweaking to make them straight. I usually use Nyatex to glue rods & I know how much heat it takes to straighten a rod using this but have no idea how much or how little heat I need for the TBII to work the rods. So you guys who have used this what are your recommendations for the application of heat so I can get the slight bends out of the blanks?
I have a lot of time making these & do not want to bugger them up & delaminate them. I am open to any & all suggestions for this. (Bret Reiter)
I have used nothing but Titebond. I never heat more than necessary, but I don't heat too much to begin with. I never take it warmer than I can comfortably touch. I have, what I consider over heated a couple of sections, and have not had any problems with a section delaminating. In other words, moderation.
Rule of thumb is if you can touch it for approximately 10 second, and that's it, it is around 150 degrees f. (Pete Emmel)
Something I've discovered which probably others already have been doing: I've found that the inevitable twists in the sections are more easily identifiable for me if I put #2 or #3 snakes on about every foot or so and then sight down the rod, heat and counter twist. If the guides all line up it's then easy to straighten the one-dimensional problems. I use old nylon thread and just wrap one foot usually. The guides are removed of course after straightening. It seems that if the twists are not first addressed, I have a heck of a time. (Dave Kemp)
That works very well, it is the way I do my final straightening. I usually do it after the guides are wrapped. If heat is too close to the wrap, I use a wet paper towel to protect the wrap. I can look through the "tunnel" of the guides to do the lining up. A twist stands out like a sore thumb. (Tony Spezio)
I wrap a length of masking tape around one end of the blank and stick the ends together so they stand out perpendicular like a flag. Then, with the blank laying on a smooth, flat surface, I slide a piece of bamboo along one flat while watching the masking tape. If it moves, I have discovered a twist and I can locate the exact start and end of the twist by moving the piece of bamboo back and forth. (Ron Grantham)