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< Home < Tips Area < Machines < Bevelers < Baginski For those using Baginski Bevelers, there is a problem cutting strips that will lay flat on conical surface of the wheel without wrinkling. I came across a link with a discussion of the geometry. The surface is technically speaking the frustum of a cone. Reduced to the situation of interest to rodmakers, one draws two concentric circles on the back of the sandpaper with a compass. For the 60 degree strips the inner radius R1 is 1.1155 times the inner radius of wheel and the outer radius is 1.1155 times the outer radius of it. A 48 degree pie slice out of it will have the ends just meeting without overlap. For a quad strip beveler, the factor would be 1.414 with a 105 degree slice, and for a penta strip beveler the factor would be 1.236 with a 69 degree slice. I have used epoxy, Barge cement (contact cement) and adhesive backed sandpaper and they all worked fine. Heating the disks with a heat gun works for getting off worn out paper. I have updated my page on implementing a beveler with this information. (Mike McGuire) That looks like it worked out perfectly. Great info. I tried this for the first time just recently. I painted the bevel of the disk and rolled it on the back of the sandpaper. I cut this out and epoxied on. Didn't work so hot. I ended up just putting ~1 cm strips spaced ~1 cm apart along both bevels. They fit together well (the paper doesn't push against paper at the apex) and I figure it will allow better clearing of material. I'm not sure either of those points are an issue with these bevelers, but it certainly simplified the gluing process. I haven't completed the unit yet, so no info on results. Maybe it will be too short on cutting power... (Conor McKenna) In my article about the beveler, I included a couple of drawings showing how to use a geometric projection method to make the pattern for the abrasive. It seems like I am the only person who understands that method! The alternative I have suggested otherwise is simply placing (or taping) a piece of paper on the conical surface of one of the disks and marking the edges on the paper. Beats the paint method, because you can see if the paper is properly arranged on the conical surface. The paper need only cover part of the conical surface. I find using several sections of abrasive easier than trying to get a single piece to fit properly. Very small gaps do not seem to matter, so long as the glue is strong enough. I use the same heat-settable epoxy that I use for building blanks. I do not heat set it, but figure that maybe it will stick even tighter if it gets hot! Rolf Baginski says that he gets about the equivalent of 60 rods from one application of abrasive to his wheels. He uses the same epoxy I do to glue on the abrasive. We both use the abrasive from a belt-sander belt. (Tim Anderson) I have recently worked out an implementation of a Baginski Beveler based on a Harbor Freight bench grinder. It turned out rather nice and compact, so I did up a page on my personal site describing it, including how I machined the cutting wheel. It's sure a lot quieter than the Medved Beveler I was using. A beveling session no longer drives my s.o. out of the house. It's faster, and no burn marks, no chatter marks, no destroyed strips. (Mike McGuire) Does anyone know of plans for Rolf Baginski rough mill sounds interesting. (John Jones) You will find my article on the Baginski beveller in Power Fibers (Issue 36). There are no specific plans there, but you should find enough information to build the device. (Tim Anderson) I saw the article and think I may build one this winter. How often does the sandpaper have to be replaced on the grinding wheel? (Greg Reeves) The abrasive lasts a long time. You will notice that I tried to avoid calling it "sandpaper" in the article because I think the sanding-belt material is better than paper backed abrasive. After several rods using my wheel, I can see no indication that the abrasive has degraded in any way. Rolf Baginski is a commercial builder with quite a high output and uses his wheel for all of them. He has not mentioned needing to replace the abrasive often. (Tim Anderson) I asked Rolf about that. I believe he said he gets about 6 rods out of the abrasive discs. I have seen Rolf's machine working. It does a nice job, and is very quick. (Tom Smithwick) I have used my disk for about 5 rods (4 of mine and one of a friend) and still see no sign that the abrasive needs replacing. The difference may be that I run my disk at about 2500 rpm and Rolf runs his at 10,000 rpm. In addition, I usually make about 3 passes per strip while Rolf commonly takes a strip down to its final rough dimension in one pass. As a commercial builder, he saves time with his procedure, especially since he has a few spare disks lined up. I believe the machine Tom saw was Rolf's original model which he now uses for his rodbuilding classes. (Tim Anderson) What grit is appropriate for the wheel?? (Roland Cote) It is in issue 36 of Power Fibers Article. I believe it is 36 or 50 grit. (Greg Reeves) As the author of that article, I am happy to confirm that 36-50 grit is the recommendation. (Tim Anderson) Just for your information, I saw the type of beveler more then 16 years ago at a Dutch rodbuilders group in Venlo, Netherland. It has also been shown on a Fly Fair in Zwolle, Netherland. As for the rod winding machine where Piet Veugeler is the inventor it might well be that he also invented the mill. (Christian Meinke) Rolf never claimed to be the inventor. As I mentioned in the article, he simply does not know if somebody else made it before him. Of course, it is entirely possible that the beveler you saw in the Netherlands was Rolf's. At about that time he regularly attended rodbuilders' meetings in the Netherlands and he also has good friends among the Dutch rodbuilding group who could have picked up the idea from him. As an aside, you will find a picture of him at one of those meetings in his book! (Tim Anderson) Has anyone built a Baginski Beveler profiled in issue 36 of Power Fibers? It seems like a rather easy version of a roughing beveler to construct as well as operate. The only part that is confusing to me concerns the abrasive strips for the wheels. What is the process to cut the strips to fit the wheels? (Ron Delesky) It seems a number of people have. There is a discussion on Clarks List that I just added to today, so you should be able to find it easily. The article shows how to make a pattern for the strips, but it seems that most people can't figure out what the heck I was showing. The easiest way to make the pattern is to lay a piece of paper on the conical part of one-half of the disk and mark out the shape. Make the total curve out of several pieces. Cutting the abrasive is easy. As mentioned in the article, belt-sander belts are the best source of durable abrasive. Cut such a belt so it lays flat, mark the pattern on the cloth back, and cut with a box knife along the marked lines. Do not try to cut through, all you want to do is cut most of the fibers in the cloth. After cutting around the pattern lines, bend the belt material and it will break along the scored lines. (Tim Anderson) I found as Tim suggests is to make the discs and use them as templates. I actually made a copy of Tim's beveler using my Shopsmith also, Works like a darn. However I have found after the first discs using 6-7 sections of strips that it is better to minimize the pieces used, and since I am using belts from my Shopsmith which are about 36x 6 it is easy to cut as little as 2 strips for each disc, I now have have a spare set of discs, and back up strips as needed, it saves set up time if one fails. (Keith Paskin) I just started using my Baginski beveler last night for the first time. The paper cutting process was a bit of a pain for me. The article has diagrams to describe it better than I will here, but sometimes some things click differently for folks. You'll need a compass like geometry class or woodworking to draw a circle, or a string and a tack and a pencil. You'll need cloth backed sand paper, coarse as you can get. Got mine at the Fastenall store. And a pair of scissors that you are ok with ruining. The radius of the circle of the paper needs to be about 5/4 ths of the radius of the piece of wood that you will be mounting it on for a 60 degree beveler. Scribe a circle that size on the paper and then scribe a circle inside that. The two concentric circles should be larger than the cutting surface of your wheel. Then cut along the outer line, and make a cut into the circle so you can cut out the inner circle. Then you can lay that on the cutting surface of the wheel and fiddle with it until it lays correctly on that angled cutting surface. I used 5 minute epoxy and gooped up the paper and the wheel and then glued it on. So far, it works like a champ, but it is quite dusty. Just try it with regular paper first, then it will make sense. I kept my paper one as a template from here on out. (John Wagner) Has anyone built a Baginski beveler? What are the pros and cons over using a router based beveler such as a Medved style beveler? How accurate are the angles on the strips? (Derrick Diffenderfer) If you do not have my article about the Baginski beveler, let me know and I will send you a copy. The article describes the advantages, many of which are a result of both sides being cut (actually abraded) at the same time. The angles are as perfect as the angles of the abrasive wheel. It is a rough beveler and, since the cane is abraded away, the smoothness of the resultant surfaces is dependent on the roughness of the abrasive on the disk. That abrasive needs to be fairly coarse. I show pictures in the article of my Shopsmith-based Baginski beveler. I now have built and use one which is based on a router. (Tim Anderson) I've just made one to try to use with my drill press via an attachment to the table that I made up. The biggest problem I'm having at this point is getting the sandpaper to stay on the plywood wheel. I'm using a 3M spray adhesive but I have had a section come off now and then. What is a good adhesive for the sandpaper to plywood wheel? Should I put a coat of varnish on the plywood wheel grooves to give the adhesive a better surface to bite? (Mike Monsos) I recommend epoxy and a type more heat resistant than the usual 5-minute epoxy. If you use the 3M 90 spray adhesive, varnish on the plywood might help. (Tim Anderson) On the topic of a Baginski beveller, I tried one and found the sandpaper clogged up with semi burnt material very quickly. What do you think I was doing wrong? Too fast? What is the ideal grit? (Stephen Dugmore) You really need to use at least a 36 grit strip cut from a belt sander belt. Also take a lighter pass and figure about 45 seconds per pass on a strip. I take about five passes to go from a .270" wide strip to a .210" flat to apex strip ready for binding and heat treating. (Mike Monsos) I use open coat 40 grit paper (green stuff) that I buy from an auto body supply store, green stuff, works great, not inexpensive but it lasts a long time. I buy the 2 1/2 in air file stuff. I only do one pass per strip and bind and heat treat the strips. Oh yeah and Mike Monsos wheels are the ONLY way to go! Design your beveler around these wheels! BTW, if you have a store near by or you look around you can buy it in smaller quantities. (Joe Arguello) Are you on the level in saying you do only one pass per strip. Trying to recall the last strips I did, but I think I went from .200 down to .160 on the butts and make 5 or 6 passes. I am using the red stuff; 50 grit I get at the hardware store. You are saying that the 40 grit green stuff will do that much better, correct. (Lew Boyko) Not ever seeing the Baginski beveler it intrigues me as to how well it works. I have used the Medved beveler & it works well. I ended up getting Hal Bacon's beveler some years back after seeing it @SRG. I like how it cuts both sides @ a time. (Bret Reiter) There are products for clean gum/gunk off woodworking tools that work well for cleaning beveler wheels such as this on. Here is a before and after picture of using it. It greatly extends the life of the grit. And as others have said a fairly coarse grit, under 50 works best. (Mike McGuire) Thanks for all the advice. What sort of rpm’s are you guys using? (Stephen Dugmore) I have mine mounted on my old Sears Craftsman 6" bench grinder that turns about 3400 RPM. I like the 36 grit belts myself. I am experimenting with 16 grit silicon carbide and JB Weld as a bonding agent. (Mike Monsos) If it is any help, I use 40 grit abrasive on the 3” diameter wheel of my present Baginski beveler. A large adjustable-speed Makita router turns the wheel at its lowest speed setting which the manufacturer gives as 9000 rpm at no load. I take split strips (square cross-section) from about 0.32” to 0.25” wide in three passes. That does not put the router under much load and I feed the strips into and out of the router quite gently. My latest abrasive is from blue-colored sanding belts from Harbor Freight. The stuff lasts very well without loading up excessively. I now glue the abrasive onto the wheel with slow-cure superglue gel. Rolf Baginski, who invented the beveler, uses epoxy to glue the abrasive onto the wheel. Getting the abrasive off the wheel (to change grit or whatever) is easy. Just use a torch to heat the aluminum of a wheel half and the stuff pops right off. Of course, don’t try that when the wheel is still mounted on the drive motor! (Tim Anderson) |