Q & A
- Volume 1, May '98
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Q & A - Volume 1, May '98
Ian Bruce asks: I have been building a radical deflex-recurve laminated using the Perry principal of inner-limb energy storage (I use three laminates, gluing up the belly and core on one jig to pre-load the laminates then laminating on the back on a second jig). The working recurves are so severe that twist is a problem and I would like to know if you are aware of a glue that would stand up to steaming so that I can adjust the limbs a little if they are misbehaving. I have tried Gorilla glue, and a test piece stood up to both steaming and dry heat bending, but the glue itself let me down by totally delaminating (in a joint that had not been steamed). Surface preparation was not the problem (though I have had trouble with "planer burnished" maple and epoxy)--I was able to separate the failed glue-line with a putty knife for the entire length of the limb and both surfaces had held the glue--the glue itself had failed. I know that epoxy is not a good bet for steaming and neither is yellow glue. I have never used hide glue but I understand that it too softens with heat. I would appreciate any ideas you might have--I do like this bow design for all that it is tricky to tiller!
P.S. I reglued the failed laminate with epoxy and saved the bow but it pulls fifty instead of sixty pounds and the finish is starting to crack along the Gorilla glued laminate in the riser.
Dean Torges: Ian, my experiences with Gorilla Glue are similar to yours. I pitched the stuff in a waste bucket several years ago. Wrote long note explaining failures and asking questions of the importer in California, but got no attempt at explanation whatsoever, only defensive posturing. It's not like I never used glue before, either.
Resorcinol is what you require. Do not measure it by volume but by gram weight. Downside is that it leaves a glue line, exaggerated in appearance because of its purple color. It holds, has excellent gap filling properties, it holds, is easily available and it holds.
Resorcinol and Urac 185 are about the only wood to wood glues I use on bows anymore. Am done with painful experiments in these matters.
Herk asks: I have an osage stave that suffers propeller syndrome. All the twist is in the center of the stave, leaving "straight" limbs. I prefer a narrow, deep handle. Would this handle be hard to straighten? It appears that if I go ahead and make the bow as is, it will be twisted, but near center shot. Would the twist affect cast? Accuracy? Maybe this would be a better candidate for the takedown I've always wanted to make?
Paul Comstock: I would cite for you the example described by Robert Elmer in his "Archery" book of the 1920's. A friend of his made only two bows and gave Elmer the second. It was an osage bow which Elmer said was so twisted and crooked that it turned half sideways when drawn. Elmer used this bow to win a flight shoot (so the cast was excellent) and also shoot over 1,000 in the double York round, a superb score for that time (so it was very accurate). My experience matches Elmer's: The result is only cosmetic, 99 percent of the time. Inexperienced archers, however, may have trouble shooting well with such bows. To my knowledge, there is only one really reliable way to fix twist: Steam the untillered stave, clamp it in a vise, cut a rectangular notch in the side of a 2x4 and use the board as a big wrench to twist the thing straight. Murray Gaskins shows this in one of his videos. Be warned though: If you are already shooting the bow, it's probably too late. My experience is any steaming must be done before the bow is tillered, or else the bow will resume its previous shape.
Bamboozled in New York asks: I have recently finished a bamboo-backed hickory bow and would like to know what to do with the bamboo prior to finishing. The skin side of the bamboo doesn't look like it will take a finish as it is, and what about the nodes? Can I shave them down a little without causing damage. If so how far?
Dean Torges: Keith, use a file to lightly clean off the thin, brittle lip that runs across the node, cleaning up the node in the process. Keep the node in its original crowned shape, however. Think of it as a broken bone knit together which requires its bulge to maintain its strength. Then use your cabinet scraper to clean off the rind between nodes, wiping over each node as well to remove file marks. You should work down to a uniform shiny golden yellow color. Wipe from the rind into the cleaned area so that you erase scraper "bite marks" as you proceed. Sand the surface lightly after it has been scraped.
Stains and dyes do not take well to bamboo, though I use them anyway (carefully, so as not to lift preceding coats). Any orthodox finish adheres well. Even paraffin works.
Greg Davis asks: What the best wood is for a self bow?
Paul Comstock: That question can be answered in several ways. One way is to ask in return, "Why do you want to know?" For example, one might be looking for a wood that is so "good" that the bow would be easier to make, when compared to a "less good" wood. There is no wood that is so "good" that it can overcome poor workmanship and poor design. It is possible to make a miserable bow out of osage orange or yew, which are traditionally considered the "best" woods. There is something to that reputation, because osage and yew have high compression strengths — higher than almost any other wood you can use. >From a practical standpoint, this means the osage and yew bows can be on the narrow or short side, or both, and still yield excellent results. But only if the bow maker does an excellent job. I think the best answer to this question is: The best wood is the wood can obtain in large amounts. White ash, any elm, any hickory, or hard rock (sugar) maple can consistently produce self bows that will equal a self osage or yew. But only if the bow maker does an excellent job and uses the right design. He will need to avoid making the bows too short or too narrow.
Some woods are even fussier than white ash, elm, etc. To get good results from birch, for example, usually will require a longer design than a similar bow of elm. Black locust has a reputation for being a good wood, but it often frets and breaks very easily. Yet outstanding bows can consistently be made of birch and black locust. But only if the bow maker does an excellent job. It is possible to make a fine bow out of a lousy piece of wood, and a lousy bow out of a fine piece of wood. For more than 8 years I have been using a bow made from a piece of red elm that was, technically speaking, decomposed. It wasn't too decomposed though, just enough to create small frets on the belly where spring growth is exposed. This bow has been used heavily and will, I believe, pretty much last forever. One might conclude that elm is the best bow wood you could get. Well, it could be.
Joe Catanzariti asks: Recently visited the Fred Bear Museum in Gainesville Fl. and had a chance to view many of the early Nels Grumley Bows. These bows range from English longbows to flatbows, to static recurves. Some are selfbows backed with sinew or rawhide, many are wood composites. Almost all have the distinguishing feature of the famous brush nocks. While these nocks look kind of neat and I have no doubt that they would help keep brush from getting snagged between the limbs and the bowstring, would they not also be a big drag on performance because of the obvious extra weight at the tips ? Also is there any other redeeming value to this type of nock.
Dean Torges: I assumed the same as you, Joe, until I read in "Archery: The Technical Side" about experiments with the effect of weight and air resistance from bow tips upon cast. C. N. Hickman fastened brass washers in increments of about 50 grs, up to almost 200 grs., to each tip (totaling 400 grs), and shot variously weighted arrows (from 271 grs to 663) through a light bow mounted in a shooting machine. He found that a load of 400 grs added to arrow weight reduced velocity by about 42 fps, or 25 %, but the same 400 gr. load to the tips reduced the velocity even for light arrows by only 1 %. Defies common sense, does it not?
He also screwed "fans" to the tips, tangential to the growth rings, increasing them in size from 2 sq. in. in increments up to a total of eight square inches upon both tips. The results were about the same and equally surprising, amounting to a 2 fps reduction in speed for the largest fan, proving that the cast of a bow is not reduced appreciably by air resistance on the bow tips either.
So, English longbows or static recurves, tip weight seems to have little affect upon performance.
Joe Mattingly asks: I've just harvested some Osage staves from bodark trees knocked over by bulldozers. I'm wondering how to set them up for long-term curing and would like to eliminate the threat of borers or checking. I've painted the ends of the staves, but the staves from one of the logs have all the bark removed, apparently when the bulldozer hit it. The sapwood is still intact. Can I leave these staves like this, or should I remove the sapwood? Do you think leaving the sapwood on and exposed will cause checking? The staves from the other log have both bark and sapwood still intact. Should I leave these alone, or reduce down to heartwood? Thanks.
Joe Don Jones: Joe, I'll give you my technique for preparing osage wood for seasoning and protection of the dreaded wood borer's. After I've harvested some osage the first thing I do is split the stave and then quarter it up, then I draw knife the bark off leaving the sap wood alone, you'll find the bark will come off pretty easy. Next I lay all staves on 2 or 3 saw horses and brush on varnish or some cheap lacquer just on the back and the ends of the staves. By doing this you will eliminate all possibilities of the borer laying eggs in the bark and at the same time you will get a better look at the grain of the staves. Once you've taken the bark off you must care for the staves as quickly as possible with this or a similar method to keep the wood from drying too fast and checking. This method has worked for me for the last 4 years without any checking and borer attacks.
Ed McNett asks: I'd like a basic list of hand tools the "novice" builder should have, besides a pocket knife and hatchet, in order to do a respectful job in hacking out a bow.
Dean Torges: A bowyer's toolbox does not require many items or much expense, especially for self bows. A drawknife and spokeshave remove waste wood quickly, and a rasp, such as the Nicholson # 50 shape wood deftly, without clogging. Beyond these, a cabinet scraper or a Bowyer's Edge are excellent finesse tools for scraping backs down to one growth ring and for tillering, and a little 4" rattail bastard makes an excellent nock file.
J. Dern asks: Can you build bows from green wood?
Murray Gaskins: Absolutely, and the bows that you build will be just as good as any bow ever built from wood that has been "cured" a traditionally accepted period of time by traditional methods. Green wood is much easier to work to dimension than dry wood is. The roughed out green wood bow can be dried and shooting within about 10-14 days of being cut from a standing tree. If you would like to investigate the green wood bow theory for yourself, you should get a copy of Paul Comstock's book, THE BENT STICK and read it. When you put the information in the book into practice you will have a very different impression of the old theories.
Buy this book Here!
The Stickbow's very own Dean Torges has authored his first book - Hunting the Osage Bow A must for anyone with a traditional library or a inkling to shave a stave!
Check out Dean's site at www.stickbow.com/torges
