Q & A
- Volume 3, Fall '98
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Q & A - Volume 3, Fall '98
Volume 1
Tim Flood asks:
How do you get the leather grip to fit so well on carved up handles?
Do you glue it down besides sewing it tight?
Dean Torges: Some leathers, like purse leather, stretch and conform to contours. Some, like pigskin, don't. Some, like vegetable tanned, can be dampened and then stretched to dry over the handle before they are glued in place. If your handle has shape, you will have to search out a compatible leather.
I use solvent based contact cement on all leather handles, applied to both the leather and the handle, gluing it in place before sewing it. Contact cement makes leather a little more supple, aiding in stretching it over uneven shapes.
A mulberry question from Mr. Craven:
I cut down a mulberry tree, carried the trunk to my shop and now it is sprouting. Should I be alarmed? Please tell me a little more about mulberry as a bow wood.
Murray Gaskins: I've had mulberry do that when cut in the spring or summer. You need to split the log and reduce the moisture in the wood, below the level necessary for it to survive and grow. That log has sealed itself and has plans for making it past this little inconvenience you have imposed on it. You can cut the piece off with the sprout, plant it and grow some more trees if you like.
I personally like both species of mulberry—red and white—that I have used so far. They both have been very similar in performance. Mulberry is flexible, resistant to chrysal, very fast growing, readily available and generally about as good for bow wood as anything you will ever run across at any price. I like for people building heart wood bows to make a Mulberry bow before advancing to osage. Since it grows so quickly, mulberry often has large growth rings of up to 3/4 inch though 1/4 inch is much more common.
The wood is almost as yellow as osage, oxidizes in much the same way but turns a little more brown as it ages, is approximately 2/3 the weight of osage, generally. Its wood is usually much easier to work than osage. The bows built from osage and mulberry are virtually identical in dimension and performance. Mulberry is good in a variety of applications for bow building. It is great in composite bows because of its resistance to chrysal, light weight and flexibility.
I have used this wood quite a bit in my bow building. Mulberry has a lot to recommend it, in my opinion.
Dave Goedeken asks:
I saw a guy once who backed his self bow with raw linen. Where
can I buy this product?
Paul Comstock: Try any store or company selling products to textile homecrafters (spinners and weavers). I'm told you can reach one by calling 1-800-USA-WOOL.
New York Filippo asks:
The sinew cable on an Eskimo bow is not glued to the belly, but still works perfectly well. Could one extend this principle and make an all wood composite by tying back to belly instead of gluing it up? And if it works, who has done it? And if it does not, why?
Paul Comstock: The cable works great because it provides a lot of tension without adding a lot of mass to the limbs. Another big plus: the tension can be increased by twisting the cable tighter. Tying a back and belly together would work in the sense that it would shoot an arrow. However, if you tie two 20-pound bows together, you get a 40 pound bow. Glue them together and you'll get a 160 pound bow. Doubling thickness increases strength by 8 times. Which is more efficient? Tim Baker and others have made bows by tying sticks together in a tapered configuration (see Traditional Bowyers Bible Vol. 1).
Halfbreed asks:
Gentlemen, I have made several wooden bows with success . I began by purchasing every back issue of TBM. Should have named my 1st one DEAN . Since then I have read every book I can get my hands on and none informs
beginners how to properly letter a bow . What ink or paint works on various finishes . I use True Oil . I apply a base coat of 3 applications, script on lettering with permanent felt tip and then top coat with 3 additional coats of finish . Looks great for 6 weeks or so, then it fades away.
John Strunk: Yours is a common problem with oil finishes. A varnish such as Varathane Gloss 90 or 900 (available at Ace Hardware Stores) is compatible with lettering on bows. We use Pilot SCA-UF black, extra fine, between the second and third coat with an application of 3-4 coats on top of that. The pen that you are using breaks down because it isn't compatible with an oil finish. We had that problem in the past.
Chris Smith asks:
What exactly is a toothing plane? I've heard multiple mentions of them. They seem to be what I need on composite bows, but I can't find them anywhere.
Dean Torges: A toothing plane is a cabinetmaker's plane with tiny serrated teeth. It does not cut a curl like a regular plane, but instead cuts threads of wood the width of its blade, like excelsior. As a result, it can cut with or against the grain without tearing out chunks of wood, and it also leaves a roughened surface behind, grooved from the teeth, which are about 12 to the inch, ideal as a glue platform.
It's advantage in bow building is that it allows you to flatten surfaces without regard for grain while leaving a lightly roughened surface behind. Such a surface provides great bite for catalyzed glues, assuring the craftsman that clamping pressure will not starve and ruin his glue joint.
They are almost impossible to find anymore, except second hand. I have provided directions for their construction in The Traditional Bowyer's Bible, vol. 1, and cited a source for plane irons. They are not too difficult to build. In addition, Tim Troyer makes them for sale, and if you want to contact me through the GOM site, I will give you his
address.
Jack Smith asks:
I made a bow where the top limb curves in one place more than the bottom. Would backing the bow with sinew help ? If so, how do you do this ?
Murray Gaskins: You are dealing with something we all face and need to be able to handle as a matter of course, without a second thought.
Sinew might help in this situation but more than likely, by the time you repair the hinge in the upper limb, you will probably reduce the bow's poundage pretty substantially. I wouldn't try to learn how to deal with sinew for this early bow because you are going to spend time on the learning curve and about $35.00 to $50.00 on the sinew. Learning to work with sinew is a secondary skill that requires a substantial amount of effort to execute correctly, in its own right, and would not solve the problem that you are currently facing.
My personal advice is to lay that first bow aside for a little while and read a little more about some of the finer points of tillering and solving this sort of problem. If you don't, it will continue as a recurrent theme in your bow building and become the source of much unnecessary aggravation to you. You can get the information you need by reading Dean Torges' new book, "Hunting the Osage Bow", Paul Comstock's "The Bent Stick," or by watching me show you the process on one of my video tapes. Work with another piece of wood if you have one available. You can probably get that bow shooting in less than an hour once you have learned just a little more about tillering. The purpose of this response is not to sell you anything but to guide you around the obstacle you have encountered and get you going as quickly as possible.
Mike "Golfgod" O'Bryan asks:
I have a couple of hickory backings that I would like to turn into tri-laminated bows. I have never tried to make such a bow and am willing to give it a shot. My questions are on mechanical procedures and performance expectations. What can I expect from these bows? Do I need to make a jig for a possible R/D design? Is there a simple inexpensive jig I can make to accomplish this? Any info on constructing these bows will be greatly appreciated.
Murray Gaskins: You will need a form and you might consider making one from a 2x4 by cutting out the shape of the bow you wish to make, belly down, then laying up the hickory laminations on it. I use a piece of truck tire tube next to the 2x4 so the backing can compress into it. This helps with the glue line. Any of several glues is fine, I like Urac, Resorcinol and Smooth on.
As for a 3 lam bow make the form, lay up the first two and glue them together. Taper the center core from full thickness to about 1/16 on the tips. Glue up the belly core. Make sure your moisture is right. Lay up your handle from other 3/16 to 1/4 inch lams going from the fadeouts to as high as you want the handle to be, then work the handle as one piece of wood.
You can tiller the bow on the belly sides and back. I know lots of people who shoot all Hickory composites like this with very good results.
Will Steffen asks:
I've built a few selfbows from hickory. All the bows have string follow. Anywhere from 1.5" to 3". The bows were around 8% mc before tillering. I think that I pushed the tillering process and compressed the wood too much. They shoot great, but I would like to have less set.
What are the ideal steps to tiller a selfbow assuming the mc is in the ideal range? Do different woods respond differently to wood compression ( I'm sure there are differences but if you could explain a little of
what's going on.)
Paul Comstock: For any wooden bow, I would say anything over two inches of string follow causes a significant drop in cast per pound. Different woods respond differently to compression. The easiest way to compensate for
these difference is to vary the design accordingly. Woods weaker in compression will be wider and/or longer than stronger woods.
A few tips to minimize string follow: Don't check the tiller by pulling a brand-new heavy bow long lengths. A very heavy bow can be bent without creating excessive follow as long as it is not bent very far. It is a sound procedure to first tiller the bow as well as possible at brace height distance, using a tillering string and board. After obtaining a wood tiller, you can string the bow. It is my practice, when the well-tillered bow is strung for the first time, to let it sit braced for at least 6 hours before bending it further. This will take care of most of the initial weight loss. Keep in mind how heavy the finished bow should be. If you are shooting for 60 pounds, use a scale and make sure you do not draw the bow past 70 pounds at any time. After every draw, the tiller should be checked to see if a correction is needed. When corrections improve the tiller, the bow can be drawn farther than before because its weight has decreased. If the well-tillered bow is to draw 60 pounds at 27 inches, but it now pulls 70 pounds at 24 inches, reduce the weight slightly and check it again. Don't reach 27 inches of draw until the bow is close to 60 pounds at that length. Check the tiller repeatedly. I would be patient during this process, no matter how long it takes.
Matt Ulberg asks:
Using the Stickbow's posted instructions on the self bow site for all-wood laminated kids' bows, how much of the belly-wood lamination should remain in thickness at the string nocks? I understand that the "quarter-sawn back-lam should be full-depth, but what about the thicker belly lam? Also, how critical are thin glue lines?
Dean Torges: The illustration for the third method of tillering (which involves removing wood from the sides and the belly) show a finished tip dimension of 1/2" wide and 3/8" thick. If the backing is 1/8" thick, the belly wood would be 1/4" thick. However, I have tillered these bows to about 1/2" by 1/4" thick, so that only 1/8" of the belly lamination remains at the tips, with good results.
Glue lines matter more if you attach riser handles than they do between the backing and the belly wood. If you are getting really sloppy mates, if, for example, you cannot clean the mating surfaces after they come off the table saw, it is better to use a catalyzed glue with gap filling properties, like Resorcinol or Urac 185.
Chris Barger asks:
I was wanting to know your opinion on the performance of a hophornbeam bow, and if there were any special guidelines to follow when making a selfbow from this wood?
Paul Comstock: When compared to any other white wood, there are no particular guidelines exclusive to hophornbeam. I once heard a fellow complain that some hophornbeam he had cut checked badly despite all his efforts to prevent it. One answer to prevent this is to split and remove the bark from a test piece to see what happens. Splitting the wood and leaving the bark on for a few months (similar to the traditional method of dealing with osage), or covering the newly exposed back with wood glue or lard are also good bets to prevent checking.
Jeff Collier asks:
I would like to know some measurements, etc. for an Eastern Woodlands bow to shoot and to show to my classes (we do a unit on Native Americans to begin the school year. I have lots of White Ash and Black Locust in the woods out back.
Paul Comstock: Some bow makers want very specific dimensions when "copying" an Indian or aboriginal bow. This approach has some limited research applications for scholars, but I recommend that mainstream bow makers forget about specific dimensions. Among any aboriginal group, the same style of bow will have widely divergent dimensions, based on its intended draw weight, and the size of the person shooting it. If you want to make a 55-pound hunting bow, you could unknowingly copy the dimensions of a bow that was made to pull 30 pounds for a 13-year-old boy. The resulting bow will disappoint you (or at best, mislead you).
Consider the Sudbury bow, perhaps the best known Eastern Indian bow artifact. Everything about the bow suggests it was designed to pull 40-45 pounds. Yet some modern bowyers copy the length and width precisely, and make a bow that pulls 70 pounds. They end up with an inefficient weapon with lots of string follow. I believe the Indian who made it was smart enough to change the measurements if he wanted something heavier. The typical Eastern bow - if placed with one tip on the ground in front of the archer - would be at least as tall as the archer's chin, usually as tall as the archer, and sometimes taller. Most had a rectangular or semi-rectangular cross-section along the length, and bent along the entire length. If you want 55 pounds, shoot for an average width between 1.25 and 1.5 inches. If lighter, go correspondingly narrower. For stylistic nuances (nock shapes, etc.), check the drawings in Bows and Arrows of the Native Americans by Jim Hamm, or the Traditional Bowyers Bible series.
Tom Leemans asks:
Thanks to mother nature, I have some mulberry to use from a blowdown, but there is not quite enough heartwood to build a self bow, so I was going to decrown and back it. What do you think? (I'll try it anyway but wanted an second opinion) P.S., the soil was so wet when it blew down that I don't think the wood was stressed much.
Murray Gaskins: Mulberry makes great bows for about any application or design, from self bows to laminations, and is great for use with a wood backing. You might leave about 1/4 inch of the sapwood on there when you decrown the stave if you don't have very much heartwood to work with. It'll turn out fine.
Ian Priesnall notes:
Two flatbows. One ash, plain stave, single growth ring on the back. One black locust, rawhide backed, bias ringed. Both about 50# @ 28 inch. I'm a target archer, so both bows shoot a relatively large number of arrows.
Both bows looked OK for about 1000 arrows. Then BOTH got chrysals in the lower limb, and BOTH started showing a hinge round the chrysal marks. What on earth am I doing wrong?
Dean Torges: The simple answer is tiller. You are not tillering as well as you think you may be. In this case, too much strain on the lower limb. My guess is that you are tillering stiff tips and the chrysals are appearing mid-limb, shortly after the dips, probably on a flat belly. Correct?
Ian Priestnall follow-up: You are bang on. I was afraid
it was tiller. But developing a good eye on one's own is difficult,
even with all the advice of the Traditional Bowyer's Bible. BTW,
I rescued the black locust/rawhide combo by shaving out under
the chrysals and glueing two shaped facing layers of bamboo on,
then re-tillering. The bow now shoots v. well, but is terribly
dependent on the glue layer (shake tremble!). Very many thanks
for the reply. I'll keep on making shavings.
Mike "Golfgod" O'Bryan asks:
I have a hickory selfbow that I made which is a little stout for me to pull: 78# @27", 64" long. It has zero set when relaxed. My concern is that if I retiller it to around 65# it will be wimpy with set. The reason for this concern is that I've heard and been told that when tillering a bow, it should not be pulled past the desired draw weight , no matter if its at 23" or 29". This bow has been stressed way past the mark of 65#@27". What do ya'll think? Will it still come out right with little string follow?
Murray Gaskins: Your bow will show a little more string follow than it does now, but it should not be enough to affect performance noticeably.
Will Steffen asks:
In "Hunting the Osage Bow," the steamed stave is clamped to a curved caul. In other books I have read, the bow is clamped to a press that reflexes from the handle only. No gentle reflex curve. Which is the best and why?
Dean Torges: Reflexing is done to add cast, and the logistics of bending a bow in the handle to reflex it are simpler than doing it uniformly the length of the stave. I prefer the gentle curve because once the bow is shot in, it will show a profile that is fairly straight. The bow that is bent only in the handle area tends to keep the arrow shelf behind the limbs even when it is drawn. Such bows tend to be too critical for hunting weapons. You are building in an overdraw when you make them this way, with all its attendant problems. Bows made from spliced billets sometimes show this profile. The bowyer attempted to milk extra oomph by reflexing the joint too much, but the cost for extra speed usually comes with hand shock and undue sensitivity.
Eric Bridenbaugh asks:
How can you tell how much arrow length a particular bow will take? I have read that half the bow length or less is good for a self bow, but how far can a sinew backed bow be bent? I am currently working with a sinew backed osage bow of rectangular cross-section that is 46 3/4" long with 2" of reflex. I would like to know what is the longest arrow this bow will take?
Paul Comstock: How far your bow will bend will depend on its width, tiller, the depth of the osage and the depth of the sinew backing. In order for the bow to pull 23 inches, it will almost certainly have to bend evenly along all its length. Sinew bows which pull long lengths typically have sinew totaling up to a third of the limb depth. Whether your bow's reflex would affect draw length would depend on whether the reflex was evenly distributed along the bow. If you want to shoot this bow regularly, my advice is not to draw it more than 40 percent of the length, or about 18.5 inches. Keeping the draw length at 40 percent or less maintains a smooth draw which makes accuracy easier for most shooters. Consider that a 68-inch bow, following the 50-percent rule, should draw 34 inches. I have never heard of any experienced wooden-bow shooter who would attempt such a draw with a 68-inch bow.
Bamboozled in NY (aka Keith Deters) asks:
I have been working under the assumption that in building selfbows, you want to get the limb wood working as soon as possible once leaving the fadeout area. In your TBM series and in HOB, you make mention of "Buchanan Dips". What is the purpose of these dips? Are they just another part of the working limb assigned a fancy name? admittedly, I am not a student of archery history, but I have never heard of these before. Could you give some history on this area of a bow's limb and its significance in the construction of simple self bows?
Dean Torges: The Buchanan dips were named that before there were such things as fadeouts. The dips are like Descartes' pineal gland where mind and matter interact, only in this instance they are where movement begins or ends between the static handle and the dynamic limb. Sorry about the Descartes analogy, but I been wanting to work an allusion to it into a conversation or a correspondence for 40 years now, and just felt time was running out. The difference between fadeouts and dips is that fadeouts are rendered within the body of the riser handle, between
laminations, whereas Buchanan dips are wrought upon the belly itself.
James Duff, in his classic, "Bows and Arrows," noted that only two improvements have taken place upon the English longbow since its birth. One was the take-apart splice and the other was the dip, where the limb and the handle intermingle. He attributed this latter innovation to John Buchanan, a bowyer who, by Duff's estimation, made as fine a longbow as was ever made. The dip made the hard-handled bow possible, allowing bend to distribute through the limbs, but not at all or only very slightly into the handle. In short, the creation of dips allowed for a static handle and less hand shock—a sweeter bow.
Will Steffen asks:
I'm interested in making a hickory backed osage bow. I understand I need to de-crown the osage. Can I use a spokeshave, drawknife and block plane to get the job done, or do I need to run it over a jointer for perfect flatness.
Murray Gaskins: Each of the the tools you have mentioned can have a function in the preparation of the flattened gluing surface on a decrowned stave. My method of approach might be to begin to drawknife the crown to start an initial flat surface and to use either a large block plane, hand held power plane or a joiner to finish the process. I have always been concerned about using a power planer because the finished surface can be compressed and burnished if the blades are not kept sharp.
Incidentally, after using one for years I am not particularly fond of the spoke shave for chasing out or flattening off rings. A better choice for getting the job done is Dean Torges's Bowyer's Edge.
Tony Potter asks:
I purchased an osage stave a few months back and recently finished working the back to a single growth ring. Today I noticed that a small hairline crack has developed in the back. I don't think it is very deep but it runs down a good portion of the bow. Is this stave now destined for the kindling pile or can it still be salvaged?
Dean Torges: As long as the check does not travel to the edge of the bow, no problem. If it concerns you too much, fill it with cyanoacrylate, either HotStuff or Loctite 401. On those occassions when it does resolve in the edge, and especially when it is deep, traveling from the back through to the belly, you are advised to glue the crack with cyanoacrylate and then wrap the area stoutly where it leaves the edge.
Follow-up question by Tony Potter: This is in response
to your e-mail answering the question of the slight
crack in the back of my osage stave and asking for more details.
I purchased this stave under the assumption that it was a seasoned
stave. I couldn't tell you the moisture content or when it was
cut. The stave is worked to a single growth ring on the back
and is two inches wide and two inches thick. The slight crack
starts about seven inches from the top. It runs for about six
to seven inches, then continues in the middle running another
six inches. I first noticed it after leaving it in my car one
afernoon. It doesn't run out of the outline of my stave. Oddly
enough, I'm not sure whether I am imagining this or not, but
it doesn't seem to be as bad now as when I first noticed it.
When I finish this
bow would it be a smart idea to back it with sinew or rawhide
just in case?
Dean Torges: I can assure you that you have nothing to worry about. These cracks happen and do not jeopardize a bow. No need to back with anything, really. And the crack WAS worse after you took it from the car. My guess is that the stave was simply air dried—seasoned, as it were—and not brought artificially below 15 % mc. You placed it in a hot car and forced it to shrink a little too quickly. Ergo, the crack results to relieve tensions. As soon as the stave came to uniform mc again, the crack closed up. Again, if you want to for peace of mind, shoot a little cyanoacrylate into it. Also, you are well advised in the future to avoid cars with osage. Ok with white woods. They are much less temperamental. But osage needs dried more carefully. "Hunting the Osage Bow" details a safe and fast plan for force drying osage.
