Primitive Archer
Main Discussion Area => Bows => Topic started by: redhillwoods on January 09, 2018, 02:14:20 pm
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When laminating grips, I have always used belly wood that was at least 3/4", so after tillering there was no stress in the glue line, the piece just acts as a pure riser. As a result, I've never had a grip pop off. I've now got some thinner belly slats so the riser's glue line will be on the same level as the bottom of the belly, creating a potential for it to pop-off. I would like to take some precautions to help ensure that the riser stays on. I was thinking of 1 or 2 wooden stopper pegs inserted in the handle, drilling through the bottom of the riser and terminating mid-belly. Ideas?
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The pegs won't help and could weaken the bow. Make your belly out of enough lams to equal 3/4" and you should be good. Another method that sometimes works is make the riser out of multiple lams of graduated lengths so they can flex some.
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Completely unnecessary. When I make a bow that needs a piece added on for the handle, I add it to the core which is the same thickness as the inner limbs, no pedestal or powerlam, and they never come apart. Good glue, good surface prep, and good design is what ensures a good bond, which will be maintained even if the area flexes a little.
First I mate the pieces as best I can. I'm pretty anal about a good fit. Then groove them with a toothing plane blade, held like a scraper, creating grooves the full depth of the teeth, the length of both surfaces to be glued. Then glue with Smooth On EA 40, clamp, and set a shop light near it for warmth. With the grooves from the toothing plane blade, it's practically impossible to starve the joint of glue.
Now, just because we create a very good joint doesn't mean we should do a lesser job of coordinating the flares and dips, or blending the dips into working limb. Imo, many folks could do a better job of it. So make them flow into one another seemlessly, so from the side you can't tell where one piece stops and the other begins, and so the dips gradually slow the flexing of the limbs. It's the fear of them flexing, and the fear of the handle popping, and perhaps impatience or lack of finess in this area that causes many folks to shape them in such a way that they halt the bend too abruptly, ironically increasing the odds of separation.
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This is about as short and abrupt as I ever make an added on handle piece. The handle block is 9" long, containing a 4" handle and 2.5" dips on either end. I made it this short because the bow was just 58" long, but have made them up to 14" long on longer bows... usually they're about 12". On this bow, the osage and yew lams maintain that 'working' thickness right through the handle/dip area. I cut it out along the line, and then blended it in better when shaping and tillering.
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finished
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Another short trilam with a short added on handle piece... no pedestal or power lam. Of course you can shape the handle other ways and still finess the dips, I know folks who do it with deeper locator grips and shelves cut closer to center, etc.
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Thank-you so much Dances with Squirrels. You put alot of time and effort into that response and I greatly appreciate it. What you wrote makes perfect sense. Thanx for clarifying that for me. And your bows look beautiful.
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This is about as short and abrupt as I ever make an added on handle piece. The handle block is 9" long, containing a 4" handle and 2.5" dips on either end. I made it this short because the bow was just 58" long, but have made them up to 14" long on longer bows... usually they're about 12". On this bow, the osage and yew lams maintain that 'working' thickness right through the handle/dip area. I cut it out along the line, and then blended it in better when shaping and tillering.
I do a very similar build, but add at 1''8 inch (1) lam that extends just shy of the fade.
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Like this.
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This is the way I was taught too.
After glue up of backing to core the shape to fit of the handle is traced out.
A dry fit is done.
Glueing and clamping is done.
Shaping to suit your needs is done next to finish.
This one is about a foot long handle on a 68" bow.Using EA40 smooth on I've never had a handle pop off.
(https://i.imgur.com/CDggXc4.jpg)
(https://i.imgur.com/0mQF9Jv.jpg)
(https://i.imgur.com/8z7bdoq.jpg)
(https://i.imgur.com/Mznxdy2.jpg)
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Deflexed bow are much more unlikely to pop a handle. Straight bows are a different bird.
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That's correct.
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Pearlie,
I agree, but always wondered if it was the return of the limbs right after the shot of a arrow, that caused the separation, not so much the drawing of the bow. I should add vibration, on straight limbed.
Good pics Ed.
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In my opinion, its the way the deflex comes back towards the archer and the straight bow is, well, straight. That abruptness could be why. I see it this way: If I want to cut thin wood I know I can score it and snap it off clean when I use a square edge on my bench. If I tried that same trick on a round edge I probably wouldn't get a clean break at the score.
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Pearlie,
I agree, but always wondered if it was the return of the limbs right after the shot of a arrow, that caused the separation, not so much the drawing of the bow. I should add vibration, on straight limbed.
Good pics Ed.
I've had a few issues on straight bows with handles that popped off. Always during the draw, not the release.
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Pearlie,
I agree, but always wondered if it was the return of the limbs right after the shot of a arrow, that caused the separation, not so much the drawing of the bow. I should add vibration, on straight limbed.
Good pics Ed.
I've had a few issues on straight bows with handles that popped off. Always during the draw, not the release.
I have never had one come off during draw, (that I know of) only after several shots, and at least I noticed it right after a shot.
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If the handle area bends at all the rigid riser will pop off. If you are making a backed bow a power lam is the way to go. With the power lam between the back and belly the handle area won't bend.
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A person has got to realize on my pictures that the core is thinned also from the ends of the fades into the working limb during tillering.Stopping any bending movement into the handle.It all has to be a very gradual thinning.
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If the handle area bends at all the rigid riser will pop off. If you are making a backed bow a power lam is the way to go. With the power lam between the back and belly the handle area won't bend.
The back and belly are already glued together. Seems like a long handle with long fades will disperse the stress enough that everything stays together.
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sorry Bowed I don't know how to use the quotes in the blue box
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sorry Bowed I don't know how to use the quotes in the blue box
Just hit the quote icon and it will automatically go in your post.
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I've done it on bows that are straight from dip to dip, and quite stressed in other aspects of design... narrow, deeply radiused, full recurve profiles in draw weights over 60 lbs... never popped a single one. Prepping and gluing the way I described is less complicated and less work. Some of you guys might want to try it before you discount it... eh, or not.
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I agree with DWS. Old timers used to make bows from thin lams and belly slats that flexed imperceptibly at or near the dips. They got away with it by good prep, not over clamping, and using a suitable glue like a urac or resorscinol(or a proven modern bowmakers epoxy will also do the job properly). When the transition of lams at the dips and handle is marginal, many otherwise fine glues like titebond 3 are too flexible and you will get lifting and separation of the glue line. If the belly slat is thick enough eg 7/8", and a 1/8" backing titebond 3 will work fine.
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How deep are the grooves left by a toothing plane? Just ballpark is fine.
And how wide?
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I did a Google search. I found this vid. https://www.youtube.com/watch?v=7uCmtmj4wsE Do you think this would work? And if so, why not just use a piece of 36 grit sandpaper?
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A hacksaw blade on edge will work as a toothing plane.
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Yeah, for some reason I thought a toothing plane cut little rectangular slots in the wood. I was wrong it appears :)
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36 grit paper is coarse enough to create grooves good enough for "toothing", to increase surface area and to avoid starving the joint from excessive clamping pressure.
A toothing plane will give yo a little more surface area though.
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I've done the hacksaw blade thing, the corner/edge of various files, and 36 grit sandpaper on a sanding block, and they're better than nothing, but they don't leave behind the same quality surface as a properly sharpened toothing plane blade. Others tear, while the toothing plane cuts very cleanly. Does it matter? Maybe, maybe not. It probably depends on how critical the bond is. I feel the joint in my handle and dip area is critical, so I'm going to do it the best way I know how.
When prepping handle gluing surfaces in bows, I don't do the angle/cross hatch technique like he showed in that video, and since the mating surfaces are often deflex and reflex shaped, the blade is held by hand, not mounted in the plane. I hold it more like a cabinet scraper and run it parallel with the length of the work piece. The blade is sharpened on a very slight radius so that it's slightly convex when finished and leaves a slightly concave surface... and I mean slightly... a few thousandths. These techniques make for virtually invisible glue lines along the bow's edges.
If you watch, you can get a toothing plane blade, blade only, on ebay pretty reasonable. The last time, I got a package deal of 4 of them of various teeth per inch. I have 6 of them now ::)
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Yeah, I kind of thought that the cross hatch thing would leave little peaks that would most likely be cracked at the base. Parallel with the grain sounds better.