Author Topic: First composite bow  (Read 4768 times)

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Offline DCM

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First composite bow
« on: January 04, 2022, 03:44:35 pm »
Long time listener, first time caller.  I kept googling strange information about bow making, and this place kept popping up.  I have been working on a horn bow, after making a couple wooden ones I decided to try my hand at a composite.  It's water buffalo and hickory.  Why I backed with hickory, I couldn't say.  It seemed like a good idea at the time, based on available materials.  I had a good quality hickory stave and was reluctant to use bamboo on this, so here we are.  I put the core and belly together with liquid hide glue, which I now regret, but I'm not going to reverse course at this point unless it delaminates.  I will say this though.  I have a lot of faith in my glue-up.  :)


The siyahs are purple heart, walnut, hickory, and paduk.  I am thankful that the laminating went as well as it did.  I think using 20 clamps helped with this as well.  They are still a little blocky and will need some slimming down.

I experimented with some granular hide glue until I figured out the basics.  Then learned about gram strength and had to order more.  I was experimenting with 192g, but waited to put the siyahs on until the 444g came.  It kept turning into gelatin as I was trying to attach it.  So after several attempts, I added more water, upped the temp of the glue to 141, then used a head gun on low on the bow tip and siyah.  I figure if it pre-heating my coffee mug works, it'll probably work for this.  And it was pretty satisfactory.

I let it sit for three days, for paranoia's sake, before taking the clamps off.  It's been cold and wet here lately and this far in, I'm being cautious.  The siyahs are shorter than I had envisioned, and the angle not as extreme.  I'm beginning to think that's probably for the best though, since I'm not really sure how the thing will work out.

Initially I was going to grind the siyah off at the red line, putting a string pad at the green arrow.  Now I may be off in my concept of the siyah, but would performance be improved slightly if I kept my rasp to myself and placed the pad at the blue arrow?

And here's a pic of the whole thing today after coming out of the clamps.  The handle is hickory, and due to maybe inexperience and wanting to avoid a critical failure, it has a hickory slat on the belly side as well.  I have a fair sized hand, but it still feels a little blocky in the back, especially to my thumb.  I'm going to have to thin that out, even though it makes me nervous.  Then deer backstrap sinew on the limbs, then the handle.  And then I will have to grapple with how I want to wrap the thing.  I tried birch bark on my mini-mongolian bow and am not really pleased with how it's going.  I may have to make a leather sleeve for it.

Any advice is very welcome!  Thanks
« Last Edit: January 04, 2022, 03:49:53 pm by DCM »

Offline WhistlingBadger

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Re: First composite bow
« Reply #1 on: January 04, 2022, 06:34:19 pm »
Welcome to the forum.  Interesting looking bow!  I'm going to have to look into siyahs, since it might work for something weird that I have in mind...Looking forward to seeing how this beast turns out.
Thomas
Lander, Wyoming
"The trail is the thing, not the end of the trail.
Travel too fast, and you miss all you are traveling for."
~Louis L'Amour

bownarra

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Re: First composite bow
« Reply #2 on: January 05, 2022, 01:50:39 am »
Welcome and well done for having a go at a composite.
Yes the tips are too big. Width 12mm and thickness 15mm at the tip. Really your tips should've been v-spliced into the working limbs. Your method may work but for future reference the v-splice is the way to go. Better to use lower density woods for the tips. My choice is hard maple.
Making your own collagen based glue is easy enough.
When using collegen based glues you need to pre-heat your parts and also size the parts very well before attempting to glue-up with many (15+) coats of 5%  (thin) glue. do this until the surfaces are glossy before adding the thicker glue at glue-up.
You don't need so many clamps!

Offline DCM

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Re: First composite bow
« Reply #3 on: January 05, 2022, 05:18:33 pm »
Thanks.  I narrowed them out significantly here, and they come down to about 3/8's at the tip.  I will try to remove more when I sand them down to their final form.  I really want to make the next one out of walnut.  Assuming I start thinner in the first place, is there anything objectionable about using walnut for the siyahs?

My sizing coats were gradually turning into a mound of gelatin, and I didn't really know what to do with it.  Hoping that it turned out okay.

Badda bing, badda clamp. :)

Offline superdav95

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Re: First composite bow
« Reply #4 on: January 06, 2022, 04:42:40 pm »
Well thatís neat.  Itís similar to the one Iím working on at the moment.  As for your syahs I used iron wood for mine and maple in the past mostly.  As mentioned already less mass is better on the tips.  This has been my experience too experimenting with different wood for syahs.  Best of luck on this project and welcome to the forum! 
Sticks and stones and other poky stabby things.

superdav95@gmail.com

Offline DCM

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Re: First composite bow
« Reply #5 on: January 13, 2022, 07:24:19 pm »
Hey thanks for the warm welcome.  I have removed a lot more mass from the siyahs, I'd venture they're half what they were at the start.  Still pretty dense wood though.  Reduced the handle and rounded the core a bit, it actually kid a feels like a bow in the hand now.  Gonna start processing sinew.

I really want to reflex this at least a little bit, but it makes me nervous as I've not done it before.  Thinking I will dabble and just reflex a couple inches to see how it goes.

Offline superdav95

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Re: First composite bow
« Reply #6 on: January 15, 2022, 01:36:00 pm »
its a nice look.  I would go thinner yet I think.  just my opinion.  keep us posted

cheers
Sticks and stones and other poky stabby things.

superdav95@gmail.com