Primitive Archer
Main Discussion Area => Around the Campfire => Topic started by: makenzie71 on April 22, 2010, 01:37:00 pm
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I made a thread like this a while back...it got sucked out with the Anything Else/Campfire switch...there were some good suggestions, hope some of you guys voice up again because I can't remember there.
I whipped up a couple of hungarian~ish horsebows...two fiberglass quickies and a bamboo/ipe/ash one. While showing them off I got sucked into a contest...I got to make a bow without using fiberglass, wood, horn, or metal for the limbs. Wood/horn/fiberglass/metal/etc can be used for non-working parts like the handle.
I have no idea what to use lol
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Sinew-backed PVC pipe? ;D
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lol I don't know if we can use sinew.
However...can you get PVC sheeting? Pipe would suck to try and make work, but I do know PVC in general pretty resilient/bendy.
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Some of those plastic rulers are really springy. Is there a minimum size limit?
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Get you one of the plastic 2x4 they sell for decking.. ;D
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Their rules only have a really long list of things you can't use (like horsehair and tobacco) and that it has to be "fully functioning". I want to make something that has at least a 35~45lb draw.
David...I've never dealt with those plastic boards. Are they springy? I might check them out...
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lol I don't know if we can use sinew.
However...can you get PVC sheeting? Pipe would suck to try and make work, but I do know PVC in general pretty resilient/bendy.
Not sure about PVC sheeting but I have seen some 1/8" sheets of lexan for use as window guards. If I recall that's what nalgene water bottles are made of and is supposed to be tough stuff. Sticker said it's 250 times stronger than glass. I'd imagine it would bend with a bit of heat. I'd like to try laminating strips together recurving and bolting onto a solid handle riser. Not sure about tension strength though, wonder if tyvek gives enough for a backing strip?
Kip
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You can buy PVC sheeting, but it's pretty thin stuff. I know they have it in the Home Depot here, it's in the plumbing section.
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I've seen certain kinds of bead board...looks like tile...but it has fiberglass in it.
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I ain't never cut any of the plastic boards thin but in 2x6 it seems stout.. If you like the PVC idea. You could cut a strip out of a thick walled 12" diameter or larger pipe that would be more than enough to get the # you are looking for.. And it would be almost flat..
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I think I've decided...I have a lot of formica strips and I have access to garlock tubing at work. I shaved some garlock down to the rough shape I wanted and glued it up between a couple pieces of formica in my fiberglass magyar mold. Lashed some poplar sayahs on the ends and it pulled and stretched okay but I made the limbs too thin on both axis. Pull was only maybe 15~20lbs, and the limbs want to twist under pressure so I had a hard time drawing it and when it went back the limbs would twist around to basically make the thing "inside out".
I'm going to shave the garlock down into three or four strips and stack them this time, and put two strips side by side to make the thing 2.5" wide at the widest. See how that holds together. Then I'll have to find something else for sayahs...a couple of the other competitors are having fits over it.
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Hello, just a thought, as an old machinist,,, How about using free floating Lexan, similar to the way car rear springs are stacked? poundage could be adjusted by adding or removing "leaves". Also, if I understand the rules, a cable back would help hold everything together,,, Just a thought :) "bowstring"
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One thing to keep in mind for backing is that Gorilla Duc Tape. That is some tough stuff.
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they didn't say nothing about carbon fiber
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they didn't say nothing about carbon fiber
It's implied lol...plus it's a good-natured no prize competition.
I haven't thought about cable bows...that'll make things a bit less complicated.
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didn't some one post a pic of a bow made frome pvc pipe a while back.
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I ain't never cut any of the plastic boards thin but in 2x6 it seems stout.. If you like the PVC idea. You could cut a strip out of a thick walled 12" diameter or larger pipe that would be more than enough to get the # you are looking for.. And it would be almost flat..
it will caust alot to get but a good SDR17 casing pipe will do like the 14 inch is over 1/4 in wall thickness
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been doing some thinking pvc pipe is springy and if you fill the inside with somthing springy maybe you can make a bow like the one that was used in the predator movie when Arnold banded the vines to make a bow
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Perhaps a “panda” type bundle bow made with carbon or fiberglass fishing rod material? That would be a very quick bow to build, and all man-made industrial materials, maybe with that Gorilla tape or duct tape to hold the bundle together.
What about a ballista bow? In TBB V4, Tim Baker shows one, basically a torsion frame the archer holds in the middle and fires as a hand held shooting device.
You could build the spring frame out of some sort of plastic / manmade material, lexan or Plexiglass?, use parachute cord or nylon rope for the springs, plastic washers and tenons locked with plastic pins to twist the rope springs, and use some soft of plastic material for the bow arms.
There is a simple formula for designing catapult spring frames, based on the diameter of the torsion spring. I can post that if it may help you.
Also, maybe use artificial sinew in some way, certainly for the bow string, maybe to even lay courses on the back of a bow, something like a real sinew job.
If you win using my ideas, I get half of the non-prize :)
Dane
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when i was a little kid i thought it would be a good idea to get a pvc pipe, heat it, and flaten it, then use that for the bow. after being heated that much, when cool would it go back to its original springyness and what not?
anyway i want to see this contraption when you get it done. ;D
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The problem with heating PVC is that it turns brittle...I used to use to make intercooler plumbing for my cars. I was reading a post earlier about having PVC with a wooden core...it'd be the same as like a damascus knife: a soft material to add resilience and a hard material for strength. I don't know how it'll work just yet.
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yeah a guy made one of them, but i thought you couldnt use wood? or is it just that you cant use a totally wood bow?
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nah it was just a reference...can't use wood. If I could find something softer than the PVC to use as a core it might work okay.
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nah it was just a reference...can't use wood. If I could find something softer than the PVC to use as a core it might work okay.
How about filling PVC with a foam core either the kind from those pool noodles or perhaps spray foam. I do know that at least some spray foam has adverse reactions with PVC though and melts it.
Kip
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Well... there's always latex tubing, put some rollers on the ends of a frame and attach 2 ends at the handle, wrap around the tips, and meet at the draw point with some string to nock the arrow, use enough strands of that and it'll shoot pretty good, especially you pre-tension the tubing.
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Well... there's always latex tubing, put some rollers on the ends of a frame and attach 2 ends at the handle, wrap around the tips, and meet at the draw point with some string to nock the arrow, use enough strands of that and it'll shoot pretty good, especially you pre-tension the tubing.
that would be cool. kinda like a giant arrow launching slingshot. ;D
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The garlock and formica worked out. 54" bow with lots of reflex. Draws about 35lbs at 28" and it seems to draw forever without any issues.
I'll post pics later this week.
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awsome. :D cant wait to see it.
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sweet if it holds up mite make a good bow firhing bow
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sweet if it holds up mite make a good bow firhing bow
now we could swim accross the river with that tied to us without hurting it. ;D
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indeed it would be a great water bow lol