Primitive Archer
Main Discussion Area => Bows => Topic started by: Mesophilic on June 15, 2018, 09:02:02 pm
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I've had a heck of a time trying to heat bend recurves. Generally the alignment is off and in the process of trying to fix it I only make it worse.
Looking at options I came across Tim Baker's glued on recurve tips in I think TBB 1. It briefly describes tbe method, so I was hoping some of you may have done this. Any pro and con advice to offer? Or pro tips?
Will a normal glue up (roughed up mating surfaces) with epoxy hold, or should I plan to pin or add any other mechanical assistance to the joint?
ETA this would be for a stave bow, either self or sinew backed. Current dims 60 inches by 1.5 inches osage.
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All of the modern basic horsebows are constructed like this but the lap joint is wrapped. Never actually saw a picture of a Baker one with a string on it.
It's better to use a V splice, especially if you are going to sinew.
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"V" splice, I did mine about 3" long. I did a post a while back, I'll see if I can find it.
Found it, hope this helps http://www.primitivearcher.com/smf/index.php/topic,60489.0.html
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Thanks for digging up that thread, DC. Tomorrow I'll take a look and see if I have materials to try to make it work. We're in the process of trying to close on our 1st house so for the foreseeable future funds will be limited. So I'm pretty much suck with what's on hand. I know I have half an osage bow that didn't work out, a block of hickory, some mesquite slats, and a few other odds n ends. The maple grain looks a little screwy but mesquite and hickory are straight, though I'd think a little on the heavy side for this kind of job. I also have some walnut hobby boards about 1/4 inch thick that I could glue up, offset the grain a little, and make a kind of plywood.
The reason Tim's idea grabbed me was that I have an end cut of osage that I can make some ramps to turn into recurved tips and pull off about two inches of recurve.
I'll do some reading up on Siyah construction and and see if what I have might work. It's a little out of my comfort zone, but have to start somewhere if I want to cross an Asiatic horn bow off my bucket list.
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I looked at the bow in TBB you spoke of ,he just used a simple scarf joint for that bow , I thought about doing a shorter stave with that type exstention , there's guys here that did it with the scarf joint that told me they had no issues , I'm going to use smooth on epoxy the stuff is like welded steel ,almost no fail if prepped right !
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The thing that appealed to me about glue on tips is that you can make them up out of offcuts and if one fails you're not throwing away a stave because of it. They do use up some working limb though.
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I have done a bunch of those glue on recurves,sand with 60 grit, mate perfectly and glue, tight bond will do just fine
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Bubby did you use a scarf or a "V" joint?
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Not with the Tim Baker's kind, I'll find a pic and post it
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Here's a pic I found, you can get a nice 1-1/2" flip pretty easy, no pins just glue
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Buddy,
Is that whole section of joint non bending? Acting as a lever? Any braced pics?
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It is only the last 5" of each limb, so that area is generally left stiffish I will look for a brace or FD pic
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This one is not a big reflex but you get my drift
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This was a lonnnng recurve tip. Don't think have pic of tip profile.
(https://i.imgur.com/OVHkFaj.jpg)
(https://i.imgur.com/o3dPTzs.jpg)
(https://i.imgur.com/fvbtkpC.jpg)
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So, Diesel, I have been thinking about this. I think the solution long term lies in getting better at reflexing and recurving your staves. Baker's way works, but so many ways can work.
I've had all the same troubles you have, and I have had bows I JUST couldn't make line up, where after several trips to the forms, etc, I finally broke em. But it can be done.
For me, with my ADHD head, laying good groundwork was the key. Studying staves, squaring and thicknessing them before bending, not trying to fly by the seat of my pants last minute, but having a well made form ready to go when the bow comes out of the boiling pot, etc.
Making a 70 degree recurve 6-7 " long is pretty challenging, but just getting a couple inches of tip "flipped" over 6-8" of limb SHOULD be a cake walk. Also, if you thin the tips enough and plan on adding overlays, etc.. it's gotta work.