Author Topic: Help designing recurve  (Read 2360 times)

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Offline FilipT

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Help designing recurve
« on: April 14, 2017, 06:42:56 am »
I am more of a flatbow maker, my bows are usually 66" NTN and above and non recurved. Could you guys help me with few things so I can make my first self bow recurve also a bit shorter than I usually make?

I would use European ash for it, aiming for 50# at whatever draw.

1. My usual draw weight is around 28", but I am willing to go below that. I see you guys like shorter draw weights for your shorter bows.
What is the minimum length NTN I could go with 28" draw, or what NTN length you would prefer for draw lengths under 28"?

2. What is best method for making curves on European ash? Dry heat or steam?

3. In what stage of tillering should I introduce curved tips?

4. What profile of limbs and width I should look for? Also what thickness would give me enough wood for tillering?

Thanks in advance

Offline Pat B

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Re: Help designing recurve
« Reply #1 on: April 14, 2017, 07:55:28 am »
You should be able to go 62" to 64" for a 28" draw and 50# is not out of the question.
 For the recurves I think steam would be best.
Make your limbs parallel or with a slight taper full length to start with. Get the bow bending well and be sure the string tracks well at low brace then shape and bend the tips. I think 2" wide at the fades would work fine then about 1 3/4" where the tips narrow. If you find the limbs getting too thin reduce the width a bit.
 If you are using a board keep it full thickness and tiller down from there. I'd do about the same with a stave.
Make the most of all that comes and the least of all that goes!    Pat Brennan  Brevard, NC

Offline upstatenybowyer

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Re: Help designing recurve
« Reply #2 on: April 14, 2017, 08:46:27 am »
Pat pretty much covered it. I would add that you need the wood to be a just a little thicker where there the recurves are, which is another advantage of waiting to steam them in until you've got it tillered out to about 20" or so. Just don't touch the last 5" until that point. Leave the tips at least an inch wide until the recurves are set. That will help with bending them and string tracking when you're close to finished.
"Even as the archer loves the arrow that flies, so too he loves the bow that remains constant in his hands."

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Offline Del the cat

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Re: Help designing recurve
« Reply #3 on: April 14, 2017, 12:09:20 pm »
I'd say if you are producing a more highly stressed design by adding recurves, don't make it shorter. Always better to change one aspect at a time.
And don't be too heavy handed with the recurve. A gentle recurve that succeeds is better than a big one that pulls out.
Del
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Offline PEARL DRUMS

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Re: Help designing recurve
« Reply #4 on: April 14, 2017, 12:20:47 pm »
Build the same bow you describe as your normal style. Use steam to bend the recurves in, usually 30 minutes of steam time is enough. No reason to change your design. A recurve is nothing but a flat bow with the tips recurved.
Only when the last tree has died and the last river has been poisoned and the last fish has been caught will we realize we cannot eat money.

Offline FilipT

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Re: Help designing recurve
« Reply #5 on: April 14, 2017, 12:35:48 pm »
I have seen osage 54" recurves on this forum. Is that possible just because its osage? Shouldn't that be extremely stressed design as its very short bow with recurves?

Offline PEARL DRUMS

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Re: Help designing recurve
« Reply #6 on: April 14, 2017, 12:55:11 pm »
If you stick with draw length multiplied by two plus a 10" grip/fade area you will have a solid, smooth bow when you're done.
Only when the last tree has died and the last river has been poisoned and the last fish has been caught will we realize we cannot eat money.

Offline bubby

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Re: Help designing recurve
« Reply #7 on: April 14, 2017, 01:18:24 pm »
The shorter you go the more set you will likely end up with so it's a trade off, i dont have any experience with ash but with osage you will be pretty safe set wise at 62" ttt
failure is an option, everyone fails, it's how you handle it that matters.
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Offline FilipT

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Re: Help designing recurve
« Reply #8 on: April 14, 2017, 02:34:40 pm »
I currently have only ash to work with. There is no osage in europe nor I have money to buy one from the dealer and ship it here.

Offline FilipT

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Re: Help designing recurve
« Reply #9 on: April 17, 2017, 07:45:11 am »
So I should leave at least 1" wide tips before I make recurves and later I narrow them to what they are supposed to be? But what about thickness?
How do I tiller till 20" (or something like that); do I leave last couple of inches alone and tiller until that point and leave these tips thicker? What should minimal thickness of recurved tips be?

Offline Pat B

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Re: Help designing recurve
« Reply #10 on: April 17, 2017, 08:36:08 am »
Leave the last 5" to 6" thick (1/2" to 5/8") while you tiller the limbs. I'd also leave the handle area untouched until after tillering. You don't need either area finished until later anyway and by leaving the handle blocky you have a place to clamp the bow while working on it.
Make the most of all that comes and the least of all that goes!    Pat Brennan  Brevard, NC

Offline PatM

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Re: Help designing recurve
« Reply #11 on: April 17, 2017, 08:48:18 am »
I currently have only ash to work with. There is no osage in europe nor I have money to buy one from the dealer and ship it here.

Osage is actually grown over there.

Offline FilipT

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Re: Help designing recurve
« Reply #12 on: April 17, 2017, 10:02:44 am »
In Croatia it was planted by Austro Hungarian empire only in parks. You cannot cut trees from parks and also these parks with osages are in capital of Croatia, not where I live.
Only place where osage grows by itself is Hungary and Carpathian basin.

@Pat B
Does this tickness comes off in last stage of tillering when I put recurves or do I leave it like that even when bow is finished? I know about handle, I always leave it blocky, otherwise I couldn't put hold the bow in my tiller tree.

Offline Strichev

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Re: Help designing recurve
« Reply #13 on: April 18, 2017, 02:11:31 pm »
Hey, Stalker, did ya see any Laburnum around you? I hear it grows in Slovenia but haven't seen any yet.  Supposedly the partisans used it as fire fuel during the war as it's said to produce less smoke when burning. Sounds like a myth to me.

Anyway, ash is great, in flatbow configuration it should me superb. Keep it really dry, I read that it needs to be dry but now, after working with it some more, I see it needs to be really dry.

But yeah, Osage is rather exotic around these parts. Make sure to keep us posted on the build, I have an ELB in the works now but after that I might try a recurve. Gonna learn from you. :)

Offline FilipT

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Re: Help designing recurve
« Reply #14 on: April 18, 2017, 04:57:03 pm »
Laburnum? Its called "zlatna kiša" here (eng: golden rain), I saw it once in one park in my city and that's it. It was a bush with 1" diameter branches. Not sure where you can see it in the wild, although I saw on internet pictures of beautiful bows made of it.

I heard that thing about ash needing to be super dry, supposedly it really likes to soak in humidity. I will keep all posted on build, but this will not be in some time.
I am making two swords and they are priority now.