Author Topic: Recurve twisting  (Read 3405 times)

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Offline PEARL DRUMS

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Re: Recurve twisting
« Reply #15 on: November 04, 2015, 04:19:01 pm »
Just the working portion B-rad.

Many things can make a static do the twist. When the bow lays flat unbraced and the thickness is right on, then the bow wasn't laid out right and you're fighting inner twist, for lack of a better term. String grooves make a big difference. You can deepen the groove on the side opposite the lean and it will pull the tip over more than you might think. If it lays twisted unbraced, well that's an obvious fix. Just have to evaluate and think about the forces at play to make what you see happen.
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 wizardgoat

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Re: Recurve twisting
« Reply #16 on: November 04, 2015, 05:16:42 pm »
I agree with pearly on the belly grooves. All my recurves get them, and they can for sure help in small adjustments. I try to get my recurves perfect at full brace height, I've had recurves that look a little off when unbraced but are fine when braced and drawn

Offline DC

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Re: Recurve twisting
« Reply #17 on: November 04, 2015, 05:30:14 pm »
I read that in TBBsomething, the recurve chapter. A little off at brace is OK as long as full draw is good. I'd like to add the DC version, It doesn't matter what it looks like as long as the string stays on ;) ;) ;)

Offline PatM

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Re: Recurve twisting
« Reply #18 on: November 04, 2015, 08:02:42 pm »
You can also do a tear drop cross section so that a larger loop straddles the recurve and then rests on a string bridge. A string bridge can be better arranged to catch an errant string and guide it back to center.

Offline simson

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Re: Recurve twisting
« Reply #19 on: November 05, 2015, 02:23:07 am »
well, lot of good advice above!
I personally wouldn't take such much wood off on one side so the difference width is seeable. Next time you should heat correct the string alignment before doing only subtle scrapings on one or the other side of the limb. By the way side corrections with scraping on one limb side is a good thing on D-bows, but on recurves it is much more complicated. It belongs a lot where you scrape (mid limb or outer limb, or hardest thing at the lever).

Back to your problem/bow:
Clamp your bow in the vice at handle. Crap the lever and pull it in right position while watching what the limb does. There should be a portion where it wants to break out, scrape here! Hope that makes sense, always hard for me German to explain in English.
Simon
Bavaria, Germany

Offline DC

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Re: Recurve twisting
« Reply #20 on: November 08, 2015, 12:39:22 am »
Well I've been heating and bending this thing every day and I just can't get it just right. I got it close once. I was looking at my older R/D today and noticed that the limbs on it are quite a bit wider. On this one the limbs are 3/4" wide and 3/8" thick right where the recurve stars and they are 1 1/4" at the fades. Is it possible that they are too narrow and that's making it throw the string? It has about 4" of reflex and deflex. The tips are even with the handle. Just noticed that.