Author Topic: Fixing Limb Twist - Help Needed  (Read 2130 times)

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Offline willie

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Re: Fixing Limb Twist - Help Needed
« Reply #15 on: April 07, 2020, 04:19:44 pm »
Pat, I mention it as something for the Mark to consider. Red Oak can have excessive soft earlywood, Its location and orientation could be a factor. Even with diffuse porous woods, I notice areas that are softer and harder when scraping.

Offline mmattockx

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Re: Fixing Limb Twist - Help Needed
« Reply #16 on: April 07, 2020, 04:25:09 pm »
Be sure thickness is even and then heatgun and twist. I made two bows from neighboring parts of a thick board and both had the same tendency to twist when braced, each limb in the opposite way. The first one I screwed by trying to adjust thickness - did not work at all and the bow finished light - the last I heated and twisted and it is all good.

This seems to be exactly what I have here. I will clean up the limbs to even and then see about twisting them opposite to the way they want to move.


Some wood apparently has stress in it and will twist when strung, all the scraping in the world won't untwist it. I always use taper lines on my bows so I know the sides are even, when on of my  bows twists when strung I don't waste time scraping on the strong side, I get out my heat gun.

So do you twist it past center in the opposite direction to the way the limb wants to go, sort of preloading it to pull straight when drawn?


What kind of twist is it? Propellor? All one way?
Was it there  when you started (natural)?
Jawge

It is propeller twist, the nocks go in opposite directions. The board was straight when I bought it and warped in one direction after acclimating to my shop humidity levels (looked like reflex after I glued the handle on) but no twist. It still has no twist when sitting unloaded, the nocks move as the bow is drawn.


not if the cause of the twist was a variation of density in the limb.

It doesn't seem to be the case since both nocks move in opposite directions more like propeller, but there certainly is significant variations in density through the early and late wood rings.


Thanks to all for the help, at least I know I'm not alone and this is a fairly common occurrence. I will try twisting with some heat and see if I can get it to level off.


Mark

Offline willie

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Re: Fixing Limb Twist - Help Needed
« Reply #17 on: April 08, 2020, 12:10:47 pm »

Quote
So do you twist it past center in the opposite direction to the way the limb wants to go, sort of preloading it to pull straight when drawn?

Sometimes limb twist doesn't seem to affect shooting. If you choose to correct, I would try to minimize any torquing apparent in the hand on the draw. Even propeller twist may not create torque.