Limb Twist Help

[Jim Rocole]

I am having some trouble with my first bow build. Everything went smoothly until now. I believe I may have made an error in the center line of the limbs. when I lay the bow on flat surface with sight window up the upper limb is 3/4" off the surface with lower limb on surface. When I flip the bow over the opposite occurs with the lower limb off the surface and the upper limb touching the surface. After reading the past posts I think I can solve this by sanding the opposite edges from twist to bring them in line and eliminate the twist. Any help would be greatly appreciated. I marked the edge with blue tape that I think I have to sand.


 

 

 

[Mike Most]

Hey I am not the only answer to your question as this site is full of goto guys more qualified than I; here is my take on what I see.  

Since your bow is a take down, have you tried switching the upper and lower limbs on your riser?

Since you built the limbs most probably out of the same form, I wouldnt think it was your limbs but probably the alignment pins being off just a hair.

Does a string run thru the center of your handle when stretched from tip to tip?

I am sure some of the others will chime in shortly.

Regards  

[TradBowyer]

First thing, unstring the bow and look down the bow from tip to tip to ensure they line up. If they aren't lined up, you will need to redrill the pin holes to make them align, If the limbs look good, string the bow, make sure that the string is running down the center of the limbs (manually put the string down the center if you have to). Draw your bow, let down and then look at the limbs. If there is any twist, the string won't track center on the limbs. First thing to do is to make sure your string grooves are perfectly matched in height and depth. If those are good, then you want to sand the opposite side of the limb that the string is laying on. Example, if the string is laying on the left side of limb center, then sand the right side of the limb. Be very careful though. if you sand too much, the limb will twist the other way and at this point, the limb is junk material because it is very difficult to maintain limb stability if this happens. hope this helps

[Jim Rocole]

THanks for the advice. The pin holes are good I used the drilleing jig from Binghams's and have double checked them. Nocks seem right but I will tripple check them. I believe I swapped them at some point and I am kinda of stuck with them because they are already shaped to the riser. I am going to sand the opposite edge sowly and see if I can lay slavage them.

[GREG IN MALAD]

Jim, you could remove the pins from the riser and drill the alignment holes all the way through the limbs, then install the limbs without the pins. Using a string line move the limbs until everything lines up right and drill new pin holes through the limb into the riser. Then use an overlay to cover the holes. I forgot, it helps if you plug the old pin holes in the riser with a dowel before you drill new ones. Using a brad point drill bit helps also.

[Jim Rocole]

Thanks for the idea. I think that is the route I will go with. I have an extra set of limb bolts that I can use.