Limb twist question. FIRST BOW!

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Limb twist question. FIRST BOW!

Postby Stephenamertes » Wed Feb 03, 2016 10:21 pm

So I was hoping to get some advice from some of the many knowledgeable members here such as Greywolf.

This is my first laminated recurve and I recently got it all glued up and knocked off all the epoxy. When putting it on a simple tiller stick I noticed a fair amount of twist on both limbs pointing in the same direction(I guess my mold wasn't perfect, oh well). I noticed that the twist is corrected if I move the "nocking point" further in the opposite direction of the twist which naturally also offsets the centerline through the riser.

My concern is that with a recurve that is only 1 3/8 wide, if I offset the centerline, my bow will be super narrow. Like barely even 1 1/4. Is there a way I can keep the centerline in the current physical center, but still take care of the twists? Can I take material off of the side opposite from the twist(the strong side)?

I hope that made sense. The whole limb twist thing is confusing to me. I can work on some pictures as well.

Thanks a lot!
-Steve
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Re: Limb twist question. FIRST BOW!

Postby stickandlimb » Tue Feb 09, 2016 7:25 pm

need more info....like what is it laminated with ...? Bamboo ?.........Is this a glue up that was wrapped up with inter-tube ? A picture would be nice...........spraying the bow with cooking oil.....putting it in a vise at the handle .......putting a pipe wrench on the tip leaning the direction it need to go and applying heat from a blow drier or heat gun can take out the twist ......but to much heat will weaken the glue......Over twist it a little bit because after you take off the wrench .....( After it cools off for an hour )........it will spring back a little.....Hope this helps....
Its all mind over matter..If you don't mind it don't matter.......
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Re: Limb twist question. FIRST BOW!

Postby Stephenamertes » Sat Feb 13, 2016 11:57 am

Thanks for the reply!

The lams are walnut with .05" of glass from binghams. I think it was user error due to my press not being perfectly square. My glue lines are good tho.

I ended up fixing it by taking material off and offsetting the centerline slightly. I now have the limbs shaped and nocks on with it tracking straight with a long tiller string.

My most recent issue is that I ended up gluing an extra .03" strip of glass on the belly between the wood and the main glass which has made .08 of glass on the belly! I did this originally with the hopes to make up some lost weight due to my narrow limb width.

Well it is pulling at 85# at 28 which is way more than I want...lol! I wanted it closer to 60#.

Since I have .08 of glass on my belly, can I flat sand .02 or .03 off the belly being careful preventing tiller issues? I figure I could take off 20+ lbs just by doing that. And what would be the best way? Using a sanding block?.

I know that rounding the corners and finish sanding will help too.

Pictures are coming up

Thank you!
-Steve
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Re: Limb twist question. FIRST BOW!

Postby Stephenamertes » Sat Feb 13, 2016 12:26 pm

for whatever reason when i try to upload a picture it just loads a blank page. any suggestions on the easiest way to get a pic on here?
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Re: Limb twist question. FIRST BOW!

Postby stickandlimb » Sun Feb 14, 2016 10:33 am

Greywolf would be the man to answer that one...........
Its all mind over matter..If you don't mind it don't matter.......
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Re: Limb twist question. FIRST BOW!

Postby Stephenamertes » Sun Feb 14, 2016 1:58 pm

He has been helping me out. I just figured I would see what others thought. Since I glued two glass lams together, I think I was inadvertently asking for strange results. In theory, I would think I could drop a good amount of weight by sanding .02 or .03" of glass off the belly since I have .08" of glass to work with on the belly.
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