First glass bow with a twist.

[Nicon]

Heynow! My name is Gert and i'm a newbie bowyer from Estonia.
This is my first bow in 6-7 years and my first glass RD.

It was planned as a  68" 40#-ish @ 28" RD for target shooting. It has a slight glued in twist in it. My form was uneven...
Can a glued in twist be fixed, or will it be ok with the twist in? I tried removing material from the stronger side. I removed quite alot becaus it was also a little bit on the heavy side, but it had no effect. Also tried heating and twisting. After heatit had a little oposite twist in it, but the old twist came back after stringing it.
 
I hope i don't have to scrap it. Materials here in Estonia are crazy expensive! Quart of smooth-on ea 40 was 100$...

Also a question about measuring arrow spine. Do i measure the stiff side and use that measurement to select the shafts?

[2treks]

Show us a picture of the bow un-braced please. Back side up and sighted from tip to tip.
And maybe a picture of the side with string on.
Stiff side of arrow is correct, And,

WELCOME to Tradgang!

[Dale in Pa]

Gert, You need to remove material off of the right side of limb tips as it's pictured. on both limbs to bring the string to the center and then cut nock grooves deeper on R sides.

[Trux Turning]

Based off the picture- deepen the string nock on the right side starting with the closest limb in the picture (you may have to do the same to the far end too) once the string is tracking remove the excess material near the tip.

[Nicon]

Hey! Thanks for the replies.
I deepened both nocks about 0,05". String is now centered on the riser, but the twist hasn't changed. How much along the limb should i remove? My taper starts at the riser fades. Should i remove the excess also from the fades to keep the main taper equal?
I read that you should remove material from the opposite/stronger side that the limb is pointing/twisting. If i remove material from the side that i deepened the nocks, wouldn't it be the opposite and make the twist worse? Or is it different when the twist is glued in because of the funky form?

These pictures were taken before deepening the nocks. But they would look pretty much the same so i guess it doesn't mater much.
 
 

[Dale in Pa]

Grind the last 8 or 10 inches near the tips on the sides where you deepened the nocks. Then just eye ball the limbs for proper alignment and adjust if needed.

[Nicon]

Just a little update. Been busy at work and haven't had much time to work on it.
Got rid of most of the twist. I still have remove 0,2" from the riser to get the string running in the center. I want to cut the sight window so it's center shot. I remember reading, that it's more forgiving for the arrow spine. I want to make boo arrows and i can't get them in right spine. Even thin shafts are way over the spine for the bow.

Right now it's pulling 35#@28" Pretty much on the money.
Also forgot to mention that it's maple limbs with red oak riser.

How does the tiller look?

 
 

[GREG IN MALAD]

Gert,
Just a couple random thoughts. In the first photo it looks like the centerline of the bow is crooked. I dont see much twist but the bow sure looks like it bends sideways. How did you mark the centerline? Check out this thread for help removing limb twist, the diagram in the first post is correct.  http://tradgang.com/noncgi/ultimatebb.php?ubb=get_topic;f=125;t=007714#000000

The tiller looks good so far but on the next bow I would recommend using more thickness taper, that will get the middle of the limb bending more.
For a 35# bow I would recommend center cutting the riser, like you said, most arrows will be too stiff if you dont.
Looking good so far.

[Nicon]

Oh joy! I messed up again...
The bow wouldn't fit under my ghetto engineered   jigsaw jig  so i used a puny hack saw and cut the sight window way too deep.
 
Arrow runs right in the center now, but the wall is too thin. It's 0,43"x2,24" at the base of the window.  It feels a bit bendy to the sides. Accident waiting to happen? I was thinking of gluing some veneers to the other side for reinforcement and some added color action.  It's not going to be a pretty bow anyway...

On this one i used only one tapered lam with a 0,001" per 1" taper. I have few of these full length lams left. For the next i'll use a 0,002 or 0,003. But first i need to build a lam grinder and clone the tapered limbs for future  grinding guides.

[arrowlauncherdj]

Oooh, that is a bit too thin for my taste even at 35 lbs. pull. Perhaps if you took some glass and left over wood lam pieces and made a sandwich out of them... like this: glass, then thick piece of parallel lam, then glass, then lam, then glass again... then put a couple pieces of extra material on the back of the bow (back meaning the part of the riser facing away from you)... It would strengthen it a lot, then you could use that extra material to blend with the riser using your sander and have a nice deep thumb groove.  It would almost look like actionwood.  

The length of the overlays on the side and back of the bow should go a minimum of top of the sight window to bottom of grip when you start, that way when you blend it into the riser shape, you dont lose the strength of the glue joint.  Hey it might look pretty cool when you're done, never know.

Dave

[arrowlauncherdj]

Oh, and use a .002 taper on the next one, not the .003 if you asked me... based on your photos of the draw cycle above.

dave