trapping a glass bow

[fujimo]

so for folk who have trapped glass bows, how much can a person trap a bow.
made a fubar on a stack calculation- a 45# bow came out at 58#   :eek:    
down to 52 # now- maybe trapped 1/8 right now
narrowed bow to 1.4"

any thoughts?
 my concerns are trapping too much, and possibly creating some limb stability issues.

[mwosborn]

Longbow?  I have trapped quite a bit on a too heavy longbow, but 58 to 45 is a long way!

[mwosborn]

Also, is the glass .04 or .05?  you can sand quite a bit off the limbs too - especially if they were .05.

I have a have finished 59# recurve hanging in my shop.  I missed the stack on that one.

How wide are your tips right before the overlays???  Looks more or less like you got a 50# Bow...

[kennym]

Probably depends on how much D/R is in it. Hill bows can be very narrow. The reflex is where you will have probs methinks.

Mitch has a good point on glass thickness, tho I hate doing that personally.

Rich also has a point on the tip width. You can go 1/2" easy with no probs and wonder if you lammed a couple extra glass pcs like 3-4-5 " on under the overlays if you could go narrower?

 
Might be a rocket launcher!

Disclaimer: I haven't done it....

[TradBowyer]

i trap my longbows about 30% and I lose about 10# if I remember right. Much more than that and you risk developing twist plus the aesthetics aren't the greatest. 10# is about the max that I will do on mine

[fujimo]

its a 64" kenny m longbow
problem is when working with yew lams- one needs to add a % to the stack.
i ended up adding the % twice    :D    
we have it down to 52 right now-
tips are 1/2 " wide
.040 glass.
 so maybe with a wee bit more trapping- 15% each side-  we could get it down to 48- that would be awesome!!

Try narrowing your limbs a little more...  I generally like going just under a 1/2" at my tips...  Then round the glass a little at the edges and see where that gets you...  Also see where your bow is bending...  You might want to sand some glass to get it bending optimally...  Do you have some pics at brace and full draw??  Like Kenny said if this pans out you may have a rocket launcher...

[TradBowyer]

I'm just throwing this out there but just because you thin the glass doesn't mean you'll increase speed. when you want the glass you are changing the ratio of wood to glass which can actually have negative effects.standard rules of thumb are 040 for up to 60# and 050 for 60 and up.