Laminate recipe help needed

[glenbo]

I am in need of some advice for making a straight limbed longbow. I was planning on going 68" long with an eighteen inch riser, 1-1/4" wide at the fades tapering to 1/2" tips. I would be using black glass on the back and belly . I am looking for 50 lbs at 28". Can someone  recommend a lam recipe that will get me close?
 I have built only one lam bow before. I called Kenny M with my needs and it worked out great. I am not sure of the thicknesses I used. Can anyone recommend a supplier? Thank you, Glen

[rmorris]

Big Jim can get ya everything you need in one stop since you are using black glass. I use a total stack of .440 with .05 glass. I also use a .oo5 or .006 total taper with a 16" riser. This get me at 50# @ 28" for the bow you described

[Magnum in Ms]

That sounds very close to Bingham's 68" straight limb bow. They have a chart on their web page.

[jhk1]

Does the total stack measurement of .440" include the .100" (2 x .050") of glass?  I assume "yes", but just want to confirm.
Thanks.

[monterey]

Originally posted by Magnum in Ms:
That sounds very close to Bingham's 68" straight limb bow. They have a chart on their web page.

It is except for the width at the fades.  The Bingham is held as close as possible to a full 1.5" and the tips are narrower than the 1/2".

You can still use the Bingham chart by reducing draw weight by a linear amount for the 1/4" reduction.  If you go with the bingham stack of .404 for a 55#, the 1/4" reduction will get you to 50#, but you will want to reduce the limb tip width or increase your lam tapers somewhat.  That will change things a bit but not sure what to predict!

You could simply go ahead and build the Bingham bow.

[monterey]

Originally posted by jhk1:
Does the total stack measurement of .440" include the .100" (2 x .050") of glass?  I assume "yes", but just want to confirm.
Thanks.

Note that he is using a 16" riser, which is not a bad idea at all.

[rmorris]

Yes, the thickness of the glass is included in the total stack, I also measure my total stack just after the fade outs.

[glenbo]

Thanks Guys. I appreciate the help.

[kennym]

Glenn, do you remember approximately when you did the other bow? I tried to look it up but didn't find it.

I would go with .004 total taper and about .430 stack with .050 glass included, wild guess!

Or go with rmorris' stack, he obviously builds these!  :D

[glenbo]

I believe it was last summer Ken. The bow turned out nicely and has helped me take two bucks last fall. Looking to build a back up.  Thank you to all . Glen

[kennym]

Let me look again tonite, I will have it....

[JamesV]

Why can't you just measure the bow you already have to get the stack for a back-up bow? I do that all the time to copy an existing bow and it works good for me.

James

[kennym]

Hi Glenn, here is what we had -- .370 total with .002 taper for a 66" bow  50@ 28" with .040 glass both sides.

Don't know riser length....

I don't know if it was 1.25" wide either...

If it was and you like the way it bends, I'd go with same deal, but around .400 total stack(you can lose a couple # pretty easy , but can't put it on)

[glenbo]

Thank you very much Ken. I truly appreciate your help.  Glen