Laminated glass longbow- parallel vs. Tapered lams

[arachnid]

Hi guys.

I was wondering, is there a difference in performance between 2 bows, one with tapered wood lams and the other with parallel wood lams. And if so, is it so significant?

Here's the thing- I don't have a thickness sander and the only option for me is to taper with a hand plane. So I thought, maybe it's better to just use parallel lams rather then have an uneven taper.

And one more question- is there a benefit in using 3 wood lams instead of 2?

What do you guys think?

[monterey]

Taking your last question first, will this be a glass/wood or all wood?

Another question is what will be the configuration of the "Longbow"?  Will it be an ASL or an R/D bow.

You could build a pyramid style bow with parallel lams in glass/wood or all wood.  It's a design that lends itself to limbs without thickness taper.

[arachnid]

Oh sorry, I guess I didn`t mention the important stuff.

I want to make a R/D longbow (A 3 pc takedown, limbs using KennyM`s form), glass and wood laminated.

I didn`t think of a pyramid design.... I`ve built pyramid bows out of wood (selfbows and wood-lams bows)... never thought of that design for a R/D glass lam bow....

Your thought`s plz...

[monterey]

I don't have any idea what to expect from a pyramid KennyM bow.  Maybe he will comment.

I think you will want some taper though.

[Mad Max]

I made a 62" Recurve, Parallel width on the limbs (1-5/8" wide).003 total stack taper.

I made it with .002 total stack taper.
Now the limbs width have to be tapered.
I like the way it turned out.

narrow limbs have better performance

KennyM's bow is .003 total stack taper and it's 1.45 wide at the fades and 1/2" at the nocks.
I would  think you would have to go wider at the fades to get it bending right.

[kennym]

Yes, like Mark said, It would have to be real wide at fades to keep the reflex from being too much. You have to have taper somewhere for a limb to bend right on a D/R bow. Parallels only would make a lot of bend at the fades. IMO

[monterey]

If you are set on no taper you could go with a 1.75" to 2" true pyramid with very narrow tips.  Maybe a power lam and a tip wedge. That's a lot of width at the fades but it disappears quickly with narrow tips.  The width will not be contributing weight where you don't want it and will provide protection for the fades.

                       DISCLAIMER!

I've only built these with boards so the above is Swagging and speculation

[arachnid]

Thanks for the input guys.
Now,I guess I'll need some help in the design here so bare with me.

If I do have to taper the thickness by hand, I rather make 2 wood lams in each limb, one parallel and one tapered. I already have maple lams cut to 3mm thick.
The only glass I can get at an affordable price, is "bearpaw powerglass", 38mm wide and 1mm thick.

My plan is to build a takedown longbow, limbs using Kenny's form (Thanks for tat Kenny), my target weight is 40#-45#@26". I'll start at 66" long so if it turns out lighter I can shorten it.

My main concern is the limb stack... Since I only built wooden bows until now, I have little idea where to start... So if you can point me to a good start it'll great.

Again- 2 maple lam, 3mm thick each+2 glass lams, 1mm thick each.

Thanks..

[Mad Max]

How much would the shipping cost for the lams if we did them in the USA????

[arachnid]

I live in Israel. I checked both 3River's and Bingham. The cost of 1 bo-tuff is about 20$. When converted to ILS it's in the 90ILS area. That's ALOT for 1 strip. Not to mention the high shipping cost.

The only affordable option for me is to order from a guy on *****. That's why my option for fiberglass lams are very limited... I have to do with what I have...

So I really need some directions.

[jhk1]

You may be able to get some advice/guidance from Kegan McCabe at Omega Longbows.  I've got one of his earlier Omega Original longbows (it's a somewhat aggressive R/D design.  I got mine second-hand; I think it was built 4-5 years ago), and it looks to me like it has parallel lams (2 maple lams, no thickness tapering).  All of the tillering seems to be accomplished by the limb width tapering.

I also had one of Kegan's earlier Omega Imperial longbows (again, got it second-hand. 68" length, 45#@31") that was constructed with a single hickory lam that appeared to be parallel (no thickness taper).

[arachnid]

Originally posted by jhk1:
You may be able to get some advice/guidance from Kegan McCabe at Omega Longbows.  I've got one of his earlier Omega Original longbows (it's a somewhat aggressive R/D design.  I got mine second-hand; I think it was built 4-5 years ago), and it looks to me like it has parallel lams (2 maple lams, no thickness tapering).  All of the tillering seems to be accomplished by the limb width tapering.

I also had one of Kegan's earlier Omega Imperial longbows (again, got it second-hand. 68" length, 45#@31") that was constructed with a single hickory lam that appeared to be parallel (no thickness taper).

Is he a member here?

[jhk1]

PM sent.