Thinking about a TRI-LAM recipe...

[EASTERNARCHER]

Anybody got comments or advise about the following recipe"

1/8" hickory backing
jatoba, ash, or maple core
maple belly.

thinking of something like 64-66" ntn
50 - 55lbs @ 28".

Anybody got some suggestions for tri-lan recipes?

After I finish my Dryad blank of course.

[BamBooBender]

What you suggested sounds pretty good. You might want something denser for the belly though like osage, ipe, bullet wood, etc..

I think the basic idea is; wood that is strong in tension for the back, middle lam should be something light weight, and the belly should be really dense.

[BamBooBender]

On second thought maybe you should pm Javaman. If I remember rightly he used to make some downright beautiful tri-lam elb's.

[KrEn]

-hickory back
-maple core
-jatoba belly

Will make a fine bow

Make the maple/core max. 3-4mm thick and consider tapering it

You dont need heavy wood in the core
Avoid ash as belly behind hickory, unless very thin hickory
Always use the heaviest wood as belly, unless it is just an accent stripe

K

[EASTERNARCHER]

Originally posted by KrEn:
[QB] -hickory back
-maple core
-jatoba belly

Yeah, after thinking on it, I thought jatoba should go as the belly.
Maple or boo flooring for mid-lam then?
How thick should the lams be? other than the hickory, which is already milled to 1/8".

Can the belly lam lap out over the riser fades or glue up riser over all belly lam.

[Buemaker]

In his book; The Heritage of The Longbow Pip Bickerstaffe mention many wood species that are suitable in a tri lam ELB.
 Bue--.

[Bob Barnes]

Bue...I'd like to read that.  Today I did a glue-up with hickory backing, 1/8" yew core and an osage belly...I wanted to try something besides bamboo on osage.
Bob

[BamBooBender]

That sounds like a good recipe Bob.

[EASTERNARCHER]

Hey Bob, let me know how that works for ya...
how thick is the belly wood and hickory back?

[EASTERNARCHER]

VERTICAL GRAIN OR FLAT GRAIN HICKORY BACKING?

[Pat B]

On a hickory backed bow you can always reduce the hickory after the bow is glued up.  This will help if the weight needs reducing or the tiller needs adjustment.
  A few years ago I made a boo backed yew bow. It fretted badly just below the handle so I stuck it in the corner. Earlier this year I took it out, ground the yew until the fret was gone(to about 1/8") and added osage slats to the belly and retillered. This bow came out great. It is a hard hitting bow that is very light in the hand. I would use the same combo with hickory backing without hesitation.   Pat

[Bob Barnes]

I used 3/16" quarter sawn hickory, 1/8" yew core, and the osage is about 1/2" thick.  I glued in 2" of deflex and 3" of reflex...it came off the form with the limbs only sitting  about 1/8" above the center supports.  I glued a 14" piece of walnut on yesterday for the grip.  I'll know more today when I pull the clamps and reduce the width from the 1 3/4" current size.  I'm thinking about 1 1/8 to 1 1/4" wide tapering to 1/2" or less at the tips and probably 64" long n-t-n...???  probably 55#@27"...
How will hickory backing compare to bamboo for strength and such?

[Bob at Work]

The glue up looks great ... it may take set or break but I like it so far.  Since you asked about different combinations and since I always wanted to try it...I just glued another one up with hickory backing, a 1/4" thick by 16" double tapered riser lam (acts as a stiffener between the backing and belly wood) and a beautiful walnut belly with near perfect grain from end to end...the walnut was bought in 1983 from a cabinet shop and I've been saving it ever since...  
Bob

[EASTERNARCHER]

COOL...CAN'T WAIT TO SEE PICS!!!

[tree dancer]

Bob  Can we get a picture? I would like to know more about that riser lam.

[EASTERNARCHER]

Oh Bob...can we see some pics of your tri-lam you talked about before Christmas???Would love to see how it turned out.

[Ol Man]

Got me a concoction that I am going to start - Bamboo backed (with nodes) Fastflex (Bamboo-lam), Walnut then Bamboo belly (with nodes)  It will be a 4" reflex - Perry Style stave.  With Bacote Riser!

[Bob Barnes]

I took a few pics of the glue ups but got myself a mega dose of carbon monoxide too...man, what a headache !  I don't know how to post pics but I can send a couple if someone wants.
I like the hickory/yew/osage best so far.  The glue ups with bulletwood seem very very heavy (mass)  compared to the others.  I'm thinking it will not take much of it  to make a heavy draw weight bow.
Bob