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Main Boards => The Bowyer's Bench => Topic started by: tooch on June 02, 2017, 12:25:00 AM

Title: what wood to accompany bamboo and osage?
Post by: tooch on June 02, 2017, 12:25:00 AM
Hi all!  Building my first longbow.  Wood laminated with slight d/r aiming for the mid thirties pound draw range and maybe 60-62" nock to nock.

So far I have bamboo backing from echo archery that is about 1/8"

Handle will be osage as well.

I have a very thin piece of osage, I was hoping to go just BBO, but will have to add something else I think and figure why not something besides Osage.

Basically I am looking for a recommendation on a piece of lumber that would go well with these two that is about 1/2" x 1.5" x 70" or so.

What about Ipe? and where to find it.  Any cheap options out there?

I believe I will be using Unibond 800 for the glue up.

Thanks
Title: Re: what wood to accompany bamboo and osage?
Post by: mikkekeswick on June 02, 2017, 02:40:00 AM
It is best to pick a lower density wood for the core. Corers are really only spacers between the back and belly surfaces that are doing the work.
Maple, b.walnut,sycamore or a similar mid density wood woulkd be my choice. B.walnut looks well against osage.
I would put about an 0.002 taper on it. Or if going full pyramid with the limb profile 0.001.
Title: Re: what wood to accompany bamboo and osage?
Post by: Roy from Pa on June 02, 2017, 06:17:00 AM
How thick is the piece of Osage you have?
Title: Re: what wood to accompany bamboo and osage?
Post by: Bowjunkie on June 02, 2017, 08:27:00 AM
That's what I was wondering, how thick is the osage, and is it already brought to accurate dimensions throughout? Is it parallel or tapered? Is it a GOOD piece, with no knots or severe ring runout?
Title: Re: what wood to accompany bamboo and osage?
Post by: Pat B on June 02, 2017, 09:25:00 AM
You might already have what you need for a 30# bow just with the boo and thin osage belly.
Title: Re: what wood to accompany bamboo and osage?
Post by: tooch on June 02, 2017, 09:59:00 AM
The osage I have is coming from OMC bowyer supply.

1.5" wide
.050 thick (inches??)
.002 taper

its 2 36" pieces.  What exactly does .05 thick mean?

I ordered rather impulsively.   :D
Title: Re: what wood to accompany bamboo and osage?
Post by: tooch on June 02, 2017, 10:00:00 AM
I guess I was hoping for a piece about 3/8" to 1/2" thick to start from.
Title: Re: what wood to accompany bamboo and osage?
Post by: Pat B on June 02, 2017, 11:25:00 AM
You could probably build a 60# bow with the 1/2" osage and boo backing.
Title: Re: what wood to accompany bamboo and osage?
Post by: tooch on June 02, 2017, 11:35:00 AM
Well I currently shoot a 40# @26 and I'm very inconsistent when it comes to a 30-60 arrow 3D shoots so I want something lighter to work on my form.  

Trying to figure out what .050 thick means.  I'd understand if it said 0.05"
Title: Re: what wood to accompany bamboo and osage?
Post by: Bvas on June 02, 2017, 11:41:00 AM
0.050" is a thin lamination.
It is 5/100 of an inch thick, or less than 1/16" thick.
Title: Re: what wood to accompany bamboo and osage?
Post by: kennym on June 02, 2017, 11:55:00 AM
I always use all 3 numbers like .050, because I deal in thousandths of an inch to keep it simple.

So fifty thousandths is same as five hundredths.

Right Roy?  :D
Title: Re: what wood to accompany bamboo and osage?
Post by: Bvas on June 02, 2017, 01:11:00 PM
That's why I added the 1/16".......so Roy could follow along.   :biglaugh:
Title: Re: what wood to accompany bamboo and osage?
Post by: BMorv on June 02, 2017, 02:49:00 PM
I am a little confused by the numbers you show.  A tapered lam usually is represented by the thick end thickness, so in your case 0.050".  Then it tapers out at a certain taper rate, in your case 0.002" per inch of length.  On a 36" lam with 0.002" taper, it will be 0.072" thinner on the thin side than the thick side.  That's not possible if it only started at 0.050".  
Or am I missing something?
It would clear things up if you could measure both the thick end and the thin end of one of your lams.
Title: Re: what wood to accompany bamboo and osage?
Post by: tooch on June 02, 2017, 03:01:00 PM
I am also confused by the numbers!

Just got off the phone with OMC bowyer supply and he set me up with a more proper thickness and taper to back with bamboo.   Should have it sometime next week.

I think I will use a hacksaw blade to gently score the wood before glueing up to the bamboo with Unibond 800, unless y'all suggest something else
Title: Re: what wood to accompany bamboo and osage?
Post by: Bowjunkie on June 02, 2017, 03:58:00 PM
Hacksaw blade scoring and Unibond should work.

Your bamboo should be tapered also. 1/8" thick at the handle and 1/16" at the tips.

What are the dimensions of the osage now going to be?
Title: Re: what wood to accompany bamboo and osage?
Post by: Roy from Pa on June 02, 2017, 04:02:00 PM
A 3/8th or .375 thick Osage belly lam will get you into the mid 30#'s with no problem at 60-62" nock to nock. Might even come out more on the 40# + side. But it's always nice to have a little extra wood.

Watch your mouth Kenny.. LOL
Title: Re: what wood to accompany bamboo and osage?
Post by: Mad Max on June 02, 2017, 05:40:00 PM
When you get to low poundage bows you can't always
use 3 or 4 pieces in a stack.
I have made some with 2 fiberglass and 1 taper lam.
Listen to Roy on a BBO  

Dial Calipers
1 revolution = 1/10 of a inch or.100
  https://www.google.com/search?q=Dial+calipers&source=lnms&tbm=isch&sa=X&ved=0ahUKEwiSuoS9j6DUAhWDDiwKHTLZBFEQ_AUICygC&biw=1093&bih=510
Title: Re: what wood to accompany bamboo and osage?
Post by: Bowjunkie on June 02, 2017, 06:40:00 PM
Yep, listen to Roy.   :notworthy:
Title: Re: what wood to accompany bamboo and osage?
Post by: Mad Max on June 02, 2017, 08:46:00 PM
LOL
Title: Re: what wood to accompany bamboo and osage?
Post by: tooch on June 12, 2017, 08:15:00 PM
Osage is here

Both pieces just over a 1/4" tapering to 1/4"

36" Long


I also got a nice riser block, and am thinking about cutting a power lam from it to go between the bamboo and the 1/4" osage in order to take stress off my handle.
Title: Re: what wood to accompany bamboo and osage?
Post by: Pat B on June 13, 2017, 08:49:00 AM
Not much of a taper there, tooch.    :knothead:  
I assume you mean taper from 1/2" to 1/4"
Title: Re: what wood to accompany bamboo and osage?
Post by: tooch on June 13, 2017, 10:45:00 AM
No i meant what I typed.  Not much of a taper at all indeed.  On both there is one side just over 1/4" and the other side is right at 1/4"
Title: Re: what wood to accompany bamboo and osage?
Post by: Roy from Pa on June 13, 2017, 12:45:00 PM
1/4" thick Osage will be fine for the belly lam. But for a bow in the mid 30 pound range, you want to add a core lam of about 1/16th" to 1/8" thick.