Recurve bow laminate help

Steve Rough

New member
Hey.
I'm wanting to build a one piece recurve bow.
I want to build it with different laminates of wood in a frame.
lve seen a style I like. It says to use strips of fibreglass laminate to strengthen it.
My problem is i cant find strips of fibreglass laminate in the uk.
Is there another method of making one. I still want to have the look of laminated wood.
Hope this makes sense. Ill try and upload a pic of one I like
 
D

Deleted member 7654

Guest
Pesronally I wouldn't touch f/glass with a bargepole, you'll need an epoxy glue, whereas with wood there are cheaper options like Resintite.
You can make a perfectly good bow with a variety of woods and say a Bamboo, Hickory or Ash backing (The belly wood is trickier).
There are various supplies of bow making materials and plenty of information out there.
Check out my blog (Bowyers Diary) over the last month where I made a bamboo backed Yew bow with some deflex reflex.
You can add curves to a simple self bow with dry heat (hot air gun) or steam.
A laminated bow can be pretty much made by numbers, the key thing is getting an even thickness taper, this is done with either patience, skill and hand tools or powertools by careful jigging up and running through bandsaw/planer/sander etc.
I qould suggest a WAQAP aproach...
Wrong as quick as possible! By getting stuck in quick you'll learn a lot of basics and get the mistakes out of the way, so that on your second attempt you will be more likely to produce the desired end result. Beginners typically aim for a 40 - 50# bow and end up with 20#
If you have the patience to trawl through my blog you will find tons of info.
A good 'standard' timber combination is hickory backed Lemonwood. As a general rule woods are better in tension than compression so it's easy to end up with the back overpowering the belly. A good suitable belly wood is the key, and keeping the backing fairly thin.
If you get the wrong woods you are doomed to failure, Say bamboo with an Ash belly would be a bad idea.
Del
 

Steve Rough

New member
Thanks for your help. I'll stay away from fibreglass then.
I have a length of ash so ill us that for the belly. How thick should the belly and back be?
What is resintite?
 
D

Deleted member 7654

Guest
Resintite is an adhesive, a very fine white powder you mix with water. It is the same sort of thing the Mosquito aircraft of WWII was glued together with.
Mr Google will find it for you...
How thick should the belly and back be? It depends on the style of bow, the types of wood and the required draw weight and length.
That's why I recommend having a quick go first.
One fact to remember is that stiffness of a bow limb is proportional to the cube of the thickness, thus small changes in thickness can make a big difference. The stiffness is proprtional to the width.
So twice as wide is twice as strong, but twice as thick is 2x2x2 that's times stronger.
I have some figures for self bows (Yew, Hazel and suchlike but no real data for backed or laminated bows.)
Go for a thin back lamination say 3-4mm maximum. The tillering of the bow is done by removing wood from the belly.
If you go for a modern shape (wide and relatively thin) there will be less strain on the wood than a longbow style.
Make the bow long, you can shorten it, it's very difficult to lengthen a bow if you start too short.
The belly can be two bits joined together with a slice, but it's best to have the back as a continuous strip if possible.
You can make a simple "pyramid" style bow with limbs of even thickness if it has plenty of width taper, say from 2" wide above the grip to about 1/4" at the tips (tips can be surprisingly thin as there is V little leverage at the tip).
Making 1/2 or 1/3 scale miniatures is a good way of experimenting and can produce surprisingly fast little bows. A miiature takes less wood and less work than a full sized bow.
Del
 
Top