Primitive Archer

Main Discussion Area => Bows => Topic started by: Hickoryswitch on May 03, 2008, 12:57:30 am

Title: Bamboo bending
Post by: Hickoryswitch on May 03, 2008, 12:57:30 am

Can bamboo be bent into a recurve shape with heat.  What i'm wantin to do is build a bamboo backe recurve. If anyone could help me I would really appreciate it.  Maybe you could tell me if my idea will even work. I have joined two billets which i sawed to 13/8'' wide and 5/16 thick 64'' long. I'm wanting to put about 2'' of deflex and recurve the tips bout 5.  If this won't work someone please tell me now. I hate it when these things blow up it hurts. ;D

Title: Re: Bamboo bending
Post by: sailordad on May 03, 2008, 01:13:23 am

not sure about a recurve,but have seen many boo/ hickory and boo/ipe and boo/blackwalnut reflex deflex style bows.so it can be bent backwards,how far one could go safely,hmmm not real sure.that would be a cool bow though 8).
i hope someone with more knowledge chimes up for ya. this could be very interesting to see a completed boo recurve. good luck.




oh ya,got the pm,appreciate it man.
i'll keep you updated.

                                                                         tim

Title: Re: Bamboo bending
Post by: PatM on May 03, 2008, 11:07:43 am

I'm pretty sure you could heat the strips where you are going to recurve them with direct heat and pre-shape them rather than just bending them with clamps.
 Bamboo gets very plastic with heat. They sell bamboo arches for gardening that are heated and bent almost in a circle without cracking.
 For a larger curve it can just be clamped and glued.

Title: Re: Bamboo bending
Post by: Hickoryswitch on May 03, 2008, 03:11:02 pm

Thanks I just may be able to make this one work then. I thought it would be an interesting bow and should be fast. At least i hope. ;D

Thanks,
Wayne

Title: Re: Bamboo bending
Post by: markinengland on May 03, 2008, 06:35:06 pm

I have a little unfinished bamboo selfbow. I heat treated some recurve into it and it stayed recurved if somewhat unstable. Heat treating increased the strength of the bow as well as the shape.
Heat treating allows the bamboo to be bent but alters the properties. I have heard that the heat treating increases the compression strength fine for a bow belly but I am not sure what effect it has on the tension strength when used on a backing.
Bamboo cn be thinned to the point where it would follow any normal recurve without real problems.
Mark in England

Title: Re: Bamboo bending
Post by: Hickoryswitch on May 04, 2008, 09:25:12 am

Thanks Mark in England. I was kinda wondering if it would temper the bamboo and possibly cause a problem. Three rivers sells a backing strip that is tempered. Does it make boo weaker in tension than raw?