Primitive Archer

Main Discussion Area => Bows => Topic started by: Mad Max on October 11, 2013, 08:47:10 pm

Title: bamboo
Post by: Mad Max on October 11, 2013, 08:47:10 pm
can you heat or steam bend bamboo core laminations
Title: Re: bamboo
Post by: NeolithicMan on October 11, 2013, 09:12:11 pm
yes, i saw a special on korean bow making and the master bowyer used a pot full of coals with a screen cover and bent the boo in a special jig. i use steam for all my wood bending so far, feels a little safer. maybe there was steam being used in the before mentioned special, i just didnt not see any when i was watching.
Title: Re: bamboo
Post by: huisme on October 11, 2013, 09:22:22 pm
Yep, quite safely in fact.
Title: Re: bamboo
Post by: Mad Max on October 11, 2013, 09:23:41 pm
bamboo lams are glued / epoxyed or something
I am worried they will come apart
I have a 6" radius on my recurves form and my bamboos are .110 thick
do they need to be heat bent       or just glue them up
Title: Re: bamboo
Post by: BowEd on October 11, 2013, 10:08:55 pm
That's less than an 1/8"thick,but that's a tight radius to conform to.You might need to thin that some yet.I'm not totally into laminated bows but have done 8 or 10 bamboo backed bows and I think you should be able to get that to bond if wrapped really tight with innertube.
Title: Re: bamboo
Post by: echatham on October 11, 2013, 10:58:59 pm
just a data point for you,  the other day a friend of mine boiled a piece of bamboo and osage clamped together for about 15 minutes, then bent 60 degree recurves  in them together.  the osage held virtually all of the 60 degrees, and the bamboo held about40 degrees or so.   i imagine at glue up, the bamboo will conform to the osage.
Title: Re: bamboo
Post by: Mad Max on October 13, 2013, 12:37:32 am
POOR FOLK BOWS has a build along where he has .140 tappered and .102  paralell lams (bamboo)
he heat bends the bamboo backing (with nodes) but not the lams and bends and glues to a 6 1/2" radius (for the tips)
Title: Re: bamboo
Post by: crooketarrow on October 13, 2013, 10:26:37 am
  You can't beed the boo after it's been glued up.
  The heat will make it come apart.
Title: Re: bamboo
Post by: bushboy on October 13, 2013, 11:18:25 am
If you clamp the boo to the recurve and mildly dry heat,it makes for a better fit.try to keep the nodes away from the apex of the bend.
Title: Re: bamboo
Post by: dragonman on October 13, 2013, 04:57:47 pm
if you can squash the bamboo into the form by hand without straining, then the epoxy will hold it...  no problem, if you glue and clamp it properly
Title: Re: bamboo
Post by: Mad Max on October 13, 2013, 08:43:19 pm
  You can't beed the boo after it's been glued up.
  The heat will make it come apart.
I was wanting to pre bend (heat) befor glue up

If you clamp the boo to the recurve and mildly dry heat,it makes for a better fit.try to keep the nodes away from the apex of the bend.
   Bamboo laminations (no nodes)

if you can squash the bamboo into the form by hand without straining, then the epoxy will hold it...  no problem, if you glue and clamp it properly
  i'am scared they will break if i squash them into the form :-\ :(
Title: Re: bamboo
Post by: Mad Max on October 20, 2013, 01:02:52 pm
That's less than an 1/8"thick,but that's a tight radius to conform to.You might need to thin that some yet.I'm not totally into laminated bows but have done 8 or 10 bamboo backed bows and I think you should be able to get that to bond if wrapped really tight with innertube.
I reduced my lam to .070 and added one more,   the glue up went fine
I am going to take it out of the form monday. :) 8)