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Main Boards => The Bowyer's Bench => Topic started by: bigcountry on March 17, 2009, 10:40:00 AM

Title: IPE Bamboo, TBIII or epoxy
Post by: bigcountry on March 17, 2009, 10:40:00 AM
Well, almost got all my pieces together ready for glue up.  I still have to make a power lam, and tweak my bamboo some.  

So, I was planning on glue with titebond III.  I talked with a few bowyers who say they do it, but everything better be smooth and flat as possible. Anyone have a failure with boo glueup with TB III?

But since this is my first glue up, it sounds like smooth on would be safer.  But I really don't want to go thru the process of heat box and lightbulbs, etc.

Any problems with TBIII?
Title: Re: IPE Bamboo, TBIII or epoxy
Post by: Pat B on March 17, 2009, 11:15:00 AM
I've used TBIII with boo/ipe bows and none have come apart. Your ipe will already be relatively flat and the boo will be when you have it ready to go.
  Another option that I have had luck with it Urac. You will need at least 70deg(F) for it to cure. If you use Urac or epoxy, you will need to groove(with toothing plane or hacksaw blade) or rough up both gluing surfaces.
Title: Re: IPE Bamboo, TBIII or epoxy
Post by: bigcountry on March 17, 2009, 04:08:00 PM
Pat, another guy suggested a "power Lam". Basically a (11" piece 1/8" thick tapered down to razor thin) between the boo and IPE at the handle.  This is to ensure that I have no flex to pop off my handle.

This is the only area I figured I would have to worry so much.  Also I am going to reflex the tips about 2.5".

My IPE is 5/8" thick at the handle.  He said I shouldn't have any issues with 3/4" at the handle but would power lam a 5/8" piece.
Title: Re: IPE Bamboo, TBIII or epoxy
Post by: Pat B on March 17, 2009, 04:25:00 PM
I have not done a power lam before but a 1/4" thick piece should be enough.Just the extra glue line should add some strength.  If your belly is below the plain of the handle you shouldn't need a power lam anyway.
  Also you can make your handle riser out or 2 or 3 thin lams of graduated lengths instead of one thick one and even if your handle area does flex a bit the handle should flex with it.
Are you going to glue up your bow with Perry Reflex or are you going to recurve the tips?
Title: Re: IPE Bamboo, TBIII or epoxy
Post by: bigcountry on March 17, 2009, 04:38:00 PM
This first one, I will just reflex the tips.  I want to try a trilam one day with a perry reflex.
Title: Re: IPE Bamboo, TBIII or epoxy
Post by: bigcountry on March 17, 2009, 11:27:00 PM
Guys, is TBIII that strong?  Has anyone had any "backing" failures with it?
Title: Re: IPE Bamboo, TBIII or epoxy
Post by: Pat B on March 18, 2009, 08:40:00 AM
TBIII, when cured and if both surfaces are clean and properly mated, is stronger than the wood you glued.
Title: Re: IPE Bamboo, TBIII or epoxy
Post by: bigcountry on March 18, 2009, 09:20:00 AM
Quote
Originally posted by Pat B:
TBIII, when cured and if both surfaces are clean and properly mated, is stronger than the wood you glued.
Good deal.  I will post my results.  :)
Title: Re: IPE Bamboo, TBIII or epoxy
Post by: Pat B on March 18, 2009, 09:24:00 AM
Be sure to degrease the ipe well. It is a very oily wood.
Title: Re: IPE Bamboo, TBIII or epoxy
Post by: ChristopherO on March 18, 2009, 11:32:00 AM
TTB111 has worked well for me, too.  Just don't starve the glue joint with too tight of clamps.  It helps if you keep the boo nodes away from any tapered areas as they tend to be stiff and then it is tempting to over clamp that area to keep it down.
Title: Re: IPE Bamboo, TBIII or epoxy
Post by: bmgarto on March 19, 2009, 12:09:00 PM
I have had it fail twice. I think IPE is too oily. I would get URAC 185 to be safe.
Title: Re: IPE Bamboo, TBIII or epoxy
Post by: soopernate on March 19, 2009, 12:17:00 PM
I have never had a TB3 failure on ipe boo combinations.  The only people I know who have had failures used a toothing plane to cut grooves...THE DIRECTIONS on the bottle specify close fitting smooth joints for best results.  IT is not a gap filling epoxy at all and should not bet treated as such
Title: Re: IPE Bamboo, TBIII or epoxy
Post by: bmgarto on March 20, 2009, 03:43:00 PM
Mine failed with two smooth surfaces per the directions. Just my experience.
Title: Re: IPE Bamboo, TBIII or epoxy
Post by: Apex Predator on March 20, 2009, 04:05:00 PM
I've never had a glue joint failure with TBIII.  I've used in on 10-12 boo backed bows.
Title: Re: IPE Bamboo, TBIII or epoxy
Post by: chrisg on March 21, 2009, 03:23:00 PM
Ipe boo bows need to have clean and degreased joints. How you do this is the trick, I use acetone and score the surfaces very lightly using a blunt hacksaw blade, more like little riffles than deep scoring. I use smooth on and leave the
surfaces to air for  an hour or two before gluing, if you leave them in a hot box for a couple of hours and then degrease them so much the better. After degrease leave them in the sun or air for a few minutes for volatile oils to evaporate. Don't over tighten clamps.
chrisg