Good Strong glue ?????

[Duke_Nukem]

Hi All,

im currently using Bison PU MAX to glue together 4 strips of laminates (20x40x100) of mahogany to form make a speargun...im not building a boat but since im gonna use wood and is gonna go in the water i though of asking here !!!!

I ve been told that the Bison i used is a fairly good product....however i heard about other products that Loctite has and after a wuick search i ended up that i could use the Hysol 2341 A+B two part glue and achieve good strength and resistace to sea water as this product is suitable for surf board laminates !!!!

Do any of you have any experience with this and what would you reccomend ???

Also can you please give me some information about SHEAR STRENGTH and PEEL STRENGTH of a glue...what do they mean by these terms ????


Thanks all in advance !!!

George

[Boatmik]

Howdy Duke,

Hi All,
Do any of you have any experience with this and what would you reccomend ???

The main thing is that water can't get into the wood. If you avoid that you can get away with timber with poor durability and glue of average durability.

The best way is to use epoxy to give the items a full three coats - see the section on precoating here
http://www.storerboatplans.com/Faq/faqindex.html

But rather than buying another glue - seeing it is not a whole boat that you have to protect - maybe you could just varnish it and see how it goes.

Also can you please give me some information about SHEAR STRENGTH and PEEL STRENGTH of a glue...what do they mean by these terms ????
Thanks all in advance !!!

George

If you use glue to laminate layers as you have, the glue is preventing the layers sliding across each other as you bend the laminate. That resistance is sheer strength.

Peel strength is (someone might have a better definition) but where the two surfaces are stronger that the glue that bonds them then it is the force required to tap a wedge into the join in the layers - grab both sides and start peeling the join open again. It is just about irrelevant for wood as the timber will be weaker than the glue and the geometry of the timber structure generally forces any crack of this type to follow the grain more than the glue join.

But is relevant for say plastics or metal gluing.

The main disadvantage of the PU glues for boatbuilding is that they require high clamping pressures and close fits. Not hard to acheive with your laminations but moving into more complex bevelled structures might require more labour and/or skill.

In those sorts of situations a gap filling glue like epoxy that doesn't require high clamping pressures may be easier for many.

Best wishes
Michael

[Duke_Nukem]

hi boatmik....

thanks for the reply....

im, trying to buy some west sytem stuff to experiment with..... and compare with bison pu max...then i ll take it from there judging on price, ease of use result etc !!!

Thanks.

George