Which Wood Glue

[Rick Hughes]

Been advised that on a structural external timber project, that Polyurethane glue is not that good a choice.

I have used Cascamite in the past, is there anything better ?

Will be gluing 150 x 150 posts to 150 x 150 gallows brackets, and to Glulam beams .... and such like. Material is pressure treated softwood.

Glue will not be main strength ... thru bolted steel plates will do that, so glue is secondary fix, require a moderate amount of gap filling ability, and not prone to UV degradation - and of course must be waterproof.

[The Natural Philosopher]

The troubgle is with non gapfilling and non flexible glues outside, is that humidity changes cause cracking and splitting of the glue joint. Frankly I think that anything BUT polyurethane is a waste of time.

And even that is not a lot of cop either.

Oustide? Use ruddy great galvanized bolts, screws or nails and leave it at that, or go trad and make mortice and tenon and use pegs.

[Pete C]

Were you advised there are very different types of polyurethane glues?

I'd have a look at these:

3M 5200 is another one.

Wickes do something along this line but no idea how good it is and maybe not much cheaper than the others.

cheers, Pete

[robgraham]

As shown by Fred Dibner on the box this evening !!

Rob

[Andy]

What's wrong with exterior PVA? I used it to laminate an arch together and it's gone thee years open to the elements with no problems.

Andy.