I need a very strong wood glue for external structural project.
This is a number of vac-vac treated Glulam beans 270 x 90 and
tanalized 150 x 150 posts.
This will be made up of a number of posts joined with gallows
brackets
to beams.

The posts will have a 90 x 270 notch cut in the top so Glulam is
resting for it's full thickness and depth - for some reason I can't
think of name for the joint ..


This and the 45 degree struts that form the gallows brackets are
trough bolted with 10mm thick steel Y plates ... on both sides -
holds
everything square.
simple sketch on: (45 deg struts left out for clarity)
http://tinyurl.com/574dhz

I thought it worth putting a good glue on the Glulam to post joint,
and the 45 strut faces.

Had thought about inserting dowels or biscuits - but been dissuaded.

Needs to be weatherproof glue, with moderate gap filling
capabilities,
no requirement for quick setting or initial grab .. quick googling
around has told me that Phenol Formaldehyde, Urea Formaldehyde or
resicornal glues would be best ...

And it seems a polyurethane glue is unsuitable ?

On previous jobs over the years I used Cascamite ... but guess better
glues must now exist.

Welcome advice .. and some 'trade names' of what glue to look for.

"Osprey" wrote in message
...
Needs to be weatherproof glue, with moderate gap filling
capabilities,
no requirement for quick setting or initial grab .. quick googling
around has told me that Phenol Formaldehyde, Urea Formaldehyde or
resicornal glues would be best ...

And it seems a polyurethane glue is unsuitable ?

On previous jobs over the years I used Cascamite ... but guess better
glues must now exist.

Welcome advice .. and some 'trade names' of what glue to look for.



Polyurethane can be strong and can fill gaps but does neither very well at
the same time. I'd look for an epoxy or WeldWood.

Osprey wrote:

The posts will have a 90 x 270 notch cut in the top so Glulam is
resting for it's full thickness and depth - for some reason I can't
think of name for the joint ..

From the picture it's sort of a modified half-lap joint, where only one
member is actually cut.

I thought it worth putting a good glue on the Glulam to post joint,
and the 45 strut faces.

If you glue the whole notch, any rigid glue will likely crack fairly
soon due to cross-grain movement. If you're going to glue it, I'd
suggest only gluing a few inches of the post above the notch.

Given the steel plates, I'd say glue is unnecessary.

Chris

"Osprey" wrote:


I need a very strong wood glue for external structural project.

Laminating epoxy with a slow hardener and thickened with
micro-balloons.

Anything else is down hill from there.

Check out Gougeon Bros for details.

Lew