Shop doors: What glue?

[Warren Clemans]

I'm finally almost ready to glue up my shop doors. Each door is 3' x 7'6", 2" thick doug fir, with mortise and tennon joinery. They will be finished with spar varnish. My adhesive choices are narrowed down to:

-marine epoxy
-polyurethane
-Titebond III

I've been leaning toward the Titebond III. Pros and cons of each, as I understand them:

Epoxy. Pros: strong, waterproof. Cons: I've read that UV exposure is an issue for epoxy, but I'm not sure whether that is a problem for joinery, or just for applications where the epoxy is used as a coating. I need to glue up the door panels (this weekend's project), so at least that glue line will be exposed to sunlight. I've read old threads where people say they use epoxy for exterior doors, but they may be painting them.

Polyurethane. Pros: Water resistance. Cons: Strength. I'm concerned about polyurethane's poor showing in recent magazine tests.

Titebond. Pros: Easy to use, strong, water resistant. Cons: I've re-read the thread that Bob Smalser started that points out that Titebond is not very reparable, but I can't decide whether that's an issue for exterior doors. I'm planning on supporting them on an overhead track, so sagging shouldn't be an issue. I'm not saying they'll never need to be repaired, but I hope they'll last a good long while without needing it. Maybe by then we'll have an adhesive that sticks to Titebond.

What would you use?

Thanks for any advice.

Warren

[Ed Peters]

is more than adequate for your purposes unless these doors are to be mounted on a submarine. As to epoxies, they are unaffected by UV exposure when they are contained in the joinery. As a top coat, they really suck.

Ed

[Jamie Buxton]

That sounds like a big glue-up. Another advantage of epoxy is that it can have a longer working time than Titebond.