Exterior adhesive

[stuckinthemud]

I am renovating some very old wooden folding garage doors. They are faced with tongue and groove boards that look a lot like old floor boards except they have simple mouldings run along the t&g. They need filling in places and some splines letting in. Any recommendations for an exterior glue? Was thinking of yellow glue or an expanding pu type adhesive. Thoughts?

 

[Ollie78]

Expanding pu is great but it can go everywhere. I would suggest an epoxy like timbabuild or similar but you need the double gun and it is expensive, great stuff though.

This is a little bit left field but Stixall or other hybrid polymers might be an idea.
I discovered how good they are when I used some to "temporarily" attach a fixed casement in place while I re-made it (there were measurement issues !!) when I came back a few weeks later it was incredibly hard to remove, so much so I had to cut it out with a Fein saw. Since then I have used it for several glueing jobs to great effect. Also its paintable, will fill gaps and is not silly money.

Ollie

 

[ChaiLatte]

The two glues mentioned by the OP have one main difference: their gap-filling ability.

If the joints to be made are wood-to-wood (no gaps), any external wood adhesive (blue EvoStik or Everbuild D4) will do well.

If there are gaps to fill, the PU or hybrid polymer would work well. Take good note of the 'expanding' in the PU glue. Unless you clamp the pieces very well, the expansion can displace the pieces being glued. Polymer adhesives do not expand so can be more sparingly clamped. Removing excess PU is messy when it is wet but easy when it is cured; trimming excess cured polymer is difficult (so is best done before it sets, but can be messy).

Hence you might need two glues and considered application of each.

 

[stuckinthemud]

There will be an element of gap-filling, and even just filling of splits, dents old nail-holes, joints and so-on. Also, some joints are ok and just need a dap of glue.

 

[ChaiLatte]

...filling of splits, dents old nail-holes, joints and so-on.

Conventionally, we would use someting called a 'filler' for that purpose. You can buy exterior-rated decorator's caulk, which has the benefit of flexibility to it.

Have you been eating too much CT1? Even as far back as the 'Wash and Go' era, there seems to be an increasing trend towards a 'one product for everything' idea.

 

[stuckinthemud]

It’s about waste/cost/storage- some glues can be thickened into fillers, most fillers have limited shelf life once open. Three products cost three times as much…. I only have this job requiring exterior products and very rarely use even glues in the normal course of things, so, what isn’t used will get thrown out. Also, the doors are West facing, although sheltered by a high wall, and deal with a lot of rain. My first thought was a yellow PVA thickened with saw dust but not sure how weatherproof that is