Cold weather wood finishing tips?

[ChristyM]

I know next to nothing about finishing wood. I mean, I’ve done it, but mostly I just Googled and winged it. My SIL has asked me to make a sign for their VT ski condo that will hang outside. She’s opted for cut out letters on a background as opposed to etching or painting them on a board. I obviously would like it to hold together over time.

I’m thinking of trying to nab some pallet wood for the background and then just use baltic birch for the letters. I’m going to paint the letters and then glue them on the backing. My questions:

1. Should I finish the letters front and back before attaching? Or glue on first and then finish the whole thing together?
2. Any tips on a good glue for holding up in cold weather? Is glue a bad choice entirely?
3. I was thinking of using some sort of spar varnish or poly so it holds up in the extreme weather changes. Thoughts?
4. Any other tips for making sure this holds up?

Thanks!

[jfruhling]

I would obviously utilize an exterior grade paint/stain/weatherproofing etc - personally if it were me id coat the entire piece front back sides etc then attach
titebond is a favorite amongst the woodwork community they make an exterior use and
it is incredible

[evansd2]

Titebond III is waterproof. Not sure about a specific exterior use formula but it wouldn’t surprise me. They have lots of different formulae.

[julybighouse]

One thing to consider, even exterior paint degrades over time. 3 coats of Polyurethane act like encasing the entire thing in clear plastic. Pretty much the only thing that would happen to the sign underneath it is discoloration from UV.

[rmarvell]

Hi try to use solid wood, avoid mdf or ply the edges will not handle the elements unless well protected.

If it’s exposed to the elements directly the finish needs to be strong so marine varnish or sorts.
If it’s just outside but protected,
a good varnish like general finishes will be fine.

Alternatively you can be open and say the elements will not treat this well - so build a frame type design where you can pop out the sign every 2/3 years and replace it as it ages.

[ChristyM]

Thanks, all. It’s going outside a ski condo. It will have plenty of exposure! I don’t need it to last an eternity, but would prefer to not have letters falling off.

I checked the Titebond site and it looks like their high-end glue is a good bet.

[mrinken]

So in my experience (which isn’t extensive with outdoor in my 25+ year WWing history), always glue wood to wood unfinished and yes, Titebond 2 or 3 should be fine, although recently Ive been building a Teardrop Trailer and it’s been outside for about 4 months now and some of the finish pieces are pulling up - I used Titebond 2 to hold those down, so something different that’s listed as outdoor waterproof might be better. I dunno. Most everything I’ve ever done for an outside project has always had fasteners of some kind - pin nails, screws, etc. If it’s just a 1/8 inch to 1/4 inch thick letter, that would be overkill. Glue should work.

As far as finish is concerned, if you’re sticking with a natural look - Spar Urethane is what you want. Polyurethane can work, but it’s not meant to take the UV. Spar is specific to outdoor / marine environments. Keep in mind you’ll need about 6-8 coats to really make it effective. I have 4 on my tear drop trailer and it’s not enough. You also might want to run a very very thin bead of silicone around the letters after you are finished with your last coat. Water will pool / get into any microscopic crack in anything, so having a good outdoor silicone will help quite a bit. It’ll take a while and you want a really really small bead so it’s not noticeable, but it’ll be worth it.

[ChristyM]

Very helpful. Thank you! I did notice that Titebond 2 is water resistant, while TB3 is waterproof.

[mrinken]

So I remember reading an article in Wood magazine a few years ago testing TB2 and TB3 - I don’t remember the results but I remember one of the critical feedback items was TB2 was far superior for some reason. I’ll have to dig through my collection and see if I can find that. I know it’s why I continued to use TB2 over TB3 in just about everything. But yes, use TB3 for this application. Also - make sure you have coverage on the whole surface, don’t just put a bead on the wood. Put a good bead on there, then use a paint stirrer or better yet a foam roller to ensure full surface coverage. And then put a ton of weight on it as it dries. Bricks, paint cans, whatever you have that’s heavy.

For surface gluing like that, I usually cover it with wax paper after gluing, put another board the same size on top then weight the crap out of it. Wait overnight then remove. You just want to ensure it’s 100% dry.

[ChristyM]

Excellent tips. Thank you!