Why 1st paint coat takes longer to dry?
- Thread starter Howie
- Start date
Dave Wermuth
Who hid my paddle?
I've not experienced those events. My first coat of filler feels like sand paper as i no longer burn the canvas fuzz off. My first coat of paint is over primer.
OP
OP
Howie
Wooden Canoe Maniac
Yeah, I should have added that I don't prime - the 1st coat goes right on the filled canvas. And that I sand the filled canvas before I paint. Although sanded canvas surface feels extremely smooth maybe I'm raising or exposing canvas fibers? - although I never sand far enough to see the canvas.
Todd Bradshaw
Sailmaker
Since filler often takes quite a while to dry there could be something still working out of it that reacts with the paint and slows its drying time. If you are sanding right before painting, there is an even better chance of exposing something that hasn't had time to totally air-cure and could still have a higher than ideal solvent content for overcoating. Filler also has a pretty high mineral content, and just like the marine barrier coatings, moisture (or anything else, like solvents) literally has to zig-zag around the particles to get through it (or out of it). You could certainly get to a situation where the filler has hardened, but is still slowly trickling out a little bit of evaporating solvents for quite some time. As long as the paint will eventually dry and is well attached to the surface, I'd just plan on the first coats usually taking longer to dry and live with it. After that first coat dries, the second will likely dry faster because the first one has sealed the surface.
OP
OP
Howie
Wooden Canoe Maniac
Yup, that's what I've been thinking. I wait from 6 to 8 weeks for the canvas to dry (8 weeks for this latest canoe), and I give it a light sanding within the 1st week, so I think it's as dry as it's likely to get. And as you say, subsequent coats are dry in 24 hours and are relatively smooth.
