Grit in paint

[Greenthumbed]

Hi all,
I am nearing the completion of a restoration of a ‘72 Chestnut Prospector. I just applied the third coat of paint yesterday evening. On all three coats I have had grit in the finish. I can’t figure out what is causing it.
The paint I am using is:
Home hardware brand Rustoleum.
I am applying it with a foam roller and tipping with foam brush. I changed rollers, brush and paint tray for brand new stuff for this last coat.
After sanding I vacuum the hull and wipe down with a tack cloth.
Now my shop is dusty for sure so on this last coat I painted outside. Same result.
The grit is not everywhere, but is heavy in places.
I am planning on a forth this weekend and would like this problem solved before then.
Has anyone had issues like this and found a solution?
Thanks,
Chad

 

[Andre Cloutier]

after sanding i wipe with thinner and a rag before tacking, for what its worth. Might be bad rollers or bad paint, use process of elimination. cheap brushes always need washing and spinning after manufacture. foam should be clean but if the foam rollers are coming apart thats likely it.

 

[David Satter]

Yes, Use a paint strainer and a good brush. Clean that brush well, Rince and spin a couple of times. Sometimes I even vacuum the brush. If you're using a foam brush use a good one. Knock down all that grit with 220 before your next coat.

 

[Greenthumbed]

Thanks fellas
I’ll try it again with strained paint, better tools and crossed fingers!

 

[Michael Grace]

Paint straining is an excellent practice, and you should do it. However, given that you're having these "grit" inclusions in certain regions of the canoe and not others, you might simply need to clean the canoe better before painting. It is easy to miss spots with the vacuum and tack cloth. You might even be missing spots where the outwales or keel (if it has one) meet the canvas, and dragging dust-contaminated paint out from there. A very low-angle light is your friend - it will allow you to see patches of dusty might miss otherwise.