Prepping plywood for paint

[Lex Boegen]

I use dewaxed shellac. It's frequently sold as "sanding sealer". Any type of film finish can be applied over it (paint, varnish, etc.).

[Alex Borshov]

I ended up getting Zinsser Sealcoat and the cheapie spray gun from Harbor Freight. Both are working great so far. I need to work on the ventilation in my garage, though. I got the heater cranked up so the sealcoat dries properly but then have to open the garage door a few feet to vent the over spray and all the heat escapes. Oh well, it'll get done. I don't think I should be spraying that stuff with the heater on anyway...

[Alex Borshov]

Have you guys had a problem with sand paper gumming up when sanding shellac? The little gummy spots on the wood are about impossible to remove. My best luck has been to use 150 grit paper, instead of 220 like I wanted, and to blow the surface clean after each pass, but it's still not great. I'm using an electric sander. I'll try hand sanding in the morning but that's going to take a looong time. The shellac dried for at least a couple hours before I started sanding so I don't think that's the issue.