[drphoto]

What's a good sealer for MDF? I don't need flawless results, as I plan to topcoat with something like auto undercoat. I'm making simple baffles for OB subs. (GR servos)

thanks.

[mcgsxr]

Standard paint primer has worked fine for me, for prepping for black truck bed liner finishes I have used in the past.

It is really only the end "grain" that you need to focus on, the rest is simple to paint over in my experience.

[Watson]

Virtually any sealer works with MDF, because it's so porous. It'll take anything. I use old dewaxed shellac (stuff that's too old for use in finishing).

[dwarfed centipede]

I used valspar spray primer.  It worked great on the flat surfaces, but you need 2 coats on the cut edges.