Pianting routed MDF doors.

I have always either used a glue size or drywall spackle. Both seemed to work well. MDF is like a sponge anything wet and it will swell so you have to seal it somehow. I suppose there wouldn’t be anything wrong with using shellac to seal the profiles and give them a quick touch up sanding afterwards. The shellac will dry quickly and provide a good seal.

-- Save lives, ease suffering, reduce morbidity and mortality, stomp out pestilence and disease, postpone the inevitable, and fake compassion. The Paramedics Creed

I’ve never NOT had to sand after primer on any wood (or MDF). There are always whiskers, even with shellac or lacquer and they have to be cut off before the next step. No exceptions. If anyone has a primer that eliminates this step, I hope they share it.

Yep, i’d use the shellac as a sanding sealer.

-- jay, www.allaboutastro.com

Thanks for the tips but honestly half the issue is the Co I used to make the doors. There are tool marks throughout the panel and the corners look like a 5 year old cut them. Some are round, some are square and some are almost right.

The routed portions must have been done with a dull tool as there is just too much raised fuzz. I took a razor blade and scraped all the sections by hand before priming the rest. Honestly the Zissner oil based did a worse job then the water base. Sherwin williams bare wood did the best and was the easiest to finish sand.

It was something I didn’t want to do but I just sanded for hours and got it done. They look ok but the worsed is the corners have some rough edge which to me is a sign of a bad job which sucks after all the work on them.

I had ordered from Barker before and the doors were simply wiped offed, primed and painted so I know it isn’t the MDF or me. Oh well live an learn, next time Barker!