Painting mdf

[Imwalkin]

I have a project that is made out of MDF that I want to paint with automotive paint. What it the process.
I was thinking off sanding and going right on with the prime but I worry about it just absorbing the primer.

Any thoughts or other ideas?

 

[adam728]

A high build primer will fill in all the voids and give you a good base for a finish. Cut edges will need some sort of filler before the primer, I've used automotive glazing putty.

 

[ilovevocs]

A high build primer will fill in all the voids and give you a good base for a finish. Cut edges will need some sort of filler before the primer, I've used automotive glazing putty.

Same here. Mine were all interior installations. I am assuming this is as well.

 

[cyato]

If you have access to paint guns and an air compressor, I would suggest using a polyester high build primer like Evercoat Featherfill G2 or PCL Polyprimer. If you have seams between different pieces of MDF, I would brush polyester resin (catalyzed hot) on the seams and joints, then wipe off the excess with a paper towel. No need to apply resin to the whole thing! Make sure to wipe off the excess. I wouldn't apply any fillers until after the first coat of primer. (I've primed and painted a lot of MDF.) The first coat of primer will be absorbed like a sponge on the cut ends and will be rough. Just sand (80 or 150 grit) and re-prime. Sand with 220 and 320/400 and it will be ready for darker colored automotive paint. Lighter colors and silvers will require a coat of sealer and/or sanding to 600 grit (or maybe even 800 grit). Good luck!

 

[Imwalkin]

It will have open edges. On the corners. That are rounded off. I think I will fill the filler a try.
Thanks for the replies.

 

[rjwilliams]

Drywall mud worked like a champ for me. I got that idea from Fine Homebuilding or something.

 

[JonBoehman]

What I do with the edges or tooled sections of mdf is to mix a little bit of Titebond 2 and water and roll it on those portions of the board. Let it dry, then prime and paint without it soaking into the wood.

 

[Regnar]

I use Spakling on the machined edges before prime and paint. Goes on quick and is easy to sand off. I have made hundreds of names for kids rooms and done probably 30 themed rooms with MDF. I hate the **** but does put out a nice product.

 

[niget2002]

I use spakling too on MDF.

I've also used bondo when I had some laying around.

 

[brianh]

I use shellac sanding sealer it hardens the fibers for a smoother sanding finish. dries quick sands easy and is relatively cheap.