Painting MDF

[Ken Shoemaker]

I'm planning on making my own moulding, for a rental I'm buying, out of MDF. I can cut them on the router table. My question is, after running them thru the router, a slightly rough finish is left. Has anyone ever done this, and what was your finishing schedule. I'm going to paint them white when is finished.

Thanks in advance for your help.

Ken

[Derek Gilmer]

Two coats of kilz seals it up pretty good for mdf "end grain" like you are running into. Light sanding between coats to smooth it out.

I've also used a 50/50 mix of wood glue and water painted on to seal it up. That took 4 coats to get a good finish though.

[Prashun Patel]

Sand to ~150-220 and then use Zinsser Sealcoat or BIN primer. Quick sand again, and it's ready to paint.

I would consider wood for the baseboards in a rental unit though. They get abused over the years - nay - months.

For crown, I prefer MDF because it's flexible. and can be machined easier at the coped corners with a file or rasp.

[Ken Shoemaker]

Good Input guys!!! Wood for the bases and Kilz for the primer. Got it, Thanks, Ken

[Prashun Patel]

Ken with due respect to the others, kill can stink for a while and it's really overkill in this case. Personally I think a shellac based primer is a less smelly soln

[Derek Gilmer]

Ken with due respect to the others, kill can stink for a while and it's really overkill in this case. Personally I think a shellac based primer is a less smelly soln

Having done a little bit of handyman work for a friend who owns rent houses I'd offer that in a rental house/duplex the smell of paint may be better than the other smells. Like a long term air freshener for the place.

[Howard Acheson]

Let me go in a slightly different direction. You write that you are planning to make you own molding using a router. Let me warn you that you will be creating clouds of dust. I would strongly suggest you work outside otherwise you will be cleaning up forever. And be sure you have and use a good dust filter respirator.

[Ken Shoemaker]

Thanks for the reminder Howard. I have a 4" pipe from my router table to the cyclone. Dust collection is pretty good, but I think I'll revisit the respirator. I think the cartrages might need changed.

Thanks, Ken

[Jerome Hanby]

All my MDF pieces get a coat of shellac. I think it makes the MDF surface a little tougher and helps seal in the formaldehyde (sp?) that can out gas over time. I never really noted the exact sanding schedule, I just get it smooth, but Prashun's sounds about right.

Ken with due respect to the others, kill can stink for a while and it's really overkill in this case. Personally I think a shellac based primer is a less smelly soln

[Derek Gilmer]

Thanks for the reminder Howard. I have a 4" pipe from my router table to the cyclone. Dust collection is pretty good, but I think I'll revisit the respirator. I think the cartrages might need changed.

Thanks, Ken

Not sure what you have but I picked up a 3m 7500 for turning/sanding on the lathe and that thing works great!

[Matt Meiser]

You can also paint the raw edges with glue size made from diluted white or yellow glue. I've don that on smaller painted MDF pieces and its worked very well.