Making Raised Panel doors with MDF

[Craig D Peltier]

Anything I should know? Like does the bevel thats cut need to be filled with drywall compound or can it just be primered and sprayed?

The frame will be poplar or maybe even hard maple I have here.

Thanks

[Chris Padilla]

I've never cut a raised panel in MDF before but I have sealed freshly cut edges of MDF with spackle (dries faster than mud) to get a better painted surface.

[Jay Brewer]

I have built alot of MDF doors, and I always rub lightweight spackling compound on the exposed edges before sanding. It drys quick and gives a smoother finish with fewer coats of paint required especially if you are spraying the paint.

[fRED mCnEILL]

I made all my own moldings in the house from MDF and applied shellac as a primer. Zitzer has a brush applied shellac based primer that works fine.

Fred Mc

[Peter Quinn]

I have made MDF raised panels and MD Lite raised panels, I prefer the MD lite (tuppan ultralight is one brand). Mills better, weights less and its easier on the tools. I have never filled the milled profile with spackle. I have used shellac as a sealer and one or two coats of primer before spraying or painting as a sealer and filler. You will need to develop some method of sealing and filling that spongy grain that works for you. I suggest you raise a panel as a test piece and try a few different methods to see what works in your situation.

I am considering using a grain filler next time and cleaning it up with one pass through the shaper, maybe tinted shellac sealer and a light sand before assembly, not sure, but you have to do something. A fully finished sample board will help you through the process.

[frank shic]

i just use the BIN primer since i don't have the patience for the spackle. make sure you have awesome dust extraction. mdf leaves the stickiest dust around but you save a lot of time by not having to glue up boards to make the panel.

[Bruce Gray]

I'm in the middle of a large kitchen project with lots of MDF raised panels and poplar frames. I did a fair amount of experimenting when I started and here is what I settled on:
- Raise the MDF panel (in a router table)
- Fill with drywall compound (I prefer to thin the mud a little first)
- Sand
- Prime (spray) with Zinnser BIN primer (shellac base)
- Sand
- Assemble panel
- Prime whole panel with either the BIN primer or SherwinWilliams PrepRite oil primer.
- Sand
- Finish

BTW, I also glue the MDF panels in place. I know that's heresy, but MDF is pretty stable, and it makes for a much stronger door. I checked the MDF manufacurer's specs for moisture expansion and I also did my own controlled test of MDF for expansion in high humidity, which looked like it should be ok. So far, so good. I can supply my humidity expansion test results if anyone is interested.

Bruce

[Karl Brogger]

There is a specific MDF that works well. I can't remember the name though. Gold something. Goldboard? A shop I used to work at used it because the machined surfaces were super smooth.

[Brian Peters]

Glue sizing, Spackle, compound, thinned filler they all stink and none work well and all require a lot of EXTRA labor. You're all wasting your time! Buy ranger board, or the equivalent also called double-refined MDF. It is designed to be face machined. I pay about $38 a sheet for it, as apposed to $20 for standard MDF. And it's worth every penny. Machines/paints like real wood; it can even be turned on a lathe. Lastly the glue in it is less harmfull to your tooling which means it won't dull your tools so fast.

Bruce I can't imagine doing a whole kitchen filling with drywall compound, must have taken hours doing that.

Also other brands that machine pretty well, Extira and Medex (for exterior or damp/wet environments)

[Brian Peters]

Anything I should know? Like does the bevel thats cut need to be filled with drywall compound or can it just be primered and sprayed?

The frame will be poplar or maybe even hard maple I have here.

Thanks

Oh and go with the maple if you have it. Poplar is OK for building doors but it's not as stable as maple. I would recommend building most doors out of soft maple over poplar. Especially larger ones. Poplar is really only a good wood for moulding; I use soft maple for doors/face frame stock.

[David DeCristoforo]

MDF? Drywall mud??? I thought this was a woodworking forum...
I will say no more....

[Neal Clayton]

MDF? Drywall mud??? I thought this was a woodworking forum...
I will say no more....

here's a cellphone pic of a proper door from yesterday, maybe if we breath deep while counting to 10 and looking at it, it'll help with the urges

[frank shic]

craig, poplar with mdf will work fine for doors. i've even built doors completely out of mdf: rails, stiles and panels. the dust was fairly nasty but i used a mini cyclone which helped a great deal. i primed with BIN and didn't sand until after a second coat. i then painted with regular white latex and the doors (some of them measuring 4 feet high) have held up fine for the last two years.

[Per Swenson]

Chritsoforo is right,
This is a wood working forum.
But, and listen up Bin is not the solution.
If you must use shellac, it must be dewaxed.
Now zinsser offers seal coat.
Other wise you must make your own.

[Jim Crockett]

MDF? Drywall mud??? I thought this was a woodworking forum...
I will say no more....

And your point is???

Is not making raised panel doors woodworking? Is not MDF made from wood fiber? So why should questions regarding the above not be in a woodworking forum? I suppose only questions relating to "real" wood should be allowed - is that your contention? No plywood, no fiberboard, no mdf, etc. - and maybe no pine, no fir, only hardwoods?

JimC