# MDF finish?



## L Town Graphics (May 24, 2012)

I have read many different places that people prefer MDF over plywood for the dimensional stability and it's longevity. What do you guys and gals use for finishing it? I have read before that an oil base primer is better than water base. I have also seen the edge strips (not exactly sure what they are called). I'm considering purchasing a piece for sign making but also wanted to gather some info first. Thanks in advance!


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## Cherryville Chuck (Sep 28, 2010)

MDF never moves, it's basically a mix of very fine sawdust and resin. I would primer it first and the best stuff, in my opinion, is Zinsser Bulls Eye 1-2-3. You can follow up with oil or water finish. There are 3 grades of mdf that I know of. Lite where weight is important, regular, and a finish grade which is the one that cabinet doors would be made from. The finish grade finishes better. All of them are for interior use only. MDF does not tolerate water very well.
There are a numer of edge treatments available from channels that slip over the edges, vinyl that has a tongue that presses into a slot, to hot melt or glue on melamine and wood veneer banding. You can also make a solid wood border around the mdf and because mdf is so stable, you don't have to worry about the joints getting pushed apart from humidity changes.


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## DaninVan (Jan 1, 2012)

Dan; if you want to prime it anyway, why not simply buy the prefinished panels to start with? PJ White Hardwoods Ltd.
Huge labour saving!
Cheers,
-Dan


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## bobj3 (Jan 17, 2006)

Hi

I love to use MDF but once you open it up you must sand it and seal it, I use shellac spray....MDF is like a sponge once you open it up.

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## Bradleytavares (Feb 25, 2012)

I do quite a bit of work in MDF and have had positive results. It doesn't move and accepts all types of joinery well. When you screw it together it's important to pre drill and use a dw type of screw thread for wood. Wide threads. If pneumatic nailed, don't nail to close togerter or to close to edge as it tends to seperate. The type I use is the high density that is designed for laminating plastics for countertops. It's identifyiable by the size, 49" x 97", one inch over sized. As far as finishing I use Deft spray for shop furniature, shelving, doors and storage items after it's been sanded lightly with 100 grit. It gives and interesting industerial look that is commented on and copied by others. Even thought about producing furniature and cabinets with this look as the industrial look is favored by many nuevo designers and owners. Edge treatments used are a simple 1/8" roundover to ease the corner. Looks sharp.


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