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ChrisA Edwards
08-07-2019, 10:25 AM
My next project is to build two large built in cabinet/drawer units in our master bedroom. The wife wants them pained white, so I though I'd use MDF for the drawer fronts and doors.
The larger of the two will house a 65" TV and be about 11'L x by 9'H x 2'D.

I've just got a new Shaper, so I plan on doing raised panel doors and details on the drawer fronts.

For the drawer bodies and face frames, I'll most likely use Cherry with Dove Tail joints. For the sides, shelves and internal structure, I planned on using finish plywood, although that's going to be painted as well.

Are there different grades of MDF? ​i'm only familiar with MDF from the big box stores.

Should I skip the MDF and use solid wood for the drawer fronts and doors even though they will be painted?

Thanks

Frank Pratt
08-07-2019, 11:09 AM
The quality of MDF varies widely. The stuff at the big box stores is the worst that I've ever used. I can't recall what brands are good and bad, but in general, you want to avoid ultra light MDF unless you absolutely need to save the weight. It has a very soft core, delaminates easily, and absorbs water readily. Standard MDF ranges in quality from that of the ultra light to some that is fairly good. Medex is the only MDF I use anymore. It is water resistant, slightly heavier & more expensive than regular MDF. The main things are that it is stronger & the core doesn't disintegrate if you look at it wrong and it is not bothered nearly as much by moisture.

You'll need to go to a proper lumber supplier to get the Medex or better quality standard MDF.

Mark Hockenberg
08-07-2019, 11:19 AM
Hi Chris,

I agree with Frank and would avoid box store MDF. I don't use any MDF/melamine/hardwood from the box store that's going into furniture or cabinets any more. Too many issues with quality.

You may want to consider poplar for the doors and drawer fronts. I prefer poplar over MDF for a paint-grade fininsh. It machines nicely and sands up very smooth. When painted, I get a better result than painting MDF.

Congrats on the new shaper!

Cheers,
Mark

Bill White
08-07-2019, 12:17 PM
I have used Extera (brand name) exterior grade MDF for columns on a home. Painted of course. Has held up well over 10 years.
Used the off cuts for numerous shop projects too.
Stuff is HEAVY, but is very robust.
Machines well, and doesn't fuzz up on the edges either.
Might be a choice for your project.

Mike Henderson
08-07-2019, 1:26 PM
Hi Chris,

I agree with Frank and would avoid box store MDF. I don't use any MDF/melamine/hardwood from the box store that's going into furniture or cabinets any more. Too many issues with quality.

You may want to consider poplar for the doors and drawer fronts. I prefer poplar over MDF for a paint-grade fininsh. It machines nicely and sands up very smooth. When painted, I get a better result than painting MDF.

Congrats on the new shaper!

Cheers,
Mark

I agree with using poplar - unless it for outside. Also, MDF can be hard on blades if you use a lot of it.

Mike

Steve Jenkins
08-07-2019, 2:15 PM
I use plum creek mdf for paint grade. It is a bit denser and the face finish is harder

Yonak Hawkins
08-07-2019, 4:18 PM
...you want to avoid ultra light MDF unless you absolutely need to save the weight. It has a very soft core, delaminates easily, and absorbs water readily.

Frank, I won't disagree with your assertion that Ultralight MDF de-laminates if you drop it on the corner or, otherwise, stress it beyond limitation but, I use it regularly for a standard job and have gone through a couple dozen or so bundles in the last 12 years. I've never noticed that it has a soft core unless you consider everything except the pressed surface as the core. This is true with all MDF I'm familiar with. I will, however, assert exception that it absorbs water regularly, however. I have done three tests, over the years, for just this issue and I've never found it to become deformed due to water. I have used both Trupan and Masisa brand Ultralight MDF and, while I'm sure I have tested Trupan, I'm not certain I have tested the Masisa for water exposure.

The attached photos show one test : before the test, while soaking, immediately after soaking overnight, half way dried and completely dry.

414002 414003 414004 414005 414006 414007

You'll notice that the MDF pieces look virtually the same before and after the water test.

All this said, I will agree that Ultralight is not meant for structural applications and should be used when weight is an issue but, from my experience, the common notion that Ultralight MDF disintegrates when exposed to water is a myth.

Frank Pratt
08-07-2019, 4:27 PM
Yonak, I'm sure there are brands of ultra light MDF that are better than others. Most of the MDF trim that I've seen is made from the light MDF & is terrible stuff. Just look at the corners of baseboard & door casings in a house with pets or kids. That stuff wears away in no time. And once the paint is worn off the surface, it sucks up water like a sponge.

The good stuff can be had from a wholesale supplier, but the retail outlets have to sell the very cheapest stuff they can get because that is what every other retailer sells & they have to compete. And that's the stuff to avoid for sure.

Mel Fulks
08-07-2019, 5:53 PM
I like the Truepan ultra lite . Smooth and solid, paints up well.

Mike Cutler
08-07-2019, 6:47 PM
I would just use solid wood for the whole project. Then again I detest MDF in any form.
As for "grades". I can't speak to that as I don't use it. I do know that it comes in different densities, weight, for the same size sheet.
Again though, I can't stand the stuff, so I am definitely no expert.

Jamie Buxton
08-08-2019, 9:47 AM
For painted raised panel doors, I'd use lumber for the frame -- poplar most likely -- but MDF can be okay for the panel. Before assembly, I'd prime the part of the panel where the core is exposed by the raising cut. Glue the panel into the frame on the back side, where there is no primer. Make the frame wide enough that the hinges fasten to it, not overhanging on to the panel area. I dunno what you mean by "details on the drawer fronts", so I can't make construction recommendations.

Mark e Kessler
08-08-2019, 10:43 AM
I would use either a paint grade Poplar, maple or pattern grade Mahogany, the only thing I use MDF anymore for is veneer layups.

Mark

Edwin Santos
08-08-2019, 11:39 PM
I too think it would be preferable to use a paint grade solid wood for the project.

However in answer to your question about grades of MDF, yes my supplier carries three grades - Ultralight, regular and Plum Creek which they call the caviar of MDF. I have used Plum Creek more than a few times and it is much denser (and heavier) than the other types of MDF. Where it excels is very clean routed edges (no fuzz). However, MDF is a necessary evil and I would avoid it for your project. Save it for jigs, substrates and stuff like that.

Interesting note, even the "regular" MDF from a professional supplier is miles ahead of the junk MDF the home centers stock, at least in my experience.

Frank Pratt
08-09-2019, 9:49 AM
I have used Plum Creek & it is much harder and more moisture resistant than the cheap stuff.

Erik Loza
08-09-2019, 11:36 AM
I have used Extera (brand name) exterior grade MDF for columns on a home..

When I was in the A&D millwork industry, we experimented briefly with Tricoya acetylated MDF panels. It's the real deal as far as moisture resistance. We couldn't do much with it since it would require a CNC router to process and our product line was cladding done primarily through a moulder but the parent company, Accoya, has a GREAT reputation for exterior-grade softwoods. Looks like they have some dealers up in the Northeast.

https://tricoya.com/

Erik

Thomas C Barron
09-08-2019, 10:23 AM
If you want to get technical, there is only one grade of MDF. There might be different manufactures that use a different glue that works better.

I’m guessing that you might be confusing the different grades of fiberboard.

LDF light density fiberboard
MDF is medium fiberboard
HDF is high density fiberboard

Peter Kelly
09-09-2019, 8:08 PM
If you want to get technical, there is only one grade of MDF. There might be different manufactures that use a different glue that works better.

I’m guessing that you might be confusing the different grades of fiberboard.

LDF light density fiberboard
MDF is medium fiberboard
HDF is high density fiberboardThat would refer to densities, rather than grading. Differing grades of MDF boards are based on how refined the particles are, what type of glue, formaldehyde present, moisture content, performance characteristics etc. E.g.: Plum Creek Super Refined (interior only) is great stuff but not in the same league as Mediate Tricoya (waterproof exterior).

Robert Engel
09-10-2019, 10:10 AM
MDF mills extremely well and paints well so it is a good material for drawer fronts & door panels. But here's the "but"...... 3/4 MDF for a raised panels can add a lot of weight to a larger door, so you need to consider that in the construction and hardware.

Drawers are traditionally made with a secondary wood, and for good reason. The more expensive primary wood is for the "show". Its your decision, but its a philosophical thing with me, so thought I'd mention it.