MDF Core

[Forrest747]

Went to buy the walls, interior and roof today and the company I went to had 4X10 only in 3/4 with MDF core. This sent off red alarms and flags in my brain dont buy it for teh exterior.
They had rustic alder and alder and cherry in 4X10 yet it was all MDF. I recall Madjack using a poplar core. I am willing to drive within 6 hours of Salt Lake to get my plywood. Any help or advice. thank you.

[Miriam C.]

Had no idea you coulld get MDF core anything. How scary is that?

[bve]

MDF Core for inside cabinets (inside a building) isn't too surprising.

Most people seem to recommend cabinet makers or 'real' hardware stores ie not the colorful big boxes for good quality oversize panels.

[kennyrayandersen]

:o Had no idea you coulld get MDF core anything. How scary is that?

yeah, I've used a ton of it -- especially for building speaker boxes. It works really nicely. But... I wouldn't use it for a teardrop exterior

[madjack]

MDF, stands for Medium Density Fiberboard...very stable product for cabinets and other interior project...DO NOT USE in an exterior situation as it will turn to mush when wet...I use a 13 ply, birch veneer over popular core ply(very stable) because it is available to me at reasonable prices through a cabinet shop...any multiple ply(9, 11, 13 ply) should be OK to use, especially is if it has a hardwood core...avoid plys that only have 5 or 7 (or 9 even) layers...try to avoid most Chi-plys as they tend to have voids, assorted nasties and some have problems with delamination...
madjack

p.s. MDO (Medium Density Overlay), is different from MDF...MDO is a hardwood ply with a waterproof covering used in the sign industry...usually, a very stable and HEAVY product which is excellent for exterior usage on tears which are going to be painted or covered in aluminum........MJ

[dwgriff1]

MDF core is done so the final board is solid 1/4" thick. Other ply that says it is 1/4 isn't. I used a lot of it for cabinet door panels.

Usually it has two good faces as well.

Madjack is right. Do not use it externally. And, except for door panels perhaps, I would not use it internally on a tear either, it is much to heavy.

dave

[wannabefree]

What Jack said!! MDF is like a sponge, but it never returns to its original dry shape if it gets wet. Get water in a pinhole and it will swell up like a wart on a boar. Don't use that stuff where there is any risk at all of it getting wet.