MDF vs Blockboard Cab

[TDSmith]

I'd go with Medium Density Fiberboard. It machines well, glues well, and is fairly stable on all axis. The cabinet makers at the Smithsonian use it for just about everything because they can hold sub mm tolerances on even large cases. It's best not to think of MDF as a wood product. It is one, but from an engineering point of view it resembles fiber reinforced plastic more than it resembles a wood product. For your use case that's a positive.

MDF does deteriorate with moisture. A sealer or a few of coats of polyurethane paint/varnish inside and out would be a good idea.

Block board might start with the stability of plywood, but over time the natural wood blocks inside will expand and contract and cause it to delaminate. Then you're left with a floppy walled box. Not good.

The natural wood options sound interesting. Dense woods like teak in thick boards? Done right they would look and sound fantastic.

Stay far, far away from particle board, aka Low Density Fiberboard. That stuff is heavy, weak, and falls apart with moisture. It's best use is a $20 kid's IKEA nightstand.

 

[La Faro]

I figure after sealing the ends, using rattle can car paints on MDF

 

[Redbrangus]

There's no need to seal the 'ends'...there is no end grain like on a piece of wood. You can treat the cut ends just the same as the other faces. (IME) Take some pics, please. Good luck with it.

 

[MIMike]

I was going to say the same, but call it chipboard (which I think is the old name in the UK for it)

chipboard (over here anyway) is like cardboard. Used for ridged mailing envelopes, the stiff backing sheet for padded paper, etc. you also see vinyl covered chipboard that they make those cheap acoustic guitar cases out of.

 

[La Faro]

Seems UK still calls it particle board chipboard

Chipboard flooring from the UK

 

[seamonkey]

There's no need to seal the 'ends'...there is no end grain like on a piece of wood. You can treat the cut ends just the same as the other faces. (IME) Take some pics, please. Good luck with it.

MDF actually does have grain.


It's a good idea to seal the ends and edges. Normal PVA glue works great.

 

[seamonkey]

Oriented Strand Board (OSB) is sometimes called chip board around here.
There is some very high quality OSB you can get for furniture making but not available to the general public.
OSB is used in a lot of house construction, floors, i-beam, Water resistant MDF is showing up more and more as carpenters can build more things with it. Not a bad idea for home owners to buy it as you never know what you'll build.
There are many different densities of MDF for the trades. Higher pressed , or Higher resin is more weight.

 

[La Faro]

I'm sealing the ends, so that I can get a nice finish when I apply the spray cans. I've used MDF for lots of things and sanding cut ends to a nice finish for paint doesn't work well. Sealing then sanding does.

I'll be using roundover bits, on all edges, so I'll seal all those too.

 

[Redbrangus]

MDF actually does have grain.


It's a good idea to seal the ends and edges. Normal PVA glue works great.

OK, I stand corrected; structurally, I guess there is a 'grain'. But I've never detected any difference in the way a cut edge takes a coating as compared to the face of the 'board'. I have to confess that I haven't built a box out of MDF in about 20 years, but I don't really have anything against it...other than it's obvious disadvantages, I mean. As to the acoustic advantage, AFAIK, almost all the audiophile-type stereo speakers are MDF with nice veneers on them.

 

[Bermuda Ron]

I am not an expert, but I worked in the furniture industry for some time. Vietnam exports a lot of bamboo products for furniture and flooring. Glued up stock or laminate might fit the bill. About three times stronger than most hardwoods, and more dimensionally stable in your climate. Tien Bo Bamboo and Plywood might be able to help you. (I have no affiliation or financial interest).

 

[La Faro]

I'm a fan of bamboo, but I don't see it here apart from chopping boards. Not even laminate flooring. I have an investigate, because a bamboo cab seems cool to me.

I'm less concerned about MDF a the humidity here. My Prosonus Eris 8 studio monitors are over 5 years old now. Took the back off on last week and the inside is exposed MDF and the speakers are ported. Plus they are powered speakers so they get a little internal heating when they are on. So they must be dealing with humidity fluctuations well. Although I'll probably seal my cab for peace of mind