Wood – Storage Bench Possible with 3/4″ Plywood/MDF

I have used MDF for a number of furniture building applications. Shelving, cupboards, cabinets (body and doors).

1. It is easy to work into interesting shapes, you can cut curves using a jigsaw and sand it easily.
2. If you sand off any of the surface, and on the cut ends, you get a very different finish than on the front/back surfaces. If you want to get a smooth uniform finish I suggest using an undercoat of acrylic or PVA. If you are careful and get the undercoat right you can get a very smooth (almost plastic looking) finish.
3. Best to avoid damaging or removing the surface, as the surface is quite different to the inside and may contribute to the strength (not sure).
4. I usually sand over and round any exposed edges to prevent then from getting damaged. I always finish MDF with some kind of paint, so the texture differences are hidden.
5. MDF is very dimensionally stable, I have had no real issues with it changing size due to temperature or moisture
6. Basic MDF is not very good at handling high moisture levels. I always try and seal it as far as possible using a paint with relatively high moisture retardation (couple of coats of gloss paint for example). I have not so far experienced any serious moisture damage to my MDF even in places I have used it as an experiment in my kitchen where it is exposed to humidity (replacing chipboard which was being damaged by the humidity). However, it has only been a few years so I will see how it is in another 10.
7. Use exterior grade MDF if your application is likely to be exposed to high levels of moisture.
8. I often fix it with wood glue and dowels, but screws will work fine as long as you drill a pilot hole.
9. MDF is not as strong as plywood, if you are using it for shelving/load bearing you will have to increase the thickness compared to plywood or use some other method. For the sides of cabinets, etc, I have sometimes used two pieces attached face to face.
10. the dust from working it is a bit horrible, so wear as mask/use extraction

Overall, it has some advantages and some disadvantages. I think it is rarely the best material, but probably good enough for a number of furniture building applications. And for some things (like cutting into shapes with a jigsaw) it is very handy (no grain). I have not so far had any serious durability issues, but I do always take the above precautions.

The power tool you would use to take the board down would be a thickness planer:

It has an adjustable cutting head and you run the board through it in successive passes to shave off the surface.

However, unless you do a lot of rough lumbar milling or are into fine woodworking, it would probably be silly to buy one. Maybe you can rent / borrow?

Note that a thickness planer is good at making 2 faces parallel, but it won't be much help if the wood is also twisted or bent along its length. The twist will just follow through the planer and you will end up with a twisted board with 2 parallel (but not planar) faces.

Edit about the suitability of thickness planer:

Several people have pointed out that to use a thickness planer you are "supposed" to have one face flat already. I guess that's optimal but I have used a thickness planer many times to "save" cupped boards. If you have a great piece of wood, you might as well try something, right?

• Start with the convex side up, so that the board is stable against the base and doesn't rock.
• Work in small passes at the beginning. If you try to take too much off the planer will press down on the board and flatten it without really cutting.
• Once you have flattened the convex side you can alternate faces.