Thread: Working with mdf

ahh and here are the fireplace pics and my really detailed shelf plans..

There are many ways to skin this cat.

When I have built with MDF I used mostly dado and rebate joints ... no nails or screws needed (except for the back, if you use one) and very strong. These days I wonder how I got by for so long without a dado blade.

You can rout a moulded edge onto MDF and get a pretty good finish. Needs only a light sand ... or even square edges off the saw are quickly sanded if you have a nice sharp TCT blade on the table saw.

MDF takes almost any finish really well. I used sanding sealer and coloured N/C lacquer to finish MDF jobs, because sanding sealer and lacquer are so easy to apply and so forgiving, but it is not as tough as two-pack. If you go for the two-pack, they usually have a matching sanding sealer, which is recommended because it is so easy to sand smooth.

I usually glue and screw man-made board. Depending on the job I sometimes cut a dado, which makes it easier to align and gives a stronger joint. But you need to be accurate with your dados. If you want you can bang in a couple of brads to hold it while you screw it together. If you are going to have adjustable shelving, drill your shelf pin holes before assembly.

Standard automotive quick dry enamels, acrylics and two pacs are all pretty good with MDF. Just treat it like a car panel that you can't get water on!

Hi Timbo123.
I don't mean to throw a bucket of cold water over your wood heater installation, which looks very neat. However I am somewhat puzzled as to why you would want to enclose a wood heater like that?
I had a wood heater here in chilly southern Tasmania that was installed into an old brick fireplace. It was insulated on all sides except the front like yours. The house was always cold unless you were huddled up close to the heater. Figured out most of the heat was just going up the flue.
Anyway, pulled that heater out and put a newer freestanding one in the middle of the room with the flue exposed and was completely astounded by the difference it made. A really toasty warm house that uses about a quarter of the firewood the old set up did. Blocked up the hole in the old brick chimney and use that space to store firewood now. Wish I'd done it years ago.
I know Bendigo gets pretty cold too, which is why I mention this.
Maybe you have a heatpump or other means of heating and just want the wood heater as a visual , snuggle up around the fire sort of thing which is fine. It sure is nice to sit and watch a fire.
Just my two bobs worth mate.
As for your actual question regarding mdf....well that's another story. I thought the stuff was banned in some countries due to it's toxic makeup?
I will shut up now.