Use of MDF for painted plaques

[popssawdust]

MDF

I do a lot of plaque of various patterns, mostly from hardwood (oak, maple, ash etc.) I am wanting to expand into painted plaques and was wondering if MDF would be a good? What are the advantages or disadvantages over using soft woods like pine or poplar. Would I need to alter the blade selection and how does MDF effect the blades. I use FDUR for most of my cuttings.
thanks POPS

[dgman]

Hey POPS, welcome to the forum. MDF takes paint extremely well, but is not designed for outdoor use. It will quickly soak in moisture and puff up when exposed to moisture. MDF cuts very nicely with smooth edges but produces very fine dust, a dust mask is mandatory. I personally am not a fan of cutting MDF on the scroll saw, but I have seen some wonderful projects made from it.
MDF is made from wood chips and lots of chemicals and binders, so it will eat up you blades a lot faster, but I would use FD UR blades.
Good luck and let us know how it works for you.

[Forester]

I cut only MDF and treats it with a sealer to stop the paint sinking in.

[3_M]

Hi Pops,
The blade choice is just fine.
FD Mike

[JohnB]

G'day Pops,
I use a lot of MDF for puzzles and various things.
It cuts nicely, and is much stronger than solid timber at when thin items are to be cut.
It paints nicely and you can either do as Forester suggests use an undercoat/sealer prior to top coat or just put on two coats of colour. Water based acrylics work best for painting. Cut each coat of finish back with fine paper prior to applying the next coat.
Depending upon the quality of the board, there is no more inherent danger in cutting MDF than normal timber. In Australia there are strict guidelines on the amount of formaldehyde used in the glues. It is the same adhesive used to bond plywood so there is no difference in cutting ply and MDF. You can get it a number of formulations. Standard MDF for use in cabinets etc. MR MDF (Moisture Resistant) for use in bathrooms and wet areas and HMR MDF (High Moisture Resistant) for use in exterior applications and boats.

[cpowell]

I cut some MDF the other day. It was half inch (because it was free) and you are right; it cuts very nicely, very smooth cuts but it really hard on blades. I had cut it down to size on the table saw and was surprised at how fine the sawdust was. It actually was like dust it was so fine. Now I'm trying to think of what to do with the rest of it since it is so thick. Maybe bookends...

[jigsue]

Hi Pops

Almost everything I paint is made of MDF. A couple of coats of sander/sealer, with a rubdown after coat one or two base coats of paint (I, too, use acrylic). Much less preparation than with wood, no breakouts as with ply. Comes in lots of thicknesses and is cheap!

Gor for it
Sue

[tdub4ever]

Forester, do you use just a sanding sealer or.......? Don

[Forester]

Yes Don I use a MDF sealer.It works well.I only use MDF and love working with it.I have worked with pine,oak and beech for two many years in the furniture restoration and kitchen fitting.Like Sue said it cheap and the DIY shop is not far from me to get it.And with the help from Don I am enjoying working with it.