Building/Gluing/Painting MDF?

[indytims]

Yup! I would love to hear all your ideas/suggestions for putting together MDF buildings and then painting them!

 

I've googled a bit and seen 1000 different suggestions to the point I am not sure what would be best, so I'd love to hear what you've experienced works best for -you-.

 

For gluing the parts together - superglue? Wood glue? Elmers? Someone mentioned using Modpodge (which I have), But I am keen to hear what works really well!

 

For painting, I've read that using basic normal primer is bad, because the mdf will 'soak it up'. Not only have I read that this could alter the entire surface of the piece I'm working with, but it also is a waste of primer. I've read where some people use a 'lacquer' to coat the mdf first, let it dry completely, THEN prime it?

 

I've never worked with MDF before, so any thoughts/suggestions would be greatly appreciated! :)

 

-Tim

[Raindog]

Maya Cast says to enamel prime them first.

[Justjokin]

Most All of this is home depot mdf trim and panels.  Glued mostly with zap-a-gap, but I could have used superglue, or construction adhesive.   All before painting.

 

 

 

 

 

 

This was primered black with a mix of random plastic friendly spraypaints, because that's what I had.  I then dry brushed some metalic that I also found in a small can at Home Depot.  

 

The floor is granny grid which you can find at fabric and craft stores.  I don't know what they call it, but it's used for macrame or crossstitch or some such.

 

My favorite detail here is a cast of the bottom of an oreo cookie tray... guess which one...   also glued with zap-a-gap.

[Justjokin]

I'm going to spray paint airbrush glowing blue and yellow lines on the outside of these an make them work with Infinity.  Just got some new plasticraft stairs to help. 

[ChaosGerbil]

Never had a problem priming MDF. I usually use $4 Rustoleum 2x coverage flat black primer.

 

A word of warning on glue, especially for gluing sand or flock down. While not nearly as prone to it as cardboard, a large area of white glue can warp the base board and cause it to curl up a little, enough so it isn't flush with the table. My solution is to use weights like full soda cans to press down on a few key areas. Other people put glue on the other side to try to cancel out the bending, I have not had luck with that.

 

On gluing in general, here's my go-to method. Put a thin layer of superglue down on either side (either Gorilla brand or Krazy brush on) and then if there is any gap put a small peice of green stuff or dab of white glue in the middle. Press down firmly. With white glue you don't have to press down as long as for superglue alone, the white glue's moisture accelerates the setting of the superglue and the whole thing becomes tacky instead of slippery. Use a scrap, or a tool to wipe away excess. Another trick is Insta-Set accelerator. Using these methods has helped me with dozens of terrain pieces and thousands of conversions.

This will work fine for MDF. Admittedly for terrain I enjoy the fun of hot gluing for fast results, but then I reinforce with white glue and sand so a hot day doesn't wipe out any work. Hot glue can look really amateur if you're not careful.

[Lange]

MDF requires shellac to seal raw edges, otherwise it soaks up paint. Lasercut MDF doesn't always need this because the cutting process usually seals it, but I would recommend shellac anyway. After shellac, sand smooth with 220 or 400 grit sandpaper and glue/prime. You can use superglue or wood glue to assemble. If you're going to apply sand or flock with white glue, use shellac and primer on all sides to prevent warping.

[Justjokin]

MDF requires shellac to seal raw edges, otherwise it soaks up paint. 

 

I didn't seem to have too much trouble with this, but I certainly see how it could be an issue.