Epoxy and 2k onto MDF?

[julianf]

I want to get some small shaped MDF parts to look like the high gloss white plastic that was so frequently used in 1970s design.

I don't know if the job below is actually plastic, but it's indicative of the style that I'm going for -

Epoxy primer seems to stick to anything. Can I just do the parts in that and then go for top coat as per normal?

Thank you.

 

[James1979]

I painted some wooden panels that go round the lower half of our walls (No idea what the proper name is) that I made from MDF and a router. When I asked how best to paint them, I was told Acrylic Primer then whatever on top. Worked really well. Acrylic primer is not cheap. Also, its hard to get out of driveways when you drop the bucket

 

[mike os]

Have a chat with symphony coatings or morrel's

 

[julianf]

I should have said - these are indoor parts - abrasion resistance required, but no weather tolerance.

 

[mike os]

As above, its what they do

 

[norsa]

Absolutely you can. The MDF soaks up the first coat but then subsequent coats hold out and can be flatted and top coated.
Nick

 

[Dcal]

Barr coat (it's the only thing it any use for) 2K primer then 2K top coat.

 

[julianf]

Barr coat (it's the only thing it any use for) 2K primer then 2K top coat.

Do you mean use the epoxy primer AS a barr coat, or some other product prior to the epoxy?

I googled it, and upol do some isolator thing, but, to confirm, can i go straight to the mdf with the lechler epoxy that i have currently (ie avoid going shopping again!)

Thank you.

 

[Dcal]

"Barr Coat" is a single pack sealer that’s mostly shellac (same stuff as knotting solution) it seals the mdf and stops the subsequent coats sinking in.
Then any good primer to fill out any defects, sand back and I'd suggest a 2K top coat for the look, resistance to damage, and long service life.

 

[Dcal]

Epoxy primer will certainly do the job, however it might swell the MDF if it's been machined or you sanded through the outer layer.
Once the epoxy cures you can do pretty much whatever you want as long as you don‘t sand through to the MDF again.
If you do, reapply, let it cure and re-sand.

I think epoxy would be an excellent choice.

 

[Al Strachan]

Never used epoxy on mdf but it sounds good. I’ve used Upol P88 before to seal the edges and it’s sandable in an hour and really effective for getting a smooth flat edge in one thick coat.

 

[norsa]

Interesting that Barcoat works on MDF. Not heard of that one but it has to have some use as it's not good for car bodywork. Barcoat is an alcohol based sealer/isolated which does the job but doesn't cure so leads to issues later in life. I'll accept it works on MDF but as said, so long as the MDF is fully covered, you're on a winner.

 

[a111r]

I painted some wooden panels that go round the lower half of our walls (No idea what the proper name is) that I made from MDF and a router. When I asked how best to paint them, I was told Acrylic Primer then whatever on top. Worked really well. Acrylic primer is not cheap. Also, its hard to get out of driveways when you drop the bucket

I'd agree with all that apart from 'not cheap' , as Leyland or Screwfix brand is around £15/L.

I sprayed some MDF and thought that the overspray, for water-based, would very soon vanish from cobble sets and the spare car door.
But no! Impressive that it's there after a year...

 

[Turbo]

I wouldn't have thought that epoxy would be the best stuff for spraying wood. It is really for painting metal and sealing it from rusting.

What I would use is standard 2k filler primer, it will be a lot cheaper than epoxy plus easier to sand. If you want to get that plastic coated effect you will need to sand it to a very smooth finish.

Last year I sprayed a set of mudguards for a tub trap we were building in our Mens Shed. They were made from plywood bent around a former. I applied several layers of filler primer & dry sanded it completely flat, finishing with P400 on a DA sander. It was then top coated with 2k black gloss.

The finish I achieved even impressed me, it had the 'plastic coated' look you talk about, perfectly smooth & very shiny! The guys in the shed wouldn't believe that the mudguards were wooden because the finish was so smooth!

 

[ajlelectronics]

Lechler* epoxy primer works out far cheaper than 2k, doesn't contain isocyanates and is superior in every way. Solvent content is 10% just like 2K so little opportunity to attack the "wood". Brush painting could be done without thinning anyway.

* No idea how Jotun compares price wise as I don't use it.

 

[Dcal]

Lechler* epoxy primer works out far cheaper than 2k, doesn't contain isocyanates and is superior in every way. Solvent content is 10% just like 2K so little opportunity to attack the "wood". Brush painting could be done without thinning anyway.

* No idea how Jotun compares price wise as I don't use it.

Welcome back aj, it's been a while and I hope you are keeping well.
I agree wit what you are saying about epoxy, except it is harder to sand than 2K primer.
As @julianf already has the epoxy I would go with that.

 

[RonA]

I’ve just purchased some what is described as low viscosity epoxy resin for wood (not cheap). I bought it to waterproof the cut edges of some buffalo board I am using for floorboards on my resto project.
RonA