alphatec":12rxdqda said:
Hi n0legs
Thanks for your reply.
I have a spray booth, we resprayed telephone casings for BT in the past so would be pretty confident on the safety side.
If it is not to much bother could you tell me the process particularly which primer you used to seal the mdf,
I see people saying car paint cracks over time because it is not flexible enough for this use, is this your own experience?
Thanks
Terry
Well with a booth and previous experience you're on the right track. Just make sure you're safety's up to scratch :wink:
For the edges and any routed profiles on MDF I sand like a mad man to get them as smooth and as closed in as much as possible. I find a brushed on coat of primer over these edges helps to get them sealed up well before I start finishing properly. I get that sanded back with 320 grit, then get into the priming and finish coats.
I usually use Max Meyer 3011 high Build primer.
http://refinishsystems.com/max-meyer/ma ... ler-primer
Or a lesonal equivalent.
Most of the stuff I use is either Lesonal or Max Meyer, in a 2k system.
If I use a water based top coat, this will be applied over a 2k primer, I clear coat with Max Meyer 0300.
I've tried most of the brands, Kapci, PPK, Glasurit to name a few, but I've found the Max Meyer and Lesonal to be the best for my purposes. Take the 0300 lacquer kit, that's 7.5 L, it covers brilliant and the kit lasts forever. Over bare wood it's 2 coats and it's done.
You can buy cheaper but you'll apply twice as much. The HS stuff just covers and covers. I did a little painting a few weeks ago and I used about 500-600ml and covered approx 2 sqm, twice (2 coats) and I ain't liberal with it either.
I've painted stuff that's ended up in my bathroom, bedrooms and other areas and to be honest I haven't had any cracking of the finish. The clear coat I've used over natural wood hasn't suffered any problems either.
The only issue I have found is the primer taking 4 hours to dry/harden. I always let my finishes air dry, I can bake them if I want but have found (to my cost) that the baking temp for these 2K products (upwards of 40C) causes the wood to release trapped gases/air and cause tiny bubbles in the paint film. This has had to then be refinished, I should have listened to people who knew better #-o
For me it's the cost of the stuff, cheap. I can use and apply it properly and safely. It's as tough as iron. It can be repaired easily. The choice of colours and finish, satin, matt etc. But most of all it looks great, no brush marks, no runs and ease of use.
Shane":12rxdqda said:
All I would warn against with mdf is any filled screw holes will swell, no matter how carefully you fill and whichever paint you use, so think carefully about fixing positions
Try sealing the fixing hole before filling it.
Drill, countersink, fit screw and then I use a little 2k clear lacquer (really a tiny amount 20-30mls or less if I can get away with it) and a cheap airfix/artist brush. I paint the bare MDF around the fixings, get a couple of coats on it in quick succession. Let it dry then fill with car body filler. To be honest I've found water and pva/pva a waste of time and I avoid all water based fillers.
Day after painting. waiting to fully harden before polishing.
Pain in the a$re to paint
Clear coats during application
Mums table after nine coats, apply and flat, apply and flat, apply and flat and polish. It's too shiny to photograph.
