OK IN MY OTHER THREAD I HAVE MENTIONED THIS......
I HAVE CONSTRUCTED A MDF SUBWOOFER ENCLOSURE AND I NEED TO PAINT THE SUCKER.....
I WOULD LIKE TO GET SOME INDEPTH HOW-TO'S ETHER POSTS OR LINKS TO WEBSITES......
I have a friend who is a cabinate maker and he advises mixing white carpenters glue with water, paint the mdf and let it dry. Then paint with whatever paint you desire. You can experiment with the proportion. This seems to work well and it seals the end grain of the mdf which can become feathery.
First, we're right here, no need to shout. Secondly, I'm not speaking from experience, just from what I've read about MDF in woodworking forums. (My more active hobby)
I don't know about mixing wood glue with paint, that just sounds odd, but I would definately recommend priming it with at least two coats of primer, and figure on at least two coats of paint. MDF sucks up any finish like you wouldn't believe. Also, depending on where you're located, you could try talking to people at a local paint store or, if you're feeling masochistic, you could try your local Home Depot/Lowes and see if they have a clue. (Not too likely, if you ask me)
Good luck, and let us know if you need more help!
P.S. - If you're looking for other opinions on painting or woodworking, check out:
As the other folks said, the main issue with MDF is that it needs to be sealed well because of its absorbative nature. Using primer will work, but will require quite a few coats before it'll be even.
Sanding sealer has worked well for me - two coats usually seals the box completely and primer goes on quite evenly over it (it is just a form of polyurethane after all). There is some info on different types of sealers at:
Also, head over to WoodWeb.com and search the Finishing knowledge base and Finishing forum for "mdf" and you'll find some good information on working with the stuff. The site is aimed at professionals so much of the specific paint/spraying recommendations don't apply, but the general info is good.
If you paint it with the so called 'boat paint' used for polyester sailboats and speedboats this will result in a nice piano-look finish. Another advantage is this paint is extremely durable and gives good protection against scratching, fluids and so on.
Only keep in mind it will cost a bit more than 'ordinary'.
If you want to seal MDF dont use paint...PVA(wood glue!) works ok but it isnt water proof so the MDF can still absorb water.
I have found(thru diy car audio)that fibreglass resin is the best perminate sealer/water proofer for MDF, paint the bare cut ends first with a brush wait till it dries sand back, then use a spray gun to coat the whole thing, two coats is plenty(can use a brush...but will involve lots of sanding to get smooth eg. no brush marks!)
The resin offers excelent adheasion for paint too, just remember wear a resiprator and clean out the spray gun when in between coats!!!(acetone)
Ps, if using spray gun for resin try to get a gun with a 1.8mm+ nozzle(its a enamel paint gun, not a acrylic one)prefably a gravity fed gun(over head paint pot)
Hmm...that's exactly what I want on my system...I'm all ears. Sanding, primer (?), what is required?? I'm building a full-range system for a business project (Marketing) and need a demo system in two weeks. I'm using my BOSE spatial receiver for the amp. and a four driver full-range system with a quarter fold wave that exits through a port on the back. I'm just picking up ideas and parts now...my largest concern is the painting...what should I do to get that piano finish or, atleast a good looking finish?
One of my friends coated his subwoofer with quite a few layers of sanding sealer with some light sanding in between, he then took it to the local "panelbeater" where it was sprayed in much the same fashion a car would be sprayed ...
The result - Very close to the Wilson Gloss finish of Wilson Audio ....