Hi , today I read an article about building cabinets with MDF that are going to be painted, that came out a few months ago in a mag called "Built Ins"
They reccommend using all (except draw carcasses) MDF 3/4 standard density. As far as the edge grain are concerned use drywall compound and then sand so paint wont soak into end grain much.
IM going to build a built in that needs to be painted a smooth white.Shelves on top an 4 draws below with pocket doors in center.Piece is 102 wide by 94 tall.Ive read to sand to scuff up a bit with either 220 or 150 and then seal it with a non water based sealer and then first coat of painy non water based preferrably shelac or oil based.
What do you think of using all MDF so the surfaces will remain the same for paint. I read that 28 inch should be max span for 3/4 mdf.I will not have any spans further than that. There will be several shelves, if I do use MDF for shelves is it a must to edge band with maybe 1/4 inch hardwood for stability? Like I said I think only two spans are 28 or 29 and the rest are like 16 inches.
I think the top and back I will use ply.You wont see the top after done since it will going to ceiling minus 1 inch, but yet it will be strong.
Im aware of MDF cracking with screws and the joints best suited for MDF.

Thanks again

PS Im going to add a pdf to this shortly.