I have a solid wood front door that's stained dark mahogany plus several coats of polyurethane.I now want to paint it (colour undecided yet).What prep. would I have to do for the paint to take and look good? Thanks !
It is up to yourself have much you wish to do. A perfectly acceptable finish can be obtained by sanding down the door first. If the existing coat is fairly smooth all you need do is sufficient for provide a key for your paint. But if the existing coat or lumpy full of brush hairs and stuff you may opt to be more thorough with the sanding.
After that whatever it says on the can. Probably 2 coats of decent paint.
You may, I have done so for an internal door not so long ago, but that was only because I was taking paint off to put stain/varnish on. Otherwise it is of questionable value. But if you feel enthusiastic ..... But for a painted door, i wouldn't.
I got meself a really nice little black n decker hand-size electric detail sander. it's shaped like an electric iron and is noisy as heck but really does a brill job. The shape means you can get into crevises easily.
I also have a hot air stripper, good for getting layers of paint off, but I think you'd find a sander does the job on your door so you can easily strip it down, then build up your varnish coats and sand down inbetween coats.
Hi
It's not so much the finish as the reasons to rub down with fine sand paper to form a KEY for the x2 under coats + further rub down then top coat.
HTH Tez