Painting Over Varnished Coated Doors

[Metal Head]

Hi,

I just checked out if there had been any previous questions via the search facility but I was surprised to see there wasn't.

However, I have 2 interior doors that are varnished but I want to put on a coat or two of acrylic paint. I was wondering if I have to sand back to the bare wood and then prime/undercoat it prior to putting on two top coats?

Or do I only have to rub the surface with some 240 grit paper to take the shine off?

Btw, the last time I painted a door I made the mistake of using an orbital sander that left little circles on the surface. I thought the paint would cover them up easily but it took a few coats and then there were still patches were you could still see them. Thus is this when you would use one of those 1/3 sheet sanders instead?

Does paying out mega bucks on a top sander - lets say a festool just to prep surfaces for household painting - over kill and a waste of $$$? I presume most guys here who have top brand named sanders use them on your wooden items where the finish is important.

Thanking those in advance of their replies.

Cheers
MH

[Barry_White]

I would tend to remove the varnish with a liquid paint stripper first.

[Big Shed]

If the varnished surface is sound and the adhesion is still good, I would just sand to a dull finish, then undercoat and 2 topcoats.
I think stripping back to bare timber is overkill if the existing surface is sound, but if it is loose and flaking by all means sand back to bare timber.

I would probably use the 1/3 sheet sander, but have also used ROS for this, it really depends on what grit you are using and how hard/soft the varnish coat is.

As a mtter of interest, wat acrylic are you thinking of using? Bear in mind that a lot of acrylics are very soft, particularly in summer (thermoplastic).

My son has used Dulux Aquanamel Satin with good results on internal doors.

[bob w]

Hi MH
Duralex Paints make a product called Bleed Seal which will do the job. A light sand one coat and then top coat. Check here
www.duralexpaints.com.au

Cheers
Bob

[Pusser]

I believe Zinser shellac based primer/undercoat will go straight over the varnish and take whatever topcoate you want to apply. It will also effectively cover the colour and drys quickly.

[echnidna]

You only need to sand back with 120 grit paper for house paints.
Read the instructions on your paint can, most will work without any primer over the varnished surface