I would use a spray paint in a semi-gloss. It need not be a precise match

I used regular wall paint to paint my registers. At first they looked OK, at
best. After a few years they looked crummy and made the rooms look old. I
bought new grilles. The difference is like day and night, although the new
registers are white and the walls are of-white.

--
Walter
www.rationality.net
-
"tacker" wrote in message
oups.com...
We are having a room with high walls repainted in a deep color. The
same wall has a typical return-air grille (24 x 24") with adjustable
vanes that has the usual factory-baked enamel, off-white color. We
wish to repaint the grille, so that it blends into the wall color,
rather than standing out in stark contrast.

It would seem that using an enamel or gloss paint is necessary, so the
grille may be cleaned periodically. Would it be best to use a primer?
Should the grille be sanded first? To achieve a smooth finish, should
the grille be sprayed?

What is the best way to do this job?

Any advice appreciated.

Thanks.