Now, I am faced with what seems to be a very large task of actually painting
all of the window frames and jambs. There are a lot of them (40+). The
walls and floors are finished , so I can't make a mess. And, I need the
finished painting to be high quality, i.e., smooth, free of brush or
rollermarks, etc.

In my house, we've pulled up a lot of the carpet to expose the wood
floors underneith, and discovered that while the floors are in
*almost* perfect condition, they are covered in tiny flecks of paint
where someone decided to use a sprayer on the walls. I have the
distinct impression that the person who had the carpet laid did so
because of the paint that got on the flooring.

In short, spraying the trim inside your house without a lot of
practice and nearly perfect masking is just begging for trouble. When
you start atomizing paint and spewing it out of a gun, it gets
everywhere- unless you really know what you are doing.

As an alternative, you could remove the windows and then spray them
outside, or you could do it with a brush. If you've got a good brush
and good paint, it's unlikely you're going to see a noticable
difference between the sprayed finish and the brushed one. Prime the
windows, then sand the primer flat, prime again and sand again, and
then apply your paint in even strokes that start at a seam or an edge,
and continue until the next seam or the far edge. Things only start
looking a little dumpy when you try to overlap brushstrokes midway.
Then you get the bristles of the brush pushing into the paint you've
already applied and causing imperfections.

It seems to me that my best approach would be to mask off each window and
door - masking a foot or so of the wall around each unit. Then, with the
right spray equipment, I might be able to spray each unit fairly rapidly.
My concern is overspray - I can't mess up the paint on surrounding walls,
floors, or ceilings.

Overspray is a problem, but that is the least of them, IMO. when you
start spraying, you're likely to end up with a small cloud of fine
paint particles that drift to the floor, the walls, and anything else
that air can get to. If you do spray, get some of those plastic tarps
and tape them to everything. Make sure the tape is secure and has no
little bubbles in it. If you leave a small gap (a bump in the tape,
for instance) you're likely to find that you've got a fan-shaped
cloudy looking area of paint on whatever you were trying to mask.
(another one of those things in the DAMKIHT file) Sprayer messes are
a heck of a lot harder to clean off than drips, BTW.

If it were my project, I'd either use a brush, or see how much a good
painter would charge to professionally do it. The cost of the sprayer
is likely to be almost as much as just hiring someone who can do it
for you.

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