blueman wrote:
Speedy Jim writes:

If there are a lot of them to cut, one way is to
use a circ saw with a masonry (abrasive or diamond)
blade. You can mount a wooden guide strip to keep
the cut straight.


My main concern is precision and neatness of the cut rather than the
time it takes.

If so, would it be better to use a Dremel (with tile cutting bit) or
Circ saw (with masonry blade)?
(Assume in both cases I am using an edge guide to make the cut straight.)

blueman,

I've had good success using a 4" Makita offset grinder with a dry
cutting diamond blade. I have 2 different blades. One is serrated and
makes a little rougher cut than the finer blade. Someone mentioned the
masking tape along the cut line. That helps, as does steady hands and a
good eye, covered with safety glasses of course. An assistant holding
the shop vac nozzle right at the point where the grinder is kicking the
debris goes a long way towards dust removal. I've used a box fan in an
open window (blowing out) to help with the dust factor also.