On Wed, 30 Aug 2017 17:57:06 -0500, "Dave M"
wrote:

Anyone have experience in accurately cutting 1/8" thick acrylic Plexiglas
(Perspex) for LED displays?

I need to make filters for some panel meters of my own design, but am having
trouble finding off-the-shelf bezels and filters of the sizes I need.
Before everyone tells me that there are cheap Chinese panel meters available
on the web, I already know about them. My meters are for a unique
application and the available digital panel meters can't be modified to fill
my needs. The display is the really unique part, and I need to make my own
filters for the displays. I need 3 different sizes; 1.25" x 2.5". 2.75" x 5"
and 4" x 5".

I've thought about using a table saw with a cabinet-grade finishing blade.
That's possible, but somewhat dangerous due to the small size of the
filters.

That should be no problem on a table saw. Make sure to use a zero
clearance insert. Cut into the short-side sized strips with a fence
than chop those up with a miter gauge with a stop. Perfectly safe.

Also thought about hot wire cutting. That's quite possible, relatively safe
(just have to keep fingers off the hot wire). Might be hard to keep the wire
taut enough to make straight cuts, and guiding the plastic through the wire
or the wire through the plastic.
Also thought about cutting on a drill press or milling machine. Again, a
bit dangerous due to the small size of the work. Clamping would be tricky.

Any suggestions as to a good, safe approach to cutting the plastic?

Your first thought should work just fine as long as you take
reasonable care.