On 31/08/2017 08:57, 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.
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?

Dave M



As others have said, use a CO2 laser. About 40 watts or higher should do
the job. They cost from about $4000 upwards, and are so useful that many
hobbyists and clubs have them. It leaves a nice smooth edge on acrylic.
Acrylic is one of the materials that it can cut well and safely. (e.g.
Don't ask them to cut PVC, it makes acidic fumes that attack the
mechanism of the machine and poison the bystanders.)