Michael Black wrote in
xample.org:

Module boxes can be made out of copper circuit board, but getting them
nice requires some effort.


I came close to solving that, a small cheap Proxxon circular saw with a
carbide blade. The edge was awesome, so clean the FR4 was almost polished,
but it's extremely dangerous because the blade binds against the FR4, so this
method is ONLY safe to trim small flexible strips. But as a finish after
using a hacksaw to do the grunt work, it would work. A hollow-sided carbide
blade would be great, but I've never seen one, and dread to think what it
would cost!