Ways to Make Slots in Sheet Metal or Plastic
I've searched for ways to make slots in sheet metal or plastic and haven't come up with anything new. I currently use a drill press to drill the end holes, and a rotary cutoff tool (much like a Dremel) to cut out the space between them. It's not a very precise method. I've also tried an air-powered nibbler, but it isn't very precise, either.
I know slots can be milled or laser-cut (but I don't have a mill or a laser cutter), or even done in a drill press using a milling vise.
I've searched the fabrication forum, and I come up with references to DIN slots and CF slots and slot-load, but nothing new on making slots in sheet metal or plastic.
Does anyone know a slick, low-budget way to make slots?
(I've asked this same question in my worklog, and I'll crosspost any answers I get.)