I did a search here but nothing useful came up. It's really a pretty basic thing, so hopefully someone has come up with a quick solution around here. I suspect some of the open source PCB layout tools like kicad might be able to do what I need, so that's why I put it in here to start...
All I need is to generate a template/pattern for a bunch of regularly spaced holes (maybe 30-35) that I want to drill in a piece of scrap plastic. I think they're going to be on about 0.07" center, and maybe .02" diameter holes - but I won't be 100% sure till I place the template in the project space and verify it. They need to pass 30ga insulated wire, which has a slight tolerance so I may need to adjust after generating a test template. If they'd been 0.1" center, I could have used a piece of perfboard, but noooooo...
Yeah, I could lay it out with a ruler, but then if I calculated wrong with my initial estimate, I'll have to do it all over again. Faster if there's something semi-automated so I can print out updates quickly.