Isolating a section of already-ballasted track?

[RobertInOntario]

Rob: you may have to use the cutters twice, once in each direction, to both get a smooth cut on both faces and to have a bit of a gap.
You will probably want to file the running surfaces afterwards, anyway.
Don't use them on anything other than rails or small copper wire. Guitar strings, switch machine rods will notch the blades.

Thanks, David -- will do. I've already tested them out on some scrap track and can't believe how easy they are to use, especially after hacking away with my Atlas saw for all these years. I wish I'd bought these cutters much sooner! At least I'll have them at hand if I ever get around to building any new layouts, which I keep thinking about.