15-30k RPM 7x12 Mini Lathe

That's clever, but keep in mind that it's often done the other way around, using the lathe's bull gear as a fixed-value indexer. If your bull gear has an appropriate number of teeth you usually can get a variety of symmetrical steps around a circle.

I've used my South Bend to do that kind of thing several times. I hold the Dremel, or my old industrial-grade B&D die grinder, mounted in my milling attachment, although it could be rigged in the toolpost.

The clever Brit hobbyists have sometimes modified their lathes with a worm gear driving the bull gear to get pretty versatile indexing.

Yep, kinda the backwards method, but quick as far as not needing to fabricate a proper sturdy holder for the Dremel handpiece.

Access to gears on a mini lathe (and numerous other models) is limited to one small gear at the left end of the spindle.

For utilizing the spindle for a 3-position indexing task, a surface of the jaws of the 3-jaw chuck should be adequate for equal spacing, or 4-jaw chuck for 2 or 4 positions.

As Jim W mentioned a while ago, a hex nut is sometimes a convenient divider reference.

Yeah, there have been a number of clever ideas used to provide indexing on a a lathe spindle. One interesting one I saw used a set of three or four fine-toothed gears mounted on a faceplate, allowing a wide range of symmetrical divisions, located with a spring-loaded pin that was mounted on the headstock.

At that point it starts to become a gymnastic exercise, but it works, and it costs a lot less than the regular solutions.

I haven't seen a method using the gears and faceplate arrangement, but I've seen a simple method mentioned at least several times, which is to make up an incremental scale to glue around the circumference of a chuck.. definitely a cheap method and good n'uff for certain projects.