David Weaver
If you recall from the buffing bar tests, I also had a very inky iron oxide bar that has no alumina in it. It was super fine but too slow to use by hand.

I tried that same bar on this wheel, and the buffer has enough power to use it and get very similar results.

BUT, the iron oxide in it in tiny particles makes for a very inky bar and everything is iron oxide red - your hands, the compound that's flung onto the iron, anything below the buffer, whatever you rest the bar on.

That said, it's a viable alternative to this if the bar is wrapped and used sparingly.

Another example of media that's just too slow to use by hand, but the buffing wheel can make it usable and use it to mimic an extremely crisp submicron edge without having to use a bonkers fine stone or slow regimen.