Cog removal from bare hub success story

I had a very old ratty cog on a rather nice old maillard high flange track hub that was stuck tight. I got the lockring off, but made the schoolboy error of taking the wheel apart with the cog on it. Everything I read seemed pretty gloomy gettin it off, but i managed to get it off without soiling the hub too much by filing two flats onto the 'blank' area between the hub body and the freewheel threads, which I clamped in my machine vice to hold it, then removed the cog with a chain whip and huge bar. Then I filed off the marks made by jaws of the vice on the flats, and sanded n polished them until they were the same finish as the rest of the hub - they just look like part of the hub.

chuffed.

epic win, seeing as that is actually pretty much impossible!

Didn't think about partially building the wheel back up?

Not too difficult.
Just take a rim (preferably an older one) and 3 spokes & nipples, no matter what length.
Lace up the hub / spokes / rim (no matter what pattern, but best is to spread the spokes evenly at the whole circumference.
Doesn't matter that you have a full wheel, spokes tensioned, wheel straigntened and aligned. The 3 spokes and the other parts are usually strong enough to take the force necessary to remove the freewheel of sprocket.

For the DIY amongst us:
When I worked for "quite a big Japanese bike component manufacturer", we had some thick steel plates with 1 large hole and 28, 32 or 36 pins of approx 2mm around it.
Steel plate in the vice, hub on the steel pins and the work could be started...