Ok, am I nuts?

Sitting at lunch we started talking bikes, as we do some times.

Fixed gear came up, and the question also came up, will a track cog fit on a threaded hub intended for a "freewheel"?

And if so, is it possible to build a fixie by brazing the cog to the hub? We are talking about a cheap steel hub.

Let the name calling begin.

(edit) Yes I intend to remove the axles and bearings for the brazing.