Amongst the things I need to get the new hopped-up TR1-engine working, is a means to re-surface the cylinder heads after welding them up. As I don't own a large surface grinder, a fly-cutter is the means to an end.
First up was a chunk of 110mm diameter tool-steel, that was squared up on both sides and then center-drilled.
The future-shaft was made to a hefty press-fit and then, as the thought of a roughly 5kg fly-cutter arbor flying off through the workshop gave me a "slightly" uneasy feeling in my stomach, I decided to additionally TIG-weld it.
Once it was welded up, it was put back in the lathe to turn it down to final dimensions and also decrease the amount of potential wobbles.
After some thinking, I decided to decrease the overall mass by milling both sides flat. (Which incidentially also made tapping for the set screws quite a lot easier.
The result is pretty acceptable, especially when considering that this was done on a flimsy RF-25 roundcolumn mill.