"Heath Robinson" is "Rube Goldberg" in British.Ah yes-- but does his humour travel, please? A bit like Gerard Hoffnung.
I have a parting blade holder that provides 5 degrees rake but also use a classic parting tool in a standard QT holder. To avoid grinding a top rake angle I place a suitable thick spacer under the tool front, presto structural rake without grinding.He had a thin piece of metal wedged under the cut off tool.
The lathe was probably a bit larger and more rigid than a model engineer's one.In The Home Shop Machinist magazine years ago there was an article from a Guy Who regularly parted off 11" and 18" bronze. A picture showed a piece of 11" being cut. He had a thin piece of metal wedged under the cut off tool. Not to burst anyone's bubble, including Mine.
Had a bit of trouble finding the Enots parting tool videos, so here is the one that compares tools:
And here is the one on grinding a parting tool:
In another video, I notice that he is using the insert tool type which I use. I have no trouble parting off with carbide inserts.
Jack, thank you for the comment, trouble was the lathe was stalling and the motor was still turning and screaming on the smallest pulley so I went to the next bigger pulley for more grip, catch 22, I realize its not the best setup with the holder hanging out in a little block clamped to a 0.500 post with very little support but this operation is just a one-time thing my normal course would be the cutoff saw, I just wanted to show how an old ancient tool holder can still do the job,I think your lathe would have had a much easier job parting that steel if you used the lowest ratio on your pulleys.