@efrench
Thanks, that's an excellent link. I spent ages trying to find something like that on Aliexpress, but failed. I was probably not using the correct search terms.
I did a quick test using a 3/16 carbide endmill on a scrap piece of cold rolled steel held in the vice at 45 degrees, and the result was OK. The metal wasn't square to the Y axis but as the picture shows the lower of the two lines was around the correct width.
Many Thanks
Best Regards
picclock