Oh you are going to love this.
to recap, cutting a taper, toolpost in usual position, large end of taper at chuck end, cutting right to left.
as you know, I stripped and refitted the top slide.
tried just now with a new piece of steel.
same thing, cutting barrel shaped.
then I tried something silly.
I moved the topslide assembly to the rear of the cross slide, put a different tool in, swung the topslide round a few degrees , ran the lathe in reverse and cut on the back of the taper.
and it cut a WASP WAISTED taper
so I've got a topslide that likes to turn right. (sounds like a Dr Who story).
at least it'll fit without a wobble
if the tool was being pushed away from the cut as the topslide extended you would think the cut would be the same no matter what side it was cutting.
I don't think I want to turn anymore tapers.
cheers
A thoroughly confused Roy