I have an 11 inch swing Harrison gap bed lathe of 1960's origin here in the
UK. I use it for "bits and bobs" and cannot call myself a turner by any
stretch of the imagination. Parting off has always been a bit of a
nightmare for me with rough finishes and sometimes broken tools. I have
only ever bought brazed tip tools, as damage is not too costly

I now find myself in need of drilling 16 mm holes in 3 1/2 inch round bar
mild steel, and then parting off to make washers about 1/4 inch tick with
good finishes both sides. I need to make quite a few, perhaps 12 of them.
Is it worth buying a replaceable tip tool for this? I have no brazed tip
tools that have the reach to part something this thick. Any tips and what
tools do you recommend, as if I buy something it might as well be of a make
that I can stick with for other tools. Nothing too exotic though please,
and remember I am in the UK, so an Internationally available make please.
Thanks for reading.