Great Kim you found a picture
In your ad that is a tap wrench used many of them in my day
I don't know why you keep say 'Blacksmith' ??
NO not a Blacksmith's die could they have them yes, but more likely a F & T
Your ad also says 'Machinist & Steam fitters' now that's where I fit in
TPI is relevant, very much so on which job it is
Yes of course one item was made by different manufactures nothing new in that
There is lot of different 'thread chasers' out there not used by blacksmiths But fitter & turners
Looks like we are touching the "expert" subject
Ian