I got an apparently unused thread cutting attachment included in the deal when I bought my Unimat 3. Unfortunately, no 'guides' or 'jaws' (Emco's terminology) were included – I suspect the original owner never had any. Not much chance of coming across any, here in NZ.

I know this approach to thread cutting has a noble heritage, but the design of this particular contraption doesn't inspire much confidence. Can anyone report whether it's worth trying to use the thing – if only for 'fun'?

If it is, please could some kind person tell me the main dimensions of the 'guides' and 'jaws' (masters and followers), so I can make a few? I realise that I could design my own parts, but it might be nice to keep roughly to Emco's standards, in case any genuine ones come my way later.

Also, does anyone know anything useful about the change-wheel-based, hand-cranked threading set-up that Pro Machine Tools doesn't seem to have in stock?