Quote Originally Posted by m_c View Post
Realised earlier that I've actually got a GTN style in the lathe just now.
It's this one - https://www.shop-apt.co.uk/part-off-...2mm-shank.html
Tip to the back of the head is about 26mm. I only remembered after I'd turned the lathe off, and the parting tool was at a less than ideal angle to accurately measure.

I also measured a 26mm diameter WDN holder, and the tip to back of head is 21.1mm
Thanks. Hadnt seen your reply but APT believe it should fit so ive ordered one of these.