Hi all,
For those of yoiu who are interested I have just downloaded a programme from threading specialists Vargus. It is a free download and is a superb programme with a whole host of threads covered. It displays the preffered No of passes for a given thread for, Radial,Flank and modified flank in feed or you can specify the amount of passes you want and it will give all the relevant info. Brilliant.
Raymond.