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MG MGB Technical - Course thread tap and die

I have set of the standard british taps and dies used on MGs, but I need a set of the course threads that BMC used for tapping castings. What are these? (I know I should know! Is it UNC??). Thanks James.
James Eastwood

James - If you are working on MGBs, the taps and dies you need are American national fine (or SAE). The course thread equivalent is national course. Cheers - Dave
David DuBois

Actually, they are Unified National Coarse and Unified National Fine. US,UK, and Canada adopted the Unified National system after WW II so they could have standard components among the allied nations. The MG uses the UNF threads in most steel parts and UNC threads in most aluminum parts.

Les Bengtson

UNC in cast iron as well, generally.
Dave O'Neill2


Many thanks for the prompt reply, I shall get some on order. This forum never ceases to amaze me, 3 answers from round the world in under 24 hours, it's one of the great pleasures of owenership of this marque.

Thanks again, James
James Eastwood

Try for Bolts, Nuts, Taps and Dies
Geoff F
Geoff Farthing

This thread was discussed on 06/12/2012

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