Whitworth pipe thread drawing callout?

[Burunduk]

What's the right way to call out an ISO 228-1 internal thread of class B tolerance on a drawing?
Is it the same way as a metric thread?

For example, a typical callout for a metric M10 thread is: " M10 X 1.5-6H "
where 1.5 is the pitch and 6H is the tolerance class.

Would it be for Whitworth something like
" G1/8 X 0.907-B " ?

Thanks

 

[3DDave]

As far as I can tell, one simply specifies the size as G1/8 and only specify tolerance class for ISO 228-1 external threads.

I would expect to use a flag note or "PER ISO 228-1" next to the thread callout to indicate the thread specification; In the US the thread specification is encoded as part of the thread callout (UN, UNC, UNF, UNJ, et al.)

 

[Burunduk]

Thank you, 3DDave.

 

[rothers]

From ISO-228-1

 

[Burunduk]

rothers,
Thank you for that reference.
Am I correct thinking that on the drawing view where you show and specify the threaded feature you only include the "(c) individual item block" in the callout?