Call out for a pattern of concentric holes

[Azeemsha]

I am having a pattern of two concentric holes on both the faces of a C channel, these holes are drilled together in one go. The pattern has four sets of these two holes ( total 4x2=8 ). How to properly show this in drawing. I am using iso - gps

 

[greenimi]

Could you, please provide a "fake" drawing for clarification
Maybe use position with CZ or maybe with SIM......
Or even CZ CZ could be used

 

[Azeemsha]

Thanks for your reply, i am attaching a ref drawing. I want to show that each hole of the bolt hole pattern on one face of the C channel and other face is drilled together so that concentricity between the drilled holes are with in a specified tolerance. Hope the question is clear now.

 

[greenimi]

You might be able to use ISO 5458:2018 for reference.
I think SZ CZ or CZ CZ with position could be used.
No need for coaxiality....I think.

 

[Doug Hunter]

I would just add a note under the GD&T frame reading "THROUGH 2 WALLS", or something like that.

 

[MaxSka9]

You could use CZ CZ, or sim, or simply treat them as 4 continuous holes with CT and Envelope.( See attached option B) Or a combination of some of these options, it all depends on what function the holes will serve.