I have a part that requires 1 M10X1.0 6H thread. We are using a 9.558mm pre-drill and a cold-forming tap. We have a go/no-go gage to check the pitch, but we are interested in measuring the ID of the threads after tapping. I cannot find any information in the Machinery's Handbook on this thread. Can anyone tell me what size pin gages we should use to check this diameter? Thanks!

M10x1 6H Metric fine thread - Internal
Pitch - 1mm
Tol. - 6H
Major dia.min. - 10.000
pitch dia. min 9.350, max 9.500
Minor dia. min 8.917, max 9.153
I think you are looking for the minor dia.
Hope this helps - Juergenwt

Thank you juergenwt. Where is this kind of information found? Thanks again!

http://www.beuth.de/cmd;jsessionid=0D7C7837C7DBF19101C70ADD2F31CC14.1?level=tpl-home&languageid=en
The above link opens the English version of the home page for: Beuth Verlag GMBH Berlin, Germany. You can order directly or download.
You need pocketbook Nr. 45 - Threads. DIN - ISO 13
All DIN - ISO thread specifications are in that book.
ISO is for the most part a copy of DIN - Deutsches Institut fuer Normung (German institute for standards.
I am also giving you a few other leads:
http://www.gewinde-normen.de/en/iso-fine-thread.html
http://mdmetric.com/techindex.htm
If you need more help - pls. post it here and I will be glad to help you (if I can).

Make one minor diameter plug and check after threading (Tapping).