Thread Classifications - External or internal threads - Class 1 or Class 4 - Pitch?



Hey everyone!!!

A new problem. Is there a web site or a book that will easily explain the differences in thread classification.
Example external or internal threads that are classified with a class 1 or class 4.

Does this have to do with the tolerance or the pitch?

second thought I think this classifacation is for pin gages?
Am I right on this???
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Bill Ryan - 2007

I use the Machinery's Handbook almost exclusively for thread classifications. ASME also has some books available.

Pin gages use an "X, Y, Z" format for classification, I believe.



Hi Connie - "Everything you wanted to know about fasteners but were afraid to ask" is available from the Industrial Fasteners Institute - 1717 E. 9th Street - Cleveland, Ohio 44114-2879 in two massive manuals at about $100.00 each (one for standard - one for metric). Other contacts for them: Phone (216) 241-1482 Fax: (216) 241-5901 E-mail: [email protected] Internet:

Hope this helps.



Thanks dave

Hi Dave,
Thanks for your help. I'm sure this will be very helpful if not for now it sure will later!!
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