Designing thread for plastic bottle.

[Yort1]

Hello, I'm trying to design threads for a plastic bottle with a 24/400 neck finish. I have the specs for "SP-400 Finish for Plastic Bottles" which indicates a standard pitch of 8 threads per inch, but what I'm getting hung up on is the spec for the helix angle (2.56). Given the pitch and the thread diameter, doesn't the helix angle become reference?

 

[patprimmer]

Pitch and diameter locks in helix angle, presuming a single start thread

Regards
Pat
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[Yort1]

Okay that's what I thought. Thanks!