Butress thread call out

[ronw06770]

Hello all.
I have a special Butress cut thread in a cap (female internal) to make that matches a plastic bottle (male exterrnal).
My problem is which profile is the default? 5, 7, 9 and is this a programable geometry on a 4+ axis machine or turning center?
The mating bottle only gives a nominal thread dia and a 5 pitch. thread inclusive angle is 735 degrees. Yhis will give me about 2.3 full threads.
Any help or wxperience with this?
Thanks, Ron

 

[CheckerHater]

Ron,
Unfortunately several manufacturers do not bother following standards and invent their own plastic threads as they go.
Modified Buttress thread is common on plastic parts and “modified” is the operative word. It will be different from standard Buttress thread you can find in Machinery’s Handbook.
Does the manufacturer of the bottle provide any clues, as any other dimensions, or call-outs like “NECK FINISH” or “FINISH” accompanied with some letters and/or numbers?