help with metric threads

[thrawn7977]

Hi, I need to make some threads in a back shell connector.
the threads i need help with are m31x1-6h class 2b threads.
I am not sure how to make these in pro/e i know i have used
a helical sweep before for the threads but I am not sure
about making internal threads. i am not sure what surface
to select but even more i am not suer of the dimensions to
use for that thread. i am guessing the m31 is the dia in mm
and the x1 i think is how many threads per mm i think the
6h has something to do with the thread depth but am not
sure and i am not sure how to enter all this in pro/e.
thanks

 

[design-engine]

helical sweep. You have length of thread ... pitch.... and thread shape.

 

[dr_gallup]

Unless you absolutely have to show the thread form (for a molded plastic part for instance), it is normal practice to just use a cosmetic thread feature. All the pertinent data is contained in the thread parameters & shown as a note on the drawing.

Metric threads conform to international standards, get them, read them, understand them. Machinery's Handbook is one place to start. M31 is your major diameter, 1 is the pitch (mm per thread, not threads per mm) 6h is the fit, same as standard for metric fits & limits for holes and shafts (external thread since "h" is not capitalized). I think class 2b is a mistake here as that applies to inch thread classes.

If you really want to waste a lot of CPU cycles, you can create the thread form in exquisite detail with helical sweeps.

 

[thrawn7977]

thanks for the quick replies. I got it to work i went ahead
and made it a helical sweep. I found an old model i had
that had the matching threads to it so i used that and the
advice given here as a guide. the mil spec does say class
2b it is for a glenair backshell for a d38999 connector.

 

[Mindripper]

It sounds like you do indeed need the threads modeled for makng a molded part. You can find thread form information in Machinery Handbook and a variety of other sources. Although it's unlikely you will the specific dimensions for a thread that's nominally 31mm major diameter and 1mm pitch, you can use the dimensions for an M6 x 1 thread (a standard 1mm pitch thread) and simply add 25mm to the diameters.

 

[Mindripper]

BTW: '6h' is the metric version of a thread class, as '2B' is the inch version of a thread class for a female thread.