I tried printing a model for that used a pc4-m10 pneumatic connector and for some reason the model threads didn't work as expected.  

I make a lot of threaded models and models with critical dimensions, so I know my printer usually excels at this sort of task.  

So, I made my own model in Fusion and was disappointed when my threads didn't turn out much better.

In one of my previous jobs, I learned how to recognize different types of threads.  When I look at a pc4-m10 connector I noticed the threads didn't appear to be the same as other metric threads, after a little bit of work on Bing I found this reddit article that says the pc4-m10 is not a metric thread.  Anyways, after incorporating their suggestions into my model I was able to get a fitting to thread into my model without any post processing.  I remembered this community feed and hopefully this helps others with threaded models using the pc4-m10, also, the same applies to the pc4-m6.