External NPT Threads

[qdraftz]

I am trying to put external NPT threads on a 12" cylinder, however I read that fusion does not offer NPT thread size and that most people create custom threads. Any help would be greatly appreciated! 

https://a360.co/4cHyu3d  cylinder design

[DarthBane55 · Accepted solution]

I threadmill NPT regularly, not sure where you saw it can't do it.

Just model a cone with the correct size for the minor diameter, including the taper, and pick it in your threadmill operation.  Or model the major diameter and then add the diameter pitch compensation in the passes tab.

[qdraftz]

@DarthBane55 that did the trick! When I modeled the taper it wouldn't let me select the face that was tapered and apply threads to it. But when I made the face flat it allowed me to. 

Thanks! 

[DarthBane55]

hmmmm, you need to model the taper, otherwise your threadmill will go up straight.  The threadmill path needs to follow the NPT taper angle.

[qdraftz]

We haven't started machining yet, but in the simulation it looks like it follows the taper angle set in the passes tab even though the wall is straight on my model. 

[DarthBane55]

Do you have options I don't maybe?  See what I have below, there is no taper angle field!