How to create a threaded portion on a ball.

[tristan_luscombe]

Hi folks,

I have a question that seems like it should be simple but although I've been using Fusion quite a while I'm not an advanced user by any means. 
I have a student who wants to know how to add threads around the middle portion of a cricket ball so that two hemispherical covers can be screwed on to it. I'm sure this is ridiculously straightforward, but I've just not sure how to start threading something that isn't cylindrical!

Any help that anyone can give me is very much appreciated.

Thank you!

Tristan.

[Warmingup1953]

Cylinders inside the hemispheres should give you threadable entities.

Edit:...Oh and for our North American listeners......

[tristan_luscombe]

Brilliant, thank you! As a matter of interest, how would I create threads on the exterior of the ball itself?

[davebYYPCU]

Decorative?  

Can’t think of any useful real world application, maybe similar to a Cam Lock?

Sweep the thread profile on a trimmed coil “Path”.  Might need a Guide Rail.

Might help…

[tristan_luscombe]

Thanks for your suggestion! 👍 It's not decorative, it's to hold two thin hemispherical components on to the ball. 

[davebYYPCU]

This is normal process,

but your outside thread? Like to see that 

Might help...