Spiral groove in curved surface

[bolsover]

I'm looking for some advice on how to model a spiral groove on a curved surface.

The finished item is a clock fusee. the metal blank is generally per the image below



The curve on the surface is of a fixed radius (2 11/16") . The groove needs to be 12 TPI.

I understand how to model a thread form - but only on a simple cylinder.

Any suggestions welcome.

Thanks, db

 

[DavidJ]

This file may give some ideas - it probably needs work to be anything like what you are trying to achieve. Basic idea is to create some geometry that leads to an edge, that you can project into a 3d sketch to define your path for a sweep. I've left the temporary geometry suppressed, ultimately you might delete it when happy with the part.

 

[idslk]

...Don't change "Sketch<3>" into any other geometry than a circle

 

[AlexB]

This file may give some ideas - it probably needs work to be anything like what you are trying to achieve. Basic idea is to create some geometry that leads to an edge, that you can project into a 3d sketch to define your path for a sweep. I've left the temporary geometry suppressed, ultimately you might delete it when happy with the part.

That's very smart, adding a temporary helical feature to create a spiral vertex to use as a reference line. Nice one, can use that technique on other problems.

 

[DavidJ]

It wasn't my idea, the basic approach was shown on the forum years ago.

IDSLK is correct - it is ridiculously fussy about the profile sketch - anything other than a circle may either fail entirely, or show some weird artefacts as the sweep introduces twist into the sweeping profile.

 

[bolsover]

Thank you so much.

The example is just perfect - problem solved.

d