flat pattern from helical sweep (simple archimedes screw)

[RonaldKetel]

Hi, 

I need to create a flat pattern from a simple helical flat screw. Can anybody help?!

I use creo parametric 2.0 including sheetmetal.

[StephenW]

Sheetmetal won't help you here. Sheetmetal will give you flat patterns for press brake operations with a straight bends. Your part requires tooling.

You should look in the surface flatten. Maybe something like this: https://community.ptc.com/t5/Creo-Modeling-Questions/Flatten/m-p/361522#M91385

[KenFarley]

Exactly what you said. I had to make a surface exactly like this to build a dust collection cyclone, and the only way to get a flat pattern was to use the surface flattening. It worked out pretty well, too. I'd imagine it would also be possible to create the flat pattern using equations, too.

[BHOoi]

The best way to illustrate is by example. See the attached files, creo2 file included. Thanks

[RonaldKetel]

Thanks for your example.

I thought that the flat would be an open ring shape, meaning that both outer and inner curves would be arcs, with a certain radius. However the curves appeared to be (sort of) ellipses. Can that be the case or did something go wrong in the definition of the flatten quilt operation?

Thanks.

[BHOoi]

In that example, I modeled the helical shape with 360 deg turn. The inner/outer perimeter length is thus definitely more that  the perimeter of a planar circle with a same diameter. When the helical shape is flatten, it won't be a circular to preserve its true/same length ! Makes sense?

I have changed the same example so the helical sweep is below 360 and you can see the flatten shape is almost circular. Note that the flatten geometry won't be a true circular shape as it is in fact a project/wrap geometry, i.e. spline more likely. Hope this helps.