How can I create this shape in OnShape?

neil_ramsay

I'm trying to create this shape in OnShape. It's a 2mm diam hexagon around an 18mm diam circle rotated several times (number of times is irrelevant). Obviously, coming from Solidworks, I'm having a bit of a difficult time figuring this out. Solidworks, it was simple. Sweep around a circle with a rotation set. Done.

Here... I can't rotate a sweep. I've seen a bunch of things using additional functions with spiral curves and the like, but I can't figure out how to get the spiral to look... well... like this. It always looks more like a phone cord than a twisted sweep, so I'm not grasping it.

Rotated straight line is cake. But I can't get THIS shape.

Hints? Ideas?

MichaelPascoe

Hey @neil_ramsay, try the Loft feature, but it might be a bit tough. Or, you could use some custom features to achieve this. 

One way would be to use @Konstantin_Sh's custom feature Contour Spiral, then use a Circular feature pattern and apply per instance, like this. There is probably a twisted sweep custom feature, but I'm not sure where.

https://cad.onshape.com/documents/2a44a246d2e5dc0c8017a0c3/w/b4ad96fcd9e075efb78f5248/e/3eb5387f3c2ccb...

neil_ramsay

A clever solution. Wildly complicated, but clever!

My only concern with this as a solution is that it doesn't allow adjustable rotations. You get a set number from what I can see, and that's it. If you adjust the contour spiral to a higher number (say, 2), the geometry is highly warped. If you adjust to a number without a whole number of rotations, you get failed loft conditions.

So it works for ONE shape. But it's not a solution to really replicate the shape above. It's close. But not quite.

MichaelPascoe

Try Sweep normal by @mahir. The previous approach combined with this one will let you sweep any shape with a controlled twist. If you are going to be using this technique often, I recommend making a custom feature.

https://cad.onshape.com/documents/2a44a246d2e5dc0c8017a0c3/w/b4ad96fcd9e075efb78f5248...