Variable thickness on a revolve / loft for a toroidal knot

sanford_morton

Hi OnShape team & users, I could use your help determining how to introduce variable thickness to a revolve / loft in this document.

The inside of the toroid (donut hole if you will) should be thinner than the outside. Said another way the lattice should be more delicate on the inside and thicker towards the outside.

I'm open to any method to achieve this. My intuition would be to define the profile's width as a function of radius from the origin of the top plane - but I'm not sure how to begin setting this up.

Thanks!

Sam

konstantin_shiriazdanov

Something like this?

sanford_morton

@konstantin_shiriazdanov
Yes your radial example is exactly what I was looking for. Do you mind helping me conceptually / tactically understand how the "d(r) graph" sketch you drew is used by the variable section feature? (image below) Trying to understand how I would recreate this effect myself.

Thanks so much!

konstantin_shiriazdanov

So I defined a length parameter along path at some arbitary position #s, created a mate connector on path at position corresponding to #s to use it later as sketch plane for cross section.

Then measured a distance from those mate connector to the center axis of toroid with Measure Value feature and assigned it to variable #r. Drawed in sketch on XY plane graphical dependency law of cross section diameter #d from radius #r and created this driven variable #d in Graphic dependency feature.

Made a sketch with circular cross section using mate connector as sketch plane, cross section diameter set as #d and applied a Fix constrain to the circle center.

Finally selected the whole featurelist used for cross section definition in Variable section body feature, switched it to the Loft mode, defined a number of cross section, added a control for driving variable #s, for the range of #s values length parameter bounds are used.