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How do you make a Helical swept datum curve?

Nose Bleed

New member
I'm trying to model a heat exchanger shaped like normal hollow spring (helical sweep), and then make vanes that wrap around this helical sweep for the heat exchager portion.

I know I'll have to use a VSS with pivot direction to perform this operation, but I'm having issues with getting the helical swept datum to model the VSS off of.

does anyone know how to do this?


New member
you have 2 options that I know of:

1. create a datum curve from equation. this works if you are good with math, & understand all that crap about coordinates. (i don't)

2. simply create a surface using the helical sweep command. your sketch is just a straight line. the endpoints of this line, which become the edges of the surface, are your trajectory for the VSS. You then put the surface on a layer, and blank the layer.

Nose Bleed

New member
okay - now my next question -

I've attempted to punch a swept circle along the helical swept surface - however when I do this, the circle is twisted. When sweeping a square through the helical swept surface, it leaves a very nicely twisted wire look, kinda like a coat hanger!

Is there a way that I can sweep a circle (for the tubing of the heat exchanger) without doing a helical sweep protrusion on top of the surface that's already there? Without getting the twisting action?

I've already done it that way (helical sweep), and it came out nice, but it seems as though it was added work to do an extra helical sweep to get the inner tubing to go through the center of the vanes.


Try a regular 'pipe' feature using the edge of your surface as the trajectory...

(not Pro/Piping.. just feature/create/pipe)

-Brian Adkins


New member
Hi Nose Bleed,

I am a new user to Solidworks, and I'd like to create a heat exchanger as well, similar to yours but in a rectangular shaped loops. Is there any tutorial on making heat exchangers, or can you teach me how to make one? thanks