Helical Sweep keeps twisting

[mah6786]

Hi,

   I'm trying to model a worm gear, I used the coil with triangle profile to generate a helix, and I'm trying to sweep my gear tooth profile along that helix, using the "perpendicular" setting.  The problem I'm having is that the perpendicular vector for the helix appears to corkscrew along the helix and also rotates the profile as it sweeps down the helix.

   How do I make the perpendicular vector always point outwards?

[mah6786]

I ended up using the "path+guide rail" option and using one of the other helices generated by the triangle coil as a guide.

[davebYYPCU]

Pics, files or a screencast will save you working out if our guess is even on the mark.

Use Sweep, Path and Guide Surface, selecting the origin plane as the surface, if you have nothing else to select.

Might help....

[HughesTooling · Accepted solution]

Here's a fairly easy way using sweep in the patch workspace to generate a helix then sweep with guide rail. The advantage using the patch sweep to create the helix is it easier to position parametrically. As @davebYYPCU  said easier to help if you supply a sample file. My example is attached.

Mark

[mah6786]

Thanks guys,

  I was making a screencast but then I stumbled upon a similar solution as yours so I just replied to my own message, but your solution is indeed better, so I'm accepting that as the solution.

Thanks!