Hi Michael,

Following on from your example on how to do a screw thread, I've seem to have found a problem?
I've included the file for you to see.

I first created a Helix of 6 twists to test, but couldn't get it to sweep? (centre at X0, Y0)
I then created another the same in reverse, but it also wouldn't sweep?

I then decided to try moving the starting point for where the Profile would start & it worked??
I also tried a couple of different amount of twists & they worked??
I then redid the 6 twist, but with the start point rotated away from the Profile & now it works??

So is this just me or is this one of those "oddball" situations or a bug???

regards Colin