Trouble with Revolve - Tutorial

OK, first of all, I feel stupid posting a question like this on a forum, but it would appear Shapr3D doesn’t have a tech support email address anymore and is funneling everything through this user forum. So forgive me in advance…

Trying to create a helix following exactly the steps in the tutorial,

  • draw the circle
  • draw the line
  • select the revolve tool
  • select the face of the circle, click next
  • try to select the line as the edge around which the circle should revolve. But try as I might, I can’t seem to select the line… the app says its an invalid selection…

What would a “valid” selection be when I only have two things on the screen – the ircle and the line?

I think the line you are selecting is not a straight line, revolve only works with straight lines or axes. If it seems straight, there’s a chance that it has not been drawn as a straight line. It can be an arc with a huge radius or a straight spline. You can easily check this. Tap with Pencil on the line itself, if a length dimension appears it’s a line and “Revolve” should work. But please also try to draw a new line and check if it is working with it or not.

Thanks for the quick reply.
I checked the drawing and it certainly looked straight. And snap to grid was on…
Here’s a link to a screen shot.

(that oval at the top previously said “Invalid Selection” before I tried to capture the screen)

But I drew another line and it ended up being straight, I guess, because it would revolve around that line.

How can one tell for sure if a line is straight?