I am having trouble making the 'Helix' function work with any consistency. My main problem is in the progression of inputs and when to just 'enter' and when to 'right click'. This is what I am doing- (pick start of axis) pick point and left click: (pick end of axis) move arrow up to point and left click, if you right click next, the whole thing disappears. If I move down the axis to the level of the start point, a perpendicular solid line will go in both directions from the start point. I move my arrow to a point on the line and left click and nothing happens. If I enter a radius into the box, nothing happens. Sometimes it will just work and others nothing. I have noticed that the times it works, the perpendicular line does not appear and once I have picked a point- the helix will construct. Anybody else having this problem? I am running under Win XP.

Hi forge,

> This is what I am doing- (pick start of axis) pick point and
> left click: (pick end of axis) move arrow up to point and left
> click, if you right click next, the whole thing disappears.

Try switching to a different view for picking that 3rd point (the one where it says "Pick start radius and anchor point".

For example if you have drawn the first 2 points to define the axis in the front view, then switch to the top view for the 3rd pick and that should work a lot better.


After the axis is defined, MoI is asking you to pick a point for where the helix will start from. The start point will be on a plane that is perpendicular to the axis line.

That makes it somewhat difficult to pick if you stay in a view where you are looking directly at the edge of that plane.

If you switch to a different view you won't be looking directly edge-on to the plane that the point is constrained to be in, and the pick will be a lot easier to do there.


Does that make sense? Let me know if you are unable to make it work even after switching to pick the 3rd point in a different view and I'll try to make an illustration to explain it better.


You should not need to right-click at any stage except for the final "Helix options" one where you can right-click if you don't need to adjust the number of turns. (it's the same as pushing the "Done" button).

I can also see now that the UI is slightly messed up - there should not actually be a "Done" button visible except for on that final stage, I will see about tuning that part up.


- Michael

Hi forge, here are some screenshots to help explain it more clearly.

Say you draw the first 2 points (defining the helix axis) in the front view like this:




So now the next pick is going to be for the start point of the helix, which will be constrained to be on this plane perpendicular to the axis (here we're looking at it from an angle in the 3D view to see it more easily):



But if you stay in that same front view, that plane that you see above is not easy to pick on, because it is being viewed directly from its edge. So in the front view that same plane would look like this:




So you need to move to a view for that 3rd pick where your mouse can kind of intersect that plane better which does not work very well if you are looking straight at its edge.

Hope that helps explain it,

- Michael

I understand the way to do it and it works now. Thanks for the tips.
Joe