I was hoping you'd see it.
The only limitation to it is that the OP mentions variable widths. This could be solved with a square shaft that he can slide on different lengths of these at different points depending on how many piles he is trying to make and how wide.
I think it's can be simpler than that. Just have a long shaft with the spirals milled all along it. Then you put "stops" along the shaft where required. Bit hard for me to explain but if the stops are just either side of a "X" part of the spirals it basically turns that location into the end of the shaft and causes the cam follower to reverse at that point.
If I am understanding him right, the stops have the < and > groove to them to redirect the follower into the other track.
Quote from: Retroplayer on Feb 07, 2013, 11:57 pmIf I am understanding him right, the stops have the < and > groove to them to redirect the follower into the other track.Yes, but it's not the ends I'm asking about - it's the crossing points in the middle. When the grooves cross what's to stop the follower from changing direction? At the end of the track there's only one option and the follower has to change direction. But at the intermediate crossing points, there are two options and nothing to prevent the follower from taking either of them.
oh... the follower is long enough that it touches both sides even at the crossing points so it stays on the track it is on. And the tapers on the end of the follower are designed to allow it to flip angle at the ends. The shape of the follower is actually the most important part of the mechanism.