Mechanism connection constraints

[sbundy]

I am trying to constrain a piece that moves on a lead screw and is supported by two rods(image below). The piece should move linearly along the rods as the screw rotates. I am having an issue constraining the housing to the rods and screw as a mechanism. The best option seems to be the cylinder option, but I can only constrain it to one of the rods or screw and when I drag it, it rotates. Is there a better way to do this?

[TomU]

It's probably simplest to use a single slider connection.  Just use the axis of one of the rods and then use a plane (from the same rod) to prevent rotation.

[Kevin]

You could use two cylinder connections for the housing and shafts and a slot connection for the housing and screw. For the slot connection the thread rod would have a helical curve and the housing would have a point that moves along the helical curve.

[TomD.inPDX]

It is best to just go nuts on the different constraints to learn what each does.

There is nothing instinctual about these constraints including their implied names.

They are a very basic set with the means to lock down the parameters you require.

Hint: you can create more than 1 constraint set for a single object.

Hint2: you cannot always have direct connections as you would think in the real world.

For the lead-screw, I would do a generic gear connection between the linear traveling carriage and whatever you tie to the rotational function.