Cam Mate

Keeps a follower touching the outline of a cam, as the cam turns or as the follower moves.

When to Use It

Open an assembly (assemblies need the Pro plan) with at least two components in it. See Assemblies: Start and Insert Parts.
Click Mate on the Assembly tab (or right-click a component and choose Assembly tools, Mate...), then click the Mechanical tab at the top of the window.
Click the flat face of the cam plate, the face whose outline is the cam shape. It shows as Cam.
Click the follower on a different component: a corner (a point that rides on the outline), a ball (a round face shaped like a sphere), or the round face or circular edge of a roller. It shows as Follower.
Click Cam. It is lit only when the outline of that face is closed and smooth.
Click the green check. There is no value to type.
Turn the cam to see it work: drag it, or play an exploded view with a motion and pick the cam as the Component to turn in Animation Settings.

The outer edge of the picked face is the cam outline. A hole in the face, such as the bore for the shaft, is not part of it.
The outline is read as straight lines and arcs. A drawn curve (a spline) is followed as short arcs that stay within a ten thousandth of the cam's size.
Only the outline seen along the cam's axis counts. Where the follower sits along that axis is up to its other mates.

The Cam mate does not hold the follower on a track. Give the follower its own mates, for example two straight edges made Coincident plus a Parallel for a slide, or a Hinge for a lever.
Give the cam a Hinge or a Concentric so it turns on its shaft.
A roller must turn on an axis that runs the same way as the cam's axis.
A roller or a ball must be smaller than the tightest hollow (inward curve) of the outline, whether the hollow is drawn as an arc or as short straight lines. When it is too big, Cam is not offered and the window says why.
Flip Mate Alignment is not available for this mate.
The mate is saved with the assembly and comes back when you open it. Undo takes it away in one step.

The follower rides on the outside of the outline. A groove, or a track on the inside of a ring, is not supported yet.
A flat faced follower is not supported yet. Use a corner or a roller.
The outline may have at most 1,000 pieces.
A sharp corner, where two pieces of the outline meet at more than 20 degrees, is refused.
After Replace Components the Cam mate shows a missing entity. Right-click it, choose Edit Feature and pick the cam face again.
The AI tools cannot make a Cam mate yet.

"The cam outline has a sharp corner. A cam needs a smooth closed outline: lines and arcs that meet without a corner." Round the corners of the cam, or pick another face.
"The roller is too big for the hollow parts of the cam outline. Pick a smaller roller or a corner." A hollow (inward) curve of the outline, drawn as an arc or as short straight lines, is tighter than the roller or ball. Use a smaller roller or ball, or a corner.
"The roller must turn on an axis that runs the same way as the cam's axis." Pick the roller's round face, not its flat end, and check that it is parallel to the cam's shaft.
"That face has no closed outline to follow. Pick the flat face of the cam plate." The picked face is not the flat side of the cam.
"The cam outline has more than 1,000 pieces." or "That outline has too many points to read." The outline is too detailed. Use a simpler cam shape.
The follower stops. Its own track does not let it move as far as the outline needs. Check the follower's other mates.
Every button is grey. The picks do not fit any mate on this tab. The status line says what is missing, for example "Pick more entities." Remove a pick (click it again or press Delete in Mate Selections) and try again.
"Collapse the exploded view to add mates." Mates cannot be added while the assembly is exploded.
The Over defined prompt appears. The new mate conflicts with the ones already there. See Mates: Fixing Mate Problems.

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