Cam and Follower mechanisms

Hi everyone.

I am having a problem in Creo 2 creating a cam and follower for a simple wooden toy.

I have not done this for a while and I must have forgotten something and I think it is to do with the model parts creation as the cam assembly will not accept the surfaces of the parts to reference.

Looking on PLMS I see there is a blue line in the around the middle of the cam and a grid on the followers mating surface. I do not have these on my model. Can anyone tell me where I have gone wrong?

Is there a simple guide to creating these parts to refresh my memory as all the video tutorials I can find are for the actual assembly of the mechanism and not creating the parts.

Thanks in advance.


Re: Cam and Follower mechanisms

Hi Andrew,

You may remember the Automata tutorial I wrote based around a lobed cam? Intern, Dragos Vasilescu helped me update this for Creo 2.0 and I'll send you the draft, If you could review the document and feed back that would help with the final editing I will be doing this month. The finished document will be then be uploaded here and to

To answer your specific questions, in PTC Creo Parametric there are two ways to select the two halves of the cam connection. T

The first lets you select surfaces and to work reliably, these have to be joined at a tangent. Use the Autoselect option to let Creo find all tangential surfaces. A useful tip is to use small radii when modelling cams with steps in like snail cams.

The 'blue' line you spotted is the other way to define cams. Instead of surfaces, sketched splines can be used to define each half of the cam connection.

I hope this helps.