Fusion 360: How to correctly constrain a pin running simultaneously in a radial slot and a curved cam slot?

[thenuka_rupasinghe]

Hello Everyone,

I'm designing a cam-driven mechanism where a pin runs simultaneously in two slots:

• A radial slot in the fixed base plate.
• A curved slot in a rotating cam plate.

Previously, I managed to make it work using a combination of joints (slider for base plate, planer joint with tangential constraint for the curved slot ), but after redesigning the mechanism I'm getting joint conflicts.

What is the recommended way in Fusion 360 to constrain a pin that is captured by both slots?

Should I be using:

• Slider + Planar + Tangent?
• Pin-Slot Joint?
• Contact Sets?
• Or another joint strategy?

I'd appreciate any guidance from someone who has modelled a similar cam-slot mechanism.

Thanks!

[TrippyLighting]

Can you share the model in Fusion's native .f3d format?

[thenuka_rupasinghe]

Hello,

thank you very much for your reply.

It is an assembly file and it generates .f3z format.

Unfortunately, the file format is not supported by this forum

[TrippyLighting]

You  can zip it before uploading it.

[thenuka_rupasinghe]

Hello,

I am sending the zip file here

[TheCADWhisperer · Accepted solution]

@thenuka_rupasinghe 

Gripper.mp4

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[TrippyLighting · Accepted solution]

The tangency constraint in your design works if you delete the planar joint. It isn't necessary because the slider joint already constrains the pin's movement in the Z direction. 
In the video, I demonstrate yet another method to tie the motions of the revolute joint and the slider joint together, called a motion link:

2026-07-07 07-27-45.mp4

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[thenuka_rupasinghe]

I tried both the approaches and it worked well!

Thank You very much @TrippyLighting @TheCADWhisperer for helping me through this problem and specially in a very short time and thank you again for your time for the demonstrations.

Really appreciate your support!