Motorized Spray Can Cap

For an art project I needed a lightweight way to trigger spray cans with a motor.

I am using a very lightweight (9g) SG-90 servo motor made for remote-controlled hobby planes. The trigger requires a lever to put enough force on the cap of the spray can. The length of the lever arm is bit of trade-off. When running the servo on 5V (6V is recommended for max torque on a SG-90) torque is sufficient to reliably trigger the release of paint but there is a bit of a delay till the servo has pressed the cap beyond the “paint-release” point. If that works for you depends on your application.

Total weight of fully assembly including motor and screws: 28.7g

The plastic is slightly flexible and wraps around the metal bulge on top of the can. The whole assembly can simply be slid on and off without a lot of wiggling.


Parts:

Part Quantity
Servo motor SG-90 1
Screw M2 8mm DIN912 4
Screw M2 12mm DIN912 1
Screw M2 6mm DIN912 2
Nut M2 DIN934 1
Screw M3 35mm DIN912 1
Nut M3 DIN934 1

Files:

Fusion360 screenshot

CAD files are linked below:

For commenting, remixes, etc. see Printables


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