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Monitor Swing Arm

With access to a computer controlled laser that can cut plywood, it was time to make something useful…well sort of.

Everyone has seen something like this, probably at the doctor’s office, an arm that bolts to the wall and holds the computer monitor. If you want to move the monitor around just grab it and do it!

Design was iterative and below is the first version, V1.0. This version had a few problems… First, the type of joint I used in the middle of the arm (the big black bolt) was too weak to work with wood, which failed during testing.  It also became obvious that I would need to offset the weight of the monitor with something since it was too hard to move up and down.

Swing Arm V1.0

Which leads to V2.0, a successful attempt! The ultimate design has 5 degrees of freedom, meaning the monitor can be moved up-down (1) left-right (2) in-out (3) be tilted forward-back (4) and rotated left-right (5). Below is a photo of the arm mounted in my lab at Stanford, which has no wall to screw into so I had to also make a clamp to grab attach it to the window sill. To offset the weight of the monitor I added a long silver spring right in the middle. The spring constantly tries to pull the monitor up, making the monitor feel really light.

Swing Arm V2.0

If you compare the joints between V1.0 and 2.0 you’ll see that 2.0 looks more like a comb, which worked significantly better (see below). Mounting to the back of the monitor was also pretty easy, just a plate with 4 screws (Metric Size 4) on a 100mm square.

Swing Arm V2.0 Back

And a close up on the clamp. The wood itself is shaped like a C and fits tightly over the metal sill. The screws on top are used to prevent the clamp from slipping off, when tightened they force a piece of wood lined with a latex tube down against the metal. Rubber on metal is huge friction (it’s how bike brakes work) so the thing doesn’t move.

Swing Arm V2.0 Clamp

A quick shot of the one I made to hold up the monitor in my apartment. Changed out the clamp for a screw mounted plate. Rock on.

Swing Arm V2.1 Apartment