Note: after using it a while I decided it needed a bit more resistance when shifting and just stuck another magnet on the magnets in the cups.

Flash the Arduino following the instructions provided by SimHub.

• SimHub Arduino setup - [https://github.com/SHWotever/SimHub/wiki/Arduino--Setup](https://github.com/SHWotever/SimHub/wiki/Arduino--Setup)

Assembly is fairly straight forward.

The Magnet Frame and Arm:

• Press magnets into the magnet cups aligning them so that the narrow sides attract each other. Press magnets into both sides of the arm so that they attract each other across the arm. 

• Press the bearings into each side of the arm. Insert the arm into the magnet frame and press the cross pin in place to hold it, adding a printed washer on either side (not required, but on mine there was enough clearance to use two without the arm binding on the frame - it should swing freely).

• Carefully place the magnet cups (they'll fly into place and pinch if you're not careful).

The Base:

• Solder wires a little longer than needed onto the common and normally open pins on the micro switches.

• Attach the micro switches using M2 machine screws.

• Holding the Arduino roughly in place, measure and prep switch wires to reach the pins on the diagram and the two ground pins next to them.

• Solder the wires through the top of the board and flush cut the extra wire off the bottom.

• Make sure you connect the base to the computer and test that the switches register when pressed before permanently gluing the Arduino to the base!

• Use a small dab of hot glue to hold the Arduino in the base.

• Add small dabs of hot glue to hold the wires in the provided channels, scraping any extra glue off with an old credit card so it's flush with the surface.

Carefully connect the magnet frame assembly making sure the long part of the arm sits between the two micro switches. If the USB port isn't facing the direction you want, disassemble the frame and rotate the arm 180 degrees and reassemble. Attach the base to the frame using the M3 screws.

Slide the shifter into the dovetail on the bracket, pressing firmly. The layer lines will tend to lock the sliding dovetail in place. If it doesn't seat all the way, sand the contact surfaces lightly and try again. I've given mine a very light tap with a rubber mallet to advance it one more layer line and cannot get it apart without the mallet - very solid.

Insert the post into the handle, then into the arm. I've not bothered to glue mine. I did the short-post version first in PLA, then made the long post version, printing the handle in TPU. I prefer the PLA handle but have included both here.

Attach the plate to your rig using M8 screws and t-nuts, then slide the bracket onto the plate. I've lightly sanded the plate and bracket to knock down the layer lines a little so it has less of a tendency to get locked on. It does not come loose, with any vibration tending to push the dovetail tighter.

I've included a "plate lite" version of the dovetailed bracket that I use to store my other shifter on the rig. It is attached to the 4080 extrusion using M4 screws and 3D printed t-nuts ([https://www.thingiverse.com/thing:3510542](https://www.thingiverse.com/thing:3510542)).

Parts:

• 2 - CYT1073 micro limit switches

• 2 - 608 skate board bearings

• 4 - 10x5mm round Neodynium magnets

• Arduino USB C Pro Micro clone (programs as Arduino  Leonardo). I don't recommend the older ones with micro-USB ports as micro-USB connectors are extremely fragile. [https://www.amazon.com/Teyleten-Robot-Atmega32U4-Development-Microcontroller/dp/B0B6HYLC44](https://www.amazon.com/Teyleten-Robot-Atmega32U4-Development-Microcontroller/dp/B0B6HYLC44)

• 4 - M3x10 machine screws (base)

• 2 - M2x10 machine screws (limit switches)

• 4 - M8 machine screws and t-nuts for 4080 profile.

• 4 - M4x16 machine screws and 3D printed M4 t-nuts for spare shifter mount.

This uses the mount I made for my SHH shifter, so they're easy to swap.