Internal gear for 9g servo (360 rotation)

Before printing:

The gear has only been tested on the Tower Pro SG90, it might not fit in others.

Print using a 0.2mm nozzle

If you are using the STL files don't let the slicer place supports in the hole (it will be a nightmare to remove)

Why its usefull:

I didn't want to destroy the gears in my servo to make it turn indefinitely instead of just 180 degrees. So, I designed a gear that you can use instead, but when you want to use it as a normal servo (rotate only 180 degrees) you still can. I modeled my gear to fit the Tower Pro Sg90, so I dont know if it will fit in all servos.

Assembly:

In this video I show you how the modification can be done: https://youtube.com/shorts/LX16P5jtrcY

After printing the gear, snap the long part off (keep both pieces) as shown below:

Start dismantling the servo by removing the screws in the back.

Remove the cover over the gearbox.

Remove the gears (put them aside - don't loose them)

Note that the gearbox has 2 gears that look similar but are not the same. Identify each by watching closely the central hole because one is wider than the other.

Insert the printed plastic rod into the gear. Note that the rod only fits in the gear with the bigger hole. Ensure that the rod only pokes out of the top and is flush on the bottom.

Insert the gear with the rod in it into the servo.

Insert the other similar gear (the one without the rod)

Insert the gear that you printed into the cover

Align the cover and servo.

Put the 2 pieces together, you might need to wiggle them a bit.

Drive in the screws

Happy Printing :)