Rigidbot Z Wobble Solution

The Rigidbot is a bit of an older printer by now, but I'm sure there are still a few of them out there. Mine suffered from z axis wobble for a long time, many years, but decided to address it recently.

The source of the problem is the manufacturing tolerances and assembly tolerances... hard to get everything perfectly square when you have no adjustment. My X gantry guide rods and lead screw were fighting each other down at the bottom of Z travel. The alignment was off and the aluminum misalignment couplers were having to bend to account for the misalignment and it was pushing the X gantry around in weird ways leading to wobble.

You will need to print these parts before hand (I suggest something stronger than PLA), and you will need a rafter's square to check squareness.

So here is how to address this.

1. Make sure your frame is square. It might mean disassembly, but do your best to square your frame, this is going to help a lot and give you a good baseline to start and