AC-Bot Carriage 2.0

Please consider using Phaedrux's remix of this design -- He has fixed some minor issues and added extra part options to accommodate steppers thicker than 23mm.

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This is a 3-wheel carriage I've been working on for my C/D/J-Bot. Uses a Titan Aero heatsink and extruder combo, BL-Touch probe, KW-10 microswitch, and 50mm radial fan. You MUST use a low-profile "pancake" stepper as anything larger will not fit.

The main features of this carriage are the adjustable belt tensioners, easy-adjust third wheel tension screws, and larger improved cooling fan shroud. I've been printing with this setup for a few days so far and it has worked very well. Work in progress -- let me know if you run into issues or have questions.

Offsets:

#define X_PROBE_OFFSET_FROM_EXTRUDER -42 // X offset: -left +right [of the nozzle]
#define Y_PROBE_OFFSET_FROM_EXTRUDER 32 // Y offset: -front +behind [the nozzle]
#define Z_PROBE_OFFSET