SK-Go Belted-Z
Assembly Manual

1 set of belt clamp:

• 1 aluminum belt clamp plate

• 1 self-printed belt clamp base

• 4 bolt M3x10

• 2 bolts M3x16

• 6 nuts M3

Make 2 sets.

Download the STL for belt clamp base from SecKit GitHub repository.

Action

Assemble and attach belt clamps onto L-shape bed supports. Don't fasten those M3x10 bolts for later belt installation.

• 1 planetary gearbox

• 1 self-print stepper mount

• 1 20T pulley

• 4 bolts M3x10

• 2 bolts M4x8

• 2 T-nut M4

Download the STL for stepper mount from SecKit GitHub repository.

Action

Attach the planetary gearbox as shown in the picture. Don't fasten the M4x8 bolts for later belt tensioning.

Adjust and fasten the position of 20T pulley so the closed loop belt won't be scratched by pulleys.

Pull the gearbox to Y-Max direction and fasten bolts to tense the belt. Note that both sides of the belt should be equal tensed.

Define SK_BELTED_Z as true and compile, flash a new firmware for your SK-Go². Below are the major

Z_CURRENT: 600mA is more than enough
Z steps/mm: 3200
DEFAULT_MAX_FEEDRATE: at most 7.5 mm/s
HOMING_FEEDRATE_Z: at most 450 mm/min (7.5 mm/s x 60 s/min = 450 mm/min)

Download SecKit Marlin source code from SecKit GitHub repository.

Exam

To provide enough torque and static friction against free fall of the bed frame, a high reduction ratio 1:20 gearbox is used so the max feed rate is low. Make sure the max feed rate is at most 7.5 mm/s, or the stepper will start skipping steps with strange noise.

Open the cap from its front end. Loosen the bolts with WD40 if needed.

Fill plenty of grease until the chamber is almost full. Don't worry, the gearbox is simple inside. If the gears fall out just put them back as shown in the picture.

Exam

Don't over-torque and strip the threads of those 4 tiny bolts.