Voron0 Block & Tackle Z Belt

Overview

A block & tackle Z belt implementation for the Voron 0 / Voron 0.1.

The goal was to make use of the original V0 Z motor and timing belt in a compact format, using hardware and screws already in the V0.1 BoM where possible. No additional M3 nuts need to be preloaded - so no disassembly of the frame - though two will need to be inserted into one of the Z axis extrusions.

By default this mod uses 40T & 16T pulleys, combining with the 2:1 of the block and tackle, to give a 5:1 ratio.

Larger pulleys - up to 64 teeth - can be used to increase this ratio, but will require longer timing belts.

The V0 skirt/feet are too short, so this mod requires a taller skirt, such as hartk1213's extrusion skirt mod, doubletrouble023's skirt mod, or my own Trident-style skirt mod (WiP). The V0.1 skirt/feet have enough height, though a 64T pulley may be a squeeze.

Testing has shown there is a maximum of 115mm in Z with the original design. The current files have been modified to address this, but the travel distance has not been tested.

Both the V0 and V0.1 bed positions are now supported - just print the appropriate bed_front_*.stl file.

BoM

This BoM doesn't include the 2x self-tapping screws, M3x12 BHCS, and Omron switch for the Z stop, though for clarity it does include some hardware which is reused from the V0 and V0.1 builds.

Common

Timing Belt

#Klipper Config This assumes SKR Mini E3 v2 and stock V0 Z motor.

[stepper_z]
step_pin: PB0
dir_pin: !PC5           # Remove ! if moving opposite direction
enable_pin: !PB1
rotation_distance: 32
gear_ratio: 40:16, 2:1
full_steps_per_rotation: 200
microsteps: 16
endstop_pin: PC2
position_endstop: -0.10
position_max: 120       # Check that there is enough travel - you may need to reduce this by a couple of mm
position_min: -1.5
homing_speed: 20        # Default 20, Max 100
second_homing_speed: 3.0
homing_retract_dist: 3.0

[tmc2209 stepper_z]
uart_pin: PC11
tx_pin: PC10
uart_address: 1
interpolate: True
run_current: 0.37       # For V0 spec NEMA17 LDO-35STH42-0504AH
hold_current: 0.35
sense_resistor: 0.110
stealthchop_threshold: 500

[printer]
max_z_velocity: 30      # Default 15, test before increasing
max_z_accel: 350        # Default 45, test before increasing