Creality K1 XY Rails Mod

Description

This mod fixes K1 issues namely excessive ringing/echo, unstable print quality, frequent maintenance, also it makes printer quiet.

It should be compatible with regular K1 (tested), K1C and K1 SE (not tested, likely heat sink needs to be replaced with heatsink from regular K1).

• This mod does not change print area
• You must use camera mount from this mod (8mm lower than original)
• You must remove stock motor pulleys (or use non-stock stepper motors)

Belts, pulleys, motors

This mode uses POWGE 7.7 mm belt and corresponding idler pulleys. You can use 6 mm belt and stock idlers if you add washers to compensate height differences (POWGE idlers have 10.4 mm height). Also, you can use F604ZZ flanged bearings (4x12x4) and 2mm washers instead of POWGE pulleys.

You have to remove stock motor pulleys. You can use a bearing puller to do that (some people use printed pullers e.g. pulley puller). If pulleys sit too tight you can use dremel and make cuts to relax pulleys. you have to be careful to avoid damage to motor shafts

I used 20T motor pulleys for 15 mm belt (rotation_distance needs to be adjusted to 40 and driver_SGTHRS must be tuned printer.cfg).

You can install non-stock motors e.g. Leadshine 42cm06 1.8 (low VFA, need custom wiring, expensive) or LDO-42STH48-1684MAC 0.9 (requires full_steps_per_rotation: 400, loud, limited acceleration, low VFA).

This mod uses double diaphragm couplers and MF95ZZ bearings.

Belts tuning

Preferred way is to use Spectroid android app (or any other program that can show sound frequency).

Move toolhead to the middle, move X axis to have 150mm between motor mounts and XY joints.

Pluck the shortest belt on each side, displayed frequency should be the same. Target frequency is 120-130Hz, if you go higher than 130Hz you risk to damage belts.

Linear rails

This mod uses two MGN12 rails with MGN12H carriages for Y and one MGN9 rail with MGN9H carriage for X axis.

X rail has max length of 331 mm, 300 mm between far left and far right holes. X axis requires 15x15x2 mm aluminium tube (the same length as rail). It is important to use quality rails for X axis (with minimal backlash).

Y rails have max length of 314 mm (safe 310 mm), 300 mm between far left and far right holes.

Materials

Recommended printing materials are PA-GF, PA-CF, ABS-GF, ABS-CF or anything else that is rigid and can sustain high temperatures. I don't recommend printing toolhead with pure ABS. I'd recommend PA-GF or PA-CF, as screw joints tend to become loose in ABS.

Wall loops, top/bottom layers should be at least 5, for motor mounts I'd recommend 6-7.

Printing orientation

Options for maximum performance

• Use light extruder - KKm extruder (probably I'll upload my own remix)
• Use light extruder motor - LDO 36STH17-0354AHG or 36STH20-1004AHG
• Use light mgn9 rails - hollow/milled rails from FYSETC (they have 6mm height instead of 6.5mm, you have to print spacer)

License

All work in this repository falls under the Attribution-NonCommercial-ShareAlike 4.0 International (CC BY-NC-SA 4.0).

https://creativecommons.org/licenses/by-nc-sa/4.0/

Notes

Partially this work is based on creality-k1-max-xy-rails-mod and uses some CAD files made by Henlor.

Published

https://www.printables.com/model/1109686-creality-k1-xy-linear-rails-mod

https://www.thingiverse.com/thing:6893994

https://makerworld.com/en/models/931135

Photos

Photo 1

Photo 2

Photo 3

Photo 4

Photo 5

BOM, Assembly

! Flat Thin Wafer Head Screw - M3 screws with flat head that has 1 mm thickness. You can find those on AliExpress, manufacturer NINDEJIN, search for "Ultra Low Profile Head Screw".

Camera

Preview

k1_camera.stl

Front idler left

Preview

front_idler_left.stl

Front idler right

Preview

front_idler_right.stl

Joint left

Preview

k1_joint_left.stl

Joint right

Preview

k1_joint_right.stl

Y rail mounts

Preview

k1_rail_mount.stl x2

Mounting Y rails to the top frame is important if you want less vibrations. Default mount option is printed mount. You'll have to drill and tap M3 thread in the top frame.

Instead of printed mount you can buy metal plate or a set of plates to get ~8.5 mm thickness.

Y axis

See cad_rail_mgn12.FCStd for exact configuration and dimensions.

X axis

See cad_x_axis.FCStd for exact configuration and dimensions.

First, make two holes on the left and on the right, tap M3 threads, mount MGN9 rail, align it carefully and tighten screws. Use rail as drilling template, first make mark using 4 mm drill bit, then drill remaining holes using 2.5 mm drill bit, then tap M3 threads.

Tensioner left

Preview

k1_tensioner_left.stl

Tensioner right

Preview

k1_tensioner_right.stl

Motor mount left

Preview

• For stock motors - k1_motor_mount_stock_left.stl
• For non-stock motors - k1_motor_mount_left.stl

Motor mount right

Preview

• For stock motors - k1_motor_mount_stock_right.stl
• For non-stock motors - k1_motor_mount_right.stl

Toolhead clamp left

Preview

k1_toolhead_left_clamp.stl

Toolhead clamp right

Preview

k1_toolhead_right_clamp.stl

Toolhead fan spacer

Preview

Regular hotend - k1_toolhead_spacer.stl

Unicorn hotend - k1_toolhead_spacer_unicorn.stl

Toolhead

Preview

k1_toolhead.stl

Toolhead Microprobe

You can install BIQU MicroProbe sensor which is much better than original load cell probe.

[ ! ] Pins on toolhead board ("touch" connector) do not match microprobe pins, you can not use premade JST 1.25 5pins cable, you'll have to make your own.

Pins

- touch GND            -> microprobe GND    (black)
- touch 5v             -> microprobe 5v     (red)
- touch nozzle_mcu:PA8 -> microprobe servo  (yellow)
- touch GND            -> microprobe GND    (black)
- touch nozzle_mcu:PA9 -> microprobe probe  (white)

1. Remove all prtouch sections from printer.cfg

2. Edit /usr/share/klipper/klippy/extras/custom_macro.py and comment all prtouch usages

3. Remove /usr/share/klipper/klippy/extras/custom_macro.pyc and reboot

4. Add the following to printer.cfg:

   [gcode_macro _PROBE_DOWN]
   gcode:
       SET_PIN PIN=probe_enable VALUE=1
   
   [gcode_macro _PROBE_UP]
   gcode:
       SET_PIN PIN=probe_enable VALUE=0
   
   [output_pin probe_enable]
   pin: nozzle_mcu:PA8
   value: 0
   
   [probe]
   pin: ^!nozzle_mcu:PA9
   deactivate_on_each_sample: False
   x_offset: 0
   y_offset: 20
   z_offset: 0  # do PROBE_CALIBRATE
   samples: 2
   samples_tolerance: 0.05
   samples_tolerance_retries: 3
   activate_gcode:
       _PROBE_DOWN
       G4 P500
   deactivate_gcode:
       _PROBE_UP
   

5. Use PROBE_CALIBRATE macros to determine Z-Offset and save it.

6. Sometimes you can get error Communication Timeout during homing z. Use vi /usr/share/klipper/klippy/mcu.py and increase TRSYNC_TIMEOUT from 0.025 up to 0.05. Remove file /usr/share/klipper/klippy/mcu.pyc, reboot.

Depending on your hotend you may need a spacer.

Microprobe spacer

k1_toolhead_microprobe_spacer.stl

Bonus Models

Toolhead cover

Preview

k1_toolhead_cover.stl

Compact toolhead cover

Preview

k1_toolhead_cover_experimental.stl

Cable covers

Preview

Horizontal - k1_cable_cover_horizontal.stl

Vertical top - k1_cable_cover_vertical_top.stl

Vertical bottom - k1_cable_cover_vertical_bottom.stl

Z-Carriage for T8 Oldham Coupler

Preview

k1_z_carriage_oldham.stl

Side fan duct

Preview

k1_side_fan_duct.stl

Cutter block

Requires 2x25mm DIN 912 M3 screws.

Preview

k1_cutter_block.stl

Automation

export.sh/export.cmd scripts export all necessary objects to STl and STEP and optionally capture model screenshots.

# without updating screenshots:
./export.sh
# export STL, STEP and generate model screenshots:
./export.sh screenshots