Creality K1 Max XY Rails Mod

[!] There is V2 of this mod: https://github.com/kemsky/creality-k1-max-xy-rails-mod-v2.

Description

This mod fixes K1 Max quality issues, namely excessive ringing/echo. It also increases maximum accelerations.

You must replace motor pulleys, 7.7mm belt does not fit stock pulleys, alternatively you can install non-stock motors.

This mod uses POWGE 7.7 mm belt and corresponding idler pulleys. You can use 6 mm belt with stock idlers if you add washers to compensate size differences (POWGE idlers have 10.4 mm height, washers 0.2mm (Affiliate), washers 0.3mm (Affiliate)).

I replaced stock motor pulleys with 20T pulleys for 15mm belt (rotation_distance needs to be adjusted to 40 and driver_SGTHRS must be tuned printer.cfg). You will need a bearing puller to do that (some people use printed pullers e.g. pulley puller), you have to be careful to avoid damage to motor shafts. If pulleys sit too tight you can use Dremel and make cuts to relax pulleys.

You must use camera mount from this mod, it is lower than original.

This mod changes print area depending on options you select, beware.

If you choose motor mounts option 2 - print area should remain the same.

This mod uses MGN12 rails and MGN12H carriages for X and Y axis. All rails must be cut to have 375 mm between far left and far right holes, X axis rail has max length 410 mm (375 + 17.5x2 mm), Y axis rails - 385 mm (375 + 5x2 mm).

Recommended printing materials: PA/PA-CF or similar, ABS-GF. Wall loops, top/bottom layers should be at least 5, I'd recommend 6-7, infill 40%.

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.

Published

https://www.printables.com/model/913734-creality-k1-max-xy-rails-mod

https://makerworld.com/en/models/498602

https://www.thingiverse.com/thing:6667004

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 D3vil-Design and Henlor designs.

Photos

Front view

Top view

Motor mounts

Joints

Front idlers

Toolhead

Input shaper graphs

Input shaper graphs for reinforced X axis (20x5mm aluminium sheet + 20x5mm carbon sheet).

N.B. Results for Y axis will be worse (two peaks) when X axis is not reinforced or aluminum pipe 20x10x2 is used.

X axis

Y axis

VFA

N.B. I use 0.9 degree stepper motors - 17HS6401S 0.9 (Affiliate), they are not ideal, loud, hot and have lower torque then original, but I get less VFA.

Upd. I would recommend Leadshine 42cm06 1.8 motors (low VFA, silent, high torque, need custom wiring, expensive) or LDO-42STH48-1684MAC 0.9 (requires full_steps_per_rotation: 400, loud, limited acceleration, low VFA).

42cm06 1.8 wiring

eSun Silk PLA

eSun Mate PLA

BOM

BOM contains affiliate links, this way you can support my work if you want.

! 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".

Front Idlers

Preview

Left

k1_front_idler_left.stl

Right

k1_front_idler_right.stl

Camera

k1_camera.stl

Joints

Preview

Left

k1_joint_left.stl

Right

k1_joint_right.stl

Rails mounts

You'll need at least 2 of these for each side.

Preview

Left

k1_rail_mount.stl

Right

k1_rail_mount.stl

Motor Mounts - Option 1

Use this mounts to simplify build at the cost of reducing print area. The same mounts are used for stock and non-stock motors.

Preview

Left

k1_motor_mount_left.stl

Right

k1_motor_mount_right.stl

Motor Mounts - Option 2

Use this mounts to preserve print area. Different mounts are used for stock and non-stock motors.

Motor mount left

Preview

• For stock motors - k1_motor_mount_couplers_stock_left.stl
• For non-stock motors - k1_motor_mount_couplers_left.stl

Motor mount right

Preview

• For stock motors - k1_motor_mount_couplers_stock_right.stl
• For non-stock motors - k1_motor_mount_couplers_right.stl

Tensioners

Preview

Left

k1_tensioner_left.stl

Right

k1_tensioner_right.stl

Toolhead and X axis

There are 2 options for X axis:

1. Rail only - use k1_toolhead.stl

   MGN12 rail can be used on X axis without reinforcement, but it is not rigid enough.

   Bed mesh will likely be less accurate, input shaper graph for Y axis will have at least 2 peaks, there will be vibrations on Z axis.

   There is one benefit - you probably will have print area unchanged (both motor mounts options).

2. Rail mounted on 20x10 pipe or 20x5 carbon + 20x5 aluminium sheets - use k1_toolhead_20x10.stl

   Print area will be reduced to 284 mm (Y axis) with motor mounts option 1.

Aluminium rectangular pipe on X axis

Use rail as drilling template, first make mark using 4 mm drill bit, then drill hole using 2.5 mm drill bit, then tap M3 thread.

Preview

Aluminium and carbon sheet on X axis

Alternatively, you can use 20x5 mm aluminium sheet and 20x5 carbon sheet instead of 20x10 pipe:

Preview

Toolhead

Both toolheads (k1_toolhead.stl and k1_toolhead_20x10.stl) use the same set of materials.

Preview

Other parts

7.7 mm belts increase max accelerations.

Tools (optional)

Things you might need, drill bits, taps.