Ender 3 dual Z axis carriage , adjustable for antibacklash nut

thingiverse

Questions? Announcements. Support. https://www.facebook.com/groups/679001895990790 The Ender 3 is a fantastic machine, but it has its limitations. One of the main issues is that the X-axis gantry is supported only by one Z screw. Adding a second screw was a logical step to improve stability and precision. To take my printer to the next level, I wanted more precise movement from the whole Z assembly. That's why I decided to rebuild the way Z nut and screw are adjusted. This project requires patience and precision, so please keep in mind that it's not for beginners. My goal is to upgrade my Ender 3 with a dual Z axis system, using antibacklash nuts, dual Z motor, better motor mounts, bearing support for the Z axis, synchronizing belt for added precision, and fully adjustable axes for straight-line movement of the Z nut/screw. Right now, I'm at step one: designing and building another bracket to allow precise adjustment of the Z nut so that the Z screw is perfectly vertical. To help with this, I used a motor mount from OneEyedDesign (https://www.thingiverse.com/thing:2932344). I also added a bracket for the stock nut. Next up is step two: rebuilding the left side assembly without an extruder mount for direct drive setup (https://www.thingiverse.com/thing:4188950). Here's where I am so far: * Step 1: New bracket for second Z axis designed to allow precise adjustment of the Z nut, using motor mounts from OneEyedDesign. * Step 2: Rebuilding left side assembly without extruder mount for direct drive setup. * Step 3: Top adjustable bearing blocks for Z screws - completed (https://www.thingiverse.com/thing:4214242). * Step 4: Cable management adaptors - pending. Hardware and Assembly For the X-axis bracket, you'll need: - Leadscrew 8mm diameter, 2mm pitch, 8mm lead (stock screw) 370 mm length - Nut - designed for common spring-loaded antibacklash nut, but easily changeable - M5 x 40mm (or longer) - 3 pieces - Two spacers 8mm outer diameter, length 8mm, hole 5mm - Two or six M5 nuts - One small and one bigger spacer with 5mm hole - Two screws M4x12mm - Two M4 nuts Notes * Leadscrew: You can use a different lead, but you'll need to change both screws and nuts. My next step is changing the screw to 2mm lead for more precise movement. * Nut: The stock nut is terrible - very short with lots of wobbling and fast wearing. I recommend using antibacklash nuts or designing your own adjustable anti-backlash nut without a spring. * Motor: Use the same stepper motor as the main Z axis - 34mm length, 1.8deg stepper motor. I recommend using a board with dedicated drivers for dual Z like SKR1.3 or newer and disable stealthchop for precise movement.