K8200/3Drag Z Axis Trapezoid Anti Wobble - Upgrade

thingiverse

The original kit suffers from excessive wobble on the Z axis, resulting in shifting and uneven layers. This design focuses on creating a minimal yet rigid Z axis using a trapezoid lead screw. The only modifications made to the original design are those necessary for improvement. The new replacement parts are printed in ABS. To ensure proper function of the trapezoid threads, they need to be cleaned with a tap (homemade taps can also be used). A nylon print of the nut block is planned to increase wear resistance and lower friction, but the ABS version's friction turned out to be acceptable. (Note: The parts shown in photos are printed before upgrading.) If you try other materials, please share your experiences. Printer Settings: Printer: K8200/3Drag Rafts: No Supports: No Resolution: 0.3mm Layer height, 0.4mm Nozzle Infill: 50% - 100% Notes: Print Instructions: Print in ABS. A nylon print of the lead screw nut is planned to achieve better wear and lower friction, but ABS works fine. Infill and Perimeters: Lock Nuts 100% infill, 4 perimeters and 2 top/bottom layers. Other parts 50% infill, 4 perimeters and 4 top/bottom layers. Post-Printing: Parts Needed: 1x 300 - 400mm trapezoid lead screw 10mm with pitch of 2mm (TR10x2D). 1x Ball Bearing 6000ZZ or 6000RS2 (10x26x8mm). 2x M10 washer (ISO7090). 1x Motor coupler 10mm/5mm. The washers are used on both sides of the bearing and the bearing is fixed with the two printed nuts. The bearing must carry all weight of the assembly, not the coupler and motor. Other parts can be reused. Tools Needed: Trapezoid tap for 10x2mm (TR10x2D) to clean up the printed thread. Alternatively, a homemade tap from the rod part can be used as the tap is only needed to clean printed threads, not make new ones - the printed threads will guide the tap. Firmware: Change the scaling for the Z axis in the firmware from 1.25mm/rotation to 2mm/rotation to match the new pitch of the lead screw. In my case, I changed from 5120 to 3200 steps per revolution for 1/32 micro stepping (DRV8825).