Mostly Metal Servo CNC v2

thingiverse

Introduction This is an update on my CNC build from three years ago. https://www.thingiverse.com/thing:2032881 Since the last update, I have made significant changes to the Z-axis by incorporating more off-the-shelf metal parts and upgraded the Dremel tool to a 150W brushless spindle. To secure the T8 rod in place, KP08 bearings are used as the servo motor shaft has considerable play. The brushless spindle is a worthwhile upgrade. It runs much quieter than the Dremel tool and features significantly less runout. Now, I can mill PCB with 20 mil trace. I've primarily been using this CNC to mill PCBs. With the brushless spindle, I can do it while my wife is around. Previously, the noise from the Dremel tool was so loud that I would wait for her to be out of the house before doing it. _______________________________________________________________________ Parts for the build The printed parts are shown in green in the attached drawings. All other parts listed below were purchased online: Parts Quantity LM8LUU x2 8mm rod (132mm) x2 10mm rod (300mm) x2 SBR10 linear rail (500mm) x2 SCS10LUU x2 SBR10UU x4 SK10 x4 SK8 x2 KP08 bearing x4 T8 leadscrew (100mm) x1 T8 leadscrew (300mm) x1 T8 leadscrew (400mm) x2 T8 leadscrew nut x4 Motor coupler x4 370 size geared motor with encoder x4 2040 aluminium extrusion (170mm) x4 2040 aluminium extrusion (266mm) x2 90 degree bracket (Single width) x6 90 degree bracket (Double width) x2 T8 lead screw nut holder block x1 150W brushless motor x1 NEMA 23 Mounting L Bracket x1 ER11A Collet Chuck Holder x1 https://www.amazon.com/Mergorun-Vertical-Mounted-Flexible-Coupling/dp/B071KTD1ZX https://www.alibaba.com/product-detail/57mm-dc-brushless-motor-24v-150W_60871947279.html https://www.aliexpress.com/i/32812778188.html _______________________________________________________________________ Future upgrade Right now, I believe the 10mmm linear rod for Y-axis is the weak link in this design. Changing to a linear motion guide mounted on the 2040 aluminium extrusion would significantly increase Y-axis strength. However, there's no immediate need to do so as this CNC is already capable of milling aluminium. If I mill more aluminium in the future and require a higher feedrate, I will consider this upgrade option.