Laser cut Mini CNC Machine

thingiverse

Mini CNC machine constructed from laser cut 3mm ply board. Designed as a making machine with the hope of eventually machining aluminium part to build a much larger CNC machine. Designed so the parts fit on the modified bed of my K40 laser cutter (maximum 219 x 322mm). Mainly built with spares I had lying around, fixed together mostly with M3 16mm button head bolts (some other M3 sizes were used where relevant for fixing stepper motors and slide blocks etc). Y table is designed in layers to accommodate M5 t-blocks as movable clamps to hold down materials - middle layer is 2mm acrylic but could be done in 3mm or 2mm ply if you wished. Design incorporates small (approx. 10mm x 20mm) micro switches as end stops. Uses NEMA 17 stepper motors, which can be any size for the X & Y axis, but slimline (20mm depth) for the Z axis. Z axis rides on two 100mm long linear rails & blocks (type LML12B on Ebay), X & Y axis each ride on two cheap 300mm linear rails and blocks (similar in specification to type MGN 12C). Stepper motors drive T8 8mm diameter / 2mm pitch lead screws with anti backlash nuts, riding on 608ZZ bearings. Spindle is cheap 500w / 100v DC 52mm diameter motor from Ebay. Currently controlling with GRBL 1.1 on an Arduino UNO copy with a cheap CNC shield. Initial testing shows repeatable resolution on X & Y axis of less than 0.05mm.