SainSmart 3018 CNC Router Z-Axis Indicator

thingiverse

This simple pointer allows the position of the Z-axis on a SainSmart 3018 CNC router to be visualised. I've found this helpful to check the current depth of cuts during multi-pass cutting. It's also just fun to visualise the motion of the stepper motor. The pointer is deliberately very light & double ended for balance. I carefully glued it to the top of the motor spindle using a light glue (UHU in my case). I definitely WOULDN'T suggest that anything permanent be used; no CA super-glue, epoxy, etc. that may get into the motor bearing! The cap is a loose fit on top of the motor, stopping the pointer from being knock off and providing a fixed reference against which to judge the pointer angle. The lead screw pitch on the SainSmart 3018 is 4 mm, so each quarter turn of the pointer is 1 mm of Z-axis movement. Optional 'dial' also included. This part fits in the hole in the indicator cap and may be turned to any position. It has 20 markers - each correcponding to 0.2mm of Z-Axis motion. Colour one marker, say red and rotate the dial to line up with the pointer at Z=0. The current depth of cut may then be seen immediately. The design should fit any NEMA 17 (42mm) stepper motor, or the OpenSCAD design easily modified for other motor sizes. https://youtu.be/Eigg_dXcX2g?si=RTX5z5wDcjsprB8x With added adjustable dial https://youtu.be/sDuAGlJHNDk