simple low price glass rotary for laser engraving (K40)

thingiverse

This is a very simple Rotary for your Laser engraving machine (K40 for me). The only electronic part you probably need to buy is the NEMA 17 stepper motor. You may need to modify the angle joins for the base structure if you don't use the same aluminium rails (see FreeCAD source file). Mine are 'L' section 20x20mm from local seller. Use whatever lenght you need to match your laser bed. To secure the motor and the 3 bases (one for motor, two for the bridge pilar) on the rails I used 3mm screws and bolts. Axes for moving parts are standard 8mm threaded shaft. To keep the 8mm shaft easy to turn in the bridge part I used a 8mm theaded spacer/joiner (external diameter 11mm) and bolts and washers at each sides Two cones are needed to keep the glass in place. They are covered with a balloon envelop which is perfect to avoid the glass sliping away. 8mm bolts are used to maintain them in place. The M8 Nema 17 coupler I used is from thingiverse, joined here for convenience, sorry I cannot find who was the original author. it is here unmodified. Other models like this one may work well also https://www.thingiverse.com/thing:2815847 Have fun!