9x20 lathe spindle encoder geared pulleys and bracket

These parts are used to implement a spindle encoder on a 9x20 lathe using an Omron e6b2 encoder. This is useful if you are using a CNC conversion of the lathe. 

• The LatheSpindleGT2 print replaces both the spindle gear and spacer. (assumes you have removed threading leadscrew) This part will see the compression force of spindle preload. I printed in polycarbonate.

• The GT2_70 print is a geared pulley that goes on the Omron encoder shaft. You want the fit on the shaft to be a light press fit. If you need to drill it out make sure to use a mill, lathe, or drill press to keep the hole straight.

• For the bracket print you will need to drill and thread M5 bolts into the lathe. Use the belt to find a good location for the bracket. Check clearance with the spindle pulleys. Drill and tap the first hole at the main pivot, then drill a hole near the middle of the slot. You do NOT need much tension on the belt, just enough to keep the teeth engaged as the only purpose of the belt is to turn the encoder in sync with the spindle.

Note: LatheSpindleGT.stl ended up being 29mm long which caused interference with the cover. LatheSpindleGT_25mm.stl is the file I ultimately used on my lathe.

This design uses two instances of GT2 gears generated from another model. I didn't list this as a remix since this modification is for my specific use and not an improvement in the design. Highly recommend this collection.

Other Parts needed:

• Omron E6B2 encoder. I used the 100 pulse per revolution with TTL outputs. (~$25 amazon)

• 360mm GT2 Endless Timing Belt, 180 Teeth, 2mm Pitch, 6mm Width (~$2 amazon or ebay)

• Two M5 bolts approx 30mm and washers for securing the bracket to lathe.

• Quadrature Encoder inputs to your CNC. Could be parallel port inputs, Mesa board, etc...