Hitachi Z axis in the spirit of meticulous

The Ryobi router (similar to the rigid one most of you use) needs to go back on its table because my Hitachi M12VC doesn’t fit the table. The Hitachi didn’t have a simple z axis modification, so I made one and just finished it. First I took the top of the plunge apart and removed the spring from the plunge opposite from the z-axis attachment. The router is much easier to lift and lower, but will not hold it’s own weight now.


Used the following items:

  • existing Z axis mounting, motor, and wiring
  • gear kit from amazon $11. Bought the 6.35 mm version for the zaxis motor and then drilled the smaller gear to 5/16" for the 8mm shaft.
  • 8 mm threaded shaft kit $10. Cut it down to about 7" You can get a 200 mm shaft for $8.50. Drilled out bearing mounts with 1/4" bit and used 1/4-20 hardware to mount

bought the rest from the local hardware store:

  • 2x 3/4" 1/4-20 bolts (acrylic to bearing)
  • 2x 1/4-20 nuts
  • 2x 4-40 1/2" bolts (acrylic to z axis frame)
  • 2x 4-40 nuts
  • 2x 1/4" wood screws 3/4" long (bearing to sled)
  • 2x 3/8" washers
  • 2x #4 1/2" long wood screws (acrylic to acrylic)

Custom laser cut some wood and acrylic

  • laser cut some 1/4" ply for the router attach point (Took plunge bolt that holds top plastic and routed it through cut wood pieces and into the mount from underneath). Cut a 1/4" hole also in wood and inserted a 1/4" bolt from below and tightened in place with the hand screw normally used to set the plunge depth.
  • laser cut some acrylic for the z-axis spacer to tension the belt

Assembling was kind of guess and success. My sled is turning into swiss cheese with vacuum mounts I’ve tried and other ideas. the hardest part for me was getting the holes to mount the bearing down on the sled in the right location so the shaft was straight. We will see how it does with longer term use.

I have spare acrylic pieces and extra of the bolts and screws I used for one set. Let me know if anyone wants it and we can discuss the details. If you would like a kit, I can probably assemble one with everything I added for a nominal fee.
With this installed, I adjusted the z axis movement and calibrated the z-axis pitch at -24. It moves super fast. It has not yet cut. Need to figure out dust collection.

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