CNC Conversion Kit for Deluxe Bench Mills 6240  (Discontinued)Made in United States

CNC Conversion Kit for Deluxe Bench Mills
  • Heavy Metal CNC kit
  • Fits all bench mills with 700 mm x 160 mm table
  • 16 mm x 5 mm ball screws
  • Preloaded ball nuts for minimum backlash
  • NEMA 23 & 24 motor mounts
Part Number: 6240  (Discontinued)
Weight: 15.0 lb

Price: $775.00

This kit provides the mechanical elements you need to convert a bench mill with a 700 mm x 160 mm table to CNC. It includes ball screws, ball screw nuts, thrust bearings, and motor mounts plus the fasteners you need to install them. It does not include motors, drivers, power supply, or software. See the Documents tab for the electronics and software you will need in addition to this kit.

The ball screws are 16 mm diameter and 5 mm pitch, C7 grade with a tolerance of 30 microns over 300 mm.

All aluminum parts are clear anodized for corrosion and scratch resistance.

This kit is designed to be adjustable to any and all of the machines shown on the compatibility tab. Sometimes it just isn't possible. Because of manufacturing tolerances, there is variation from machine to machine. When installing the kit you may need to make some modifications not listed in the instructions.

Chris Chris' Tips
Made by HEAVY METAL, these kits are the most solid, rigid kit you can find. They have been on the market since 2006. They have had very few revisions in all that time.

Your mill may need some modification for everything to fit correctly.

See the Documents tab for the electronics that Heavy Metal recommends.

Here are the installation instructions.

  • 3 ball screws. 16 mm x 5 mm pitch
  • 3 Double Nut ball nuts for minimal to no backlash
  • X axis motor mount for Nema 23 motor
  • X axis ball nut block and bearing block
  • Y motor mount for Nema 23 motor
  • Y axis ball nut block
  • Z motor mount for Nema 34 motor
  • Z axis ball nut block & bearing block
  • Zero backlash helical couplings for X, Y axis for .25” Dia. Motor shafts
  • Zero backlash helical coupling for Z axis for .5” Dia. Motor Shaft.
  • New Thrust bearing for all 3 axes
  • Stainless steel cap screws for mounting motors, and other hardware as needed


This product works with the following mills. (If your machine is not on this list, we cannot verify compatibility.)

  •   SIEG X2.7L Bench Mill
  •   WEN 33075 WEN Bench Mill
  • 5550 HiTorque Bench Mill
  • 6550 HiTorque Bench Mill
  •   SIEG SX2.7L Bench Mill
This item ships directly from our supplier in Texas to you. It might be a day or two longer before it ships, and you will receive it in a separate package from other items on your order. You might receive this item a few days before or a few days after you receive items shipped from our warehouse.

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