Mill: Ball Screw + CNC Upgrade v. 1.0.0

Description

I have always wanted to play with a CNC mill, and I finally got around to converting my manual mill in the garage. It's been fun using the skills I've learned from building my voron 2.4 and my quad copters over the last couple of years, and challenge myself to design and build my own project. 

With what is provided in these files, I've been able to get my precision down to around .001 inches. If I continue to tweak this design, I believe I can tighten this up just a bit more, but this is fine for my current home shop. The current setup with CNCjs running on the raspberry PI isn't my favorite, and I've looking into switching over to another headless web app called gSender at some point in the future. For now, I find myself bypassing the raspberry PI altogether and running Universal Gcode Sender from laptop to execute the gcode on the controller.

I've also been using Fusion 360 to generate the milling gcode. I'm still honing my skills here, but it's has not been terrible to learn.

I've only attached the Fusion 360 design files for the conversion. Fusion 360 is free for personal use, so you can easily install the software, isolate the part you would like to make an STL for, and export it from the Fusion 360 software. I have placed an asterisk (*) in front of each of the part names to indicate the part needs to be printed. Parts with no asterisk are either hardware that need to be purchased, or original parts of the mill.

This build was done specifically for the Harbor Freight version of this mill, but there are several almost identical clones it can likely be used on:

• Harbor Freight Round column 2hp mill drill
• Ru Fong RF-31
• Grizzly G0705
• Jet JMD-18
• Enco 105-1110

BOM 

I have only provided links for items I purchased for this project. I have not provided links for items I already had on-hand):

• General

  • Filament for printed Parts (ASA): https://www.amazon.com/dp/B09DKR3BTG?psc=1&ref=ppx_yo2ov_dt_b_product_details
  • Zip ties

• Electronics

  • Aviation Connector Kit (8 pin): https://www.amazon.com/dp/B07D7TZJB6?psc=1&ref=ppx_yo2ov_dt_b_product_details
  • Aviation Connector Kit (4 pin): https://www.amazon.com/dp/B07D7SHKGK?psc=1&ref=ppx_yo2ov_dt_b_product_details
  • Mega-2560 Terminal Block Cap: https://www.amazon.com/dp/B08LH8SVBB?psc=1&ref=ppx_yo2ov_dt_b_product_details
  • Nema Enclosure (20"x16"x8") https://www.amazon.com/dp/B0924BN1P5?psc=1&ref=ppx_yo2ov_dt_b_product_details
  • AC Plug: https://www.amazon.com/dp/B07DCXKNXQ?psc=1&ref=ppx_yo2ov_dt_b_product_details
  • 110v AC -> 12v DC power supply: https://www.amazon.com/dp/B078RY6YY3?psc=1&ref=ppx_yo2ov_dt_b_product_details
  • 12v DC -> 5v DV power supply: https://www.amazon.com/dp/B0BNQ9XXCZ?psc=1&ref=ppx_yo2ov_dt_b_product_details
  • Enclose Fans: https://www.amazon.com/dp/B08BLTW8RX?psc=1&ref=ppx_yo2ov_dt_b_product_details
  • Fan Covers: https://www.amazon.com/dp/B097BH493D?psc=1&ref=ppx_yo2ov_dt_b_product_details
  • Raspberry Pi Fan: https://www.amazon.com/dp/B092YXQMX5?psc=1&ref=ppx_yo2ov_dt_b_product_details
  • AC Rocker Switch: https://www.amazon.com/dp/B07S914SFB?psc=1&ref=ppx_yo2ov_dt_b_product_details
  • Mega-2560: https://microcenter.com/product/621387/arduino-mega-2560-rev3-256kb-(8kb-after-bootloader)-flash-memory
  • Raspberry PI 4 Model B: https://microcenter.com/product/637834/raspberry-pi-4-model-b-4gb-ddr4
  • Stepper Kit w/ Drivers: https://www.amazon.com/STEPPERONLINE-Stepper-1699-34oz-4-1-8-2A-24-80VDC/dp/B0C7QH7K1T?ref_=ast_sto_dp
  • Stranded 22AWG stranded wire
  • Heat shrink
  • Soldering consumables
  • If using end stops:
    • 8 wire cable: https://www.amazon.com/dp/B09J7TCFYQ?psc=1&ref=ppx_yo2ov_dt_b_product_details
    • MR30 male and female cable ends
    • 3 Pin Micro Switches: https://www.amazon.com/URBESTAC-Momentary-Hinge-Roller-Switches/dp/B00MFRMFS6
    • Inline Aviation Connector (8pin): https://www.amazon.com/dp/B08CN5BFWD?psc=1&ref=ppx_yo2ov_dt_b_product_details
    • DB15 (VGA) Connector: https://www.amazon.com/dp/B09J7TCFYQ?psc=1&ref=ppx_yo2ov_dt_b_product_details
       
• Mechanical
  • Hex Head Screws (M6): https://www.amazon.com/dp/B0B5NW3T9B?ref=ppx_yo2ov_dt_b_product_details&th=1
  • Hex Head Screws (M8)
  • Motor Coupler: https://www.amazon.com/dp/B0991B657G?psc=1&ref=ppx_yo2ov_dt_b_product_details
    vBearing (10x22x6): https://www.amazon.com/dp/B07FVX92MJ?psc=1&ref=ppx_yo2ov_dt_b_product_details
  • Bearing (12x24x6): https://www.amazon.com/dp/B07FW3983N?psc=1&ref=ppx_yo2ov_dt_b_product_details
  • Thin Nut (12x5): https://www.amazon.com/dp/B0BJ6ZRFMR?psc=1&ref=ppx_yo2ov_dt_b_product_details
  • Thick Nut (12x10): https://www.amazon.com/dp/B09F5NRW8Y?ref=ppx_yo2ov_dt_b_product_details&th=1
  • Ball screw (DFU1605 RM1605 420mm): https://www.amazon.com/dp/B08NH59F2K?psc=1&ref=ppx_yo2ov_dt_b_product_details
  • Ball screw (DFU1605 RM1605 800mm): https://www.amazon.com/dp/B08NH59F2K?ref=ppx_yo2ov_dt_b_product_details&th=1

Tools Used

• Battery powered drill
• Hole saws
• HSS drill taps (m3)
• 3D printer (Voron 2.4)
• wire strippers
• Phillips head screw drivers
• Soldering Iron
• Heat Gun
• Multi-meter
• Fusion 360 (CAD software)

Build out

I listed these steps in the order I built the project, but I'm sure this completed differently

• Enclosure
  • drilled holes for fans, power connector, power switch, encoder wiring, and stepper wiring
  • laid out the pattern for where I wanted my electrical equipment
  • 3D printed mounts for the equipment
  • drilled and tapped holes for mounting electronics
  • installed the fans, aviation through hole connectors, power supplies, motor drivers, raspberry pi, mega-2560
  • installed grbl/mega onto the mega-2560
  • installed CNCjs on raspberry pi
  • wired everything up
  • tested motor movement
     
• Mill (I tackled each axis 1 at a time)
  • Printed all parts for the axis
  • installed the ball screw conversion (not application for the Z axis)
    • the nuts were backwards from what I wanted so I printed a generic 1605 mandrel to flip the nut
  • attached the gears/coupler
  • motor mount cap
  • installed the motor
     
• End stops
  • These are still a work in progress, but I have successful attached the z axis stops

Print Settings