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8. Computer controlled machining

Computer controlled machining Group Assignment

  • do your lab’s safety training
  • test runout, alignment, fixturing, speeds, feeds, materials,
  • and toolpaths for your machine

individual assignment

  • make (design+mill+assemble) something big (~meter-scale)
  • extra credit: don’t use fasteners or glue
  • extra credit: include curved surfaces

Shopbot procedures

How to Work with the ShopBot Machine

Introduction

This guide provides step-by-step instructions for safely operating the ShopBot CNC machine in our local lab. Follow these steps carefully to ensure accurate milling and maintain machine longevity.

Step 1: Safety Precautions

  • Wear safety goggles and hearing protection and closed shoes.
  • Secure long hair and avoid loose clothing and do not wear gloves.
  • Ensure the emergency stop button is easily accessible.
  • Verify that the work area is clean and free of obstructions.
  • Never leave the machine unattended while in operation.

Step 2: Preparing the Design File

  1. Use **VCarve **, FreeCad ** or another CAD software to create your design.
  2. Open VCarve and define material,  the bits and settings for the toolpaths
  3. Select the appropriate cutting tool (bit) for your job.
  4. Generate the G-code (ShopBot Part File .sbp). (here we work in millimeters)
  5. Transfer the file to the ShopBot computer via USB or network.

Step 3: Securing the Material

  1. Place your material on the ShopBot table.
  2. Use **screws ** to secure it.
  3. You can define where to insert the screws and avoid that the bit will go over it..
  4. Ensure the material is flat and properly aligned with the machine axes.

Step 4: Setting Up the ShopBot

  1. Turn on the control box and computer.
  2. Press Reset on the pedant.
  3. In computer: Turn off virus real time protection, unplug ethernet cable
  4. Open ShopBot Control Software.
  5. Reset the ShopBot (use the “Reset” button in the software or keyboard shortcut).
  6. Cuts -> Spindle warm up routine to warm up the spindle
  7. Move the spindle to the home position using the keypad.
  8. Set the zero (X, Y, and Z coordinates):
  9. Use the Z-probe for precise Z-height setting.
  10. Manually position the X and Y zero points as needed.
  11. Check tool clearance and confirm everything is set correctly.

Step 5: Running the Job

  1. Load your .sbp file in the ShopBot 3 software.
  2. Double-check tool settings and cutting parameters.
  3. Put on safety gear and ensure the area is clear.
  4. Turn on the spindle/router.
  5. Start the job by pressing “Start” in the software.
  6. Stay alert and monitor the machine during operation.

Step 6: Finishing Up

  1. Wait for the machine to fully stop before touching the material.
  2. Turn off the spindle/router.
  3. Move spindle away so material can be removed.
  4. Remove the material and vacuum the work area.
  5. Turn off the ShopBot control box and computer.
  6. Return tools and accessories to their proper places.

Troubleshooting Tips

  • If the machine stops unexpectedly, check the emergency stop button and reset if necessary.
  • If the bit is cutting too deep or too shallow, re-check the Z-axis zeroing.
  • If the material shifts during cutting, ensure it is properly secured before restarting.
  • For any error messages, refer to the ShopBot user manual or seek assistance.

https://chwnzyl.github.io/DFAB/fablab%20safety/Safety%20Rules%20&%20Regulations.pdf https://rules.fablabbcn.org/ https://www.cnccookbook.com/learn-cnc-basics-tutorial/

Video

From Youtube

Change bit on the Shopbot