CNC Machining

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CNC Machining at Narwhal Labs

What is CNC?

CNC is an abbreviation for "Computer Numerical Control". Using "g-code", machines use coordinate-based commands to move and perform tasks. While many tools at Narwhal Labs use CNC technology such as our laser cutter, vinyl cutters, and 3D printers, CNC will most often refer to CNC routers and milling machines. Designs are created using CAD (Computer Aided Design) software and code to run the machines is generated using CAM (Computer Aided Manufacturing) software.

Our CNC Routers and Equipment

Narwhal Labs is equipped with an AvidCNC PRO2448 and PRO6096 CNC routers, both with a 2.2kW (3HP) spindle, a NEMA34 electronics package, proximity sensors, a corner finding touch plate, mach 3 and 4 control software, and a complement of tools and tooling courtesy of AvidCNC and Bits&Bits.


CNC Router Training and Sign-Off

We have two options for CNC Router training and sign off. There is no fee for equipment training at Narwhal Labs.


Guided Option for new users:vCarve only. 1 on 1 during appointment, or classroom session dedicated only to this topic. Users should read this wiki page, install vCarve, apply NL MakerSpace ID, and import tool library prior to training. User will be walked through WCS setup in vCarve, basic design of a sign with profile/contour and engraving toolpaths. User will be guided through toolpath creation, feeds and speeds, simulation, workholding and carving. NL Staff will walk users through CNC safety, startup, spindle warmup, axis referencing and zeroing. On their own, user will model their laser cut member badge (basic rounded rectangle, thickness plugged in, WCS and reference point), add a checkmark in the right location on the badge, create an engraving toolpath, and run simulation. User will be guided through CA or super 77+tape workholding for their badge, and engrave the checkmark.
vCarve Setup Help Found Here


Self-study option for more advanced users: Fusion 360 or vCarve. User should read CNC section of Narwhal Labs wiki, install provided tool libraries and post processor(s). User must show CAM setup, WCS, and toolpath work for a small scale project of their choosing (wood or other forgiving materials recommended), demonstrate simulation. Discuss workholding options with staff. NL Staff will walk users through CNC safety, startup, spindle warmup, axis referencing and zeroing. When they run their job User must also workhold their NL badge to the bed, model the badge, and create a toolpath to carve a checkmark on the CNC section.

AvidCNC Cycle Start Checklist

  1. Locate the emergency stop
  2. Home all axis on the machine
  3. Confirm material dimensions
  4. Preview toolpaths/Run simulations
  5. Secure workholding
  6. Check router bit installation
  7. Verify work coordinate system (WCS)
  8. Review Mach 4 & G-code
  9. Test the spindle
  10. Re-install dust shoe

CNC Router Etiquette

  • CNC routers can be very loud and make unpleasant sounds. Check with others in the room before running
  • Please work with staff if you need to do long (1+hr) operations on a CNC.
  • CNC routers, even with dust collection, can throw dust and chips. Please be considerate of others that may be near by or that may be doing epoxy or finish work that is negatively affected by dust.
  • Always clean up the CNC after your work. Another person should be able to use the machine without cleaning up from a previous user.
  • Use ample workholding and tabs in your programs. Flying parts can be dangerous to you and those around you, and can damage tooling or the machine.
  • Please inform staff of any broken tools/tooling or machine faults so we can keep things running for all members. You will not be penalized for accidents.

Software

Our CNC routers operate on Mach 3 and Mach 4 control software.


We also have a license of vCarve Pro MakerSpace Edition that is located and running on our loaner laptops and the laptop for the CNC router. You can use the free trial version of vCarve Pro with our makerspace ID plugged into the help->about section of the software (contact our staff for the ID). The free trial with makerspace ID added enables all features except G-code posting and has no time restrictions.


While Narwhal Labs does not endorse any specific CAD or CAM software package, our staff has some experience with Autodesk Fusion 360 and vCarve Pro and may be able to help you with this software if needed. Fusion 360 is a full-featured CAD and CAM package that is free for personal and education use.

Software Link
vCarve Pro https://www.vectric.com/products/vcarve-pro
AutoDesk Fusion 360 https://www.autodesk.com/products/fusion-360/personal

All CAM software and packages require a "Post-Processor" to generate code that our machines will understand. The latest post-processors for vCarve and Fusion can be found below. Please download and install the latest post processor for the CAM software of your choosing.

Software Post Processor
vCarve Pro https://www.cncrouterparts.com/support/software/downloads/vectric/
AutoDesk Fusion 360 https://www.cncrouterparts.com/support/software/downloads/fusion/
SheetCAM https://www.cncrouterparts.com/support/software/downloads/sheetcam/

Feeds and Speeds

Feeds and speeds refers to the feed rate, spindle speed, and plunge depth of your CNC program for a specific bit. We maintain a list of suggested feeds and speeds for specific materials and tooling at the page linked below.
Main article: CNC Router Feeds and Speeds

Tool Libraries

Narwhal Labs maintains tool libraries for Fusion 360 and vCarve pro. These should be used as a guideline for known and safe operation. They are updated periodically with new tools and enhanced cut settings. Please ask about feed rates, spindle speeds, and cut depth if you're unsure about your cut or CAM work.

Software Package Tool Library Link
Fusion 360 Fusion Tool Library
vCarve Pro vCarve Pro Tool Library