CNC Router

Our woodshop is home to a CAMaster Stinger I CNC router that is able to cut wood, plastics, and certain metals.

Certification

The CNC Basic Use & Safey class is a required certification to use this machine.

CAMaster Stinger I CNC Router

CAMaster Stinger I CNC router, computer, and compressor

CAMaster Stinger I SR-23 Specifications

Work Dimensions	Width, X	635 mm (25 in)
	Length, Y	914.4 mm (36 in)
	Height, Z	127 mm (5 in)
Spindle Power	1.7kW (2.28 HP)
Max RPM	18,000
Collet Type	ER25
Max Rapid Speed	15240 mm/min (600 in/min)
Max Cut Speed	8890 mm/min (350 in/min)
Repeatability	±0.0254 mm (±0.001 in)

Reference Material

CAMaster Site

Feeds & Speeds Calculator

VCarve Pro CAD/CAM Software

CAMaster WinCNC Machine Controller Software

FCFL References

FCFL Bit Inventory

Getting Started

The CNC is one of our more dangerous pieces of equipment. It can be a VERY energetic machine and cause flying metal if improperly configured possibly causing harm to the machine and humans nearby.

Do not use the CNC if you "think" you know how to use it. You need to know how to use it. Any other certified member should be willing to help out if any questions arise.

Safety

Standard Disclaimers:

• Don't be inebriated
• No loose items
• Standard safety gear (safety glasses)
• Tie back hair
• Don't be stupid

You should sign up for a reservation on CiviCRM before using the tool

Before Operating the CNC

CAMaster Stinger I's power switch, E-Stop, and touch probe jack (lower right)

Before doing anything, know exactly where the Emergency Stop button is. It is the large red button on the front left side of the machine.

If you press it, you can confirm it worked by reading the code on the spindle rpm controller on the bottom right of the front of the machine which should be displaying 'ER'

You must fully power cycle the CNC and reset the switch (twist) to use the CNC

Win CNC Control Software

Keyboard Controls

Z = page up/ page down, X,Y: arrow keys (labeled on keyboard)

FAQ

Stopping CNC From Software

Emergency Stop (?): Press “Esc” key. Must reload file to start again.

Pause job: Click pause (“||”) in top menu bar.

CNC Won't Start

Check that the Emergency Stop Button is not depressed. Twist to reset position

Can I do a full cut through?

Yes, though you need a sacrificial piece under your main piece. The spoilboard is technically a wear item but cut through massively decrease useful lifetime.

Coordinates

Red = Machine coordinates

Green = Local coordinates

Blue = (only for Z) top-down perspective. Zero at limit switch.

Creating The Cut Files

CAM jobs must use inches.

Using VCarve Pro

We have a Vcarve Pro Makerspace license and you can use it to prepare VCarve files (.tap) on your computer.

You can use Fusion360 to make the files, but we generally recommend testing it in the VCarve application since we have sometimes noticed strangeness with Fusion360 files. (Out of place parts etc etc)

Preparing the Cut

Pre-Check

Air compressor toggle switch (red)

Inspect the machine and bed for any debris, especially the ball screw

Check that the hose in the compressor is attached to the CNC air assist connection

Turn on the air compressor (push red toggle switch backward).

Adjust compressor to provide 60-80lbs pressure to CNC (it has its own pressure regulator).

Turn on the Vacuum

Warm Up Procedure

Spindle speed control (on front right of Stinger I)

Note: Spindle RPM DRO in thousands of RPM

1. Remove collet from spindle and set aside.

2. Warm up spindle bearing using the speed control dial on front right of CNC router. This is required for the longevity of the spindle bearings.

• Step 1: 5k RPM for 5 mins
• Step 2: 10k RPM for 5 mins
• Step 3: 18k RPM for 5 mins

Alternate Spinup: To warm up spindle, dial in half-speed (9), click Spindle and run two minutes; then dial in 18 and run two minutes, then click spindle to turn off.

Calibration

In CAMaster:

Zeroing Procedure

IMPORTANT NOTE: Must set Z zero at bottom of work if using multiple tools. You can set Z zero at top of work if just engraving with one tool.

1. Check the bed is clear of debris or obstruction

2. Click “Initialize”. This will home the Z, and X-Y axes

3. Insert tool #1.

4. Remove dust collector boot from spindle.

5. Click “Measure tool” (at corner of screen).

6. Connect touch plate and Click “Touch Top”.

7. Click “Laser On” (it’s not perfect rn, needs alignment).

8. Click “Laser X0 Y0”.

Temp notes Ignore Type G92 to clear any stored settings

Insert first tool of job in collet

Turn on laser using ‘Laser On/Off’.

Position X & Y to desired zero point, click ‘Laser X0Y0’

For ‘Z0 at top’ jobs, plug in touch plate, position under tool and Press “Touch Top” button.

For ‘Z0 at bottom’ jobs, Make sure no local Z is set. T codes in job trigger measure tool. Ensure job rapids clear all clamps.

Securing the Piece

Spoilboard has 1/4”-20 threaded sockets for clamping and otherwise securing your piece.

You can either use clamps, or preferably screw the piece down. Either directly, or using waste parts to secure it on the edges.

The Cut

Dust collector and power switch (on right side)

Spindle speeds typically 7k-18k rpm. Typical feedrate ~200ipm.

Calculate feedrate with this formula: Feedrate = (Chipload) x (Cutter Diameter) x (Number of Flutes) x (Spindle Speed)

Better to begin at lowest end of recommended feedrate and increase feed up to:

• the finish deteriorates because of vibration of the cutting tool
• tight radii causes the machine to adjust to a slower speed
• the part moves

Upcut vs Downcut vs Compression Bits: To be written...

Make sure Turn on dust collector before cutting.

Troubleshooting

Spindle wont start

Hit reset button on spindle controller console. Check that speed control knob is fully clockwise

WinCNC Wont Start

Restart PC. Pray to whatever deity(ies) you may believe in

Pinned Items from Slack #CNC and Other References

CNC Cookbook - Speeds & Feeds calculator