CNC Mill

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CNC Mill
CNC Mill.jpg

Manufacturer Marchant Dice
Obtained 2016
Location CNC Area

Hackspace 2.5

Team Tools
Induction Required No
Tools:   listall pages             {{}}

About

The CNC Mill was acquired from Wireless Things in 2016 after their close. The machine is quite unique in having a dual Y axis stepper setup; however, this does require that the start-up procedure for homeing is carefully followed.

Working area for the mill is: 345mm x 345mm x 150mm
Max feed rate is 1900mm/min.
The spindle is an Kress 1050 FME with manual speed control from 10,000 to 29,000 RPM.

The mill PC is running LinuxCNC with the Gmoccapy interface.
Gmocappy is a more friendly skin/interface to LinuxCNC than the default Axis some people might be more familiar.

More info about Gmocappy can be found here: http://www.linuxcnc.org/docs/2.7/html/gui/gmoccapy.html
Slightly older video but might be useful: https://www.youtube.com/watch?v=O5B-s3uiI6g&t=219s

Y Axis

Due to the gantry Y axis having a dual stepper drive the mill is using a development version of LinuxCNC 2.8, which can currently can cause some issue on start up.
The Y axis is also fitted with two stops, the second of which was designed and add but the hackspace to help in keeping the Y axis homing square to the X axis


Spindle

Black dial (Top Left) controls speed

The spindle's speed is manually controlled via the black dial on the top. It is a good idea to set the spindle speed whilst the spindle is stopped to minimize the operator reaching over the moving machine.

Power to the spindle is controlled via LinuxCNC during operation; It will spin up once you start running the G-Code. There is a slide switch on the side of the spindle that should be left on at all times. If it is turned off the tool will simply crash into the work piece without cutting.

Dial RPM
1 10,000
2 12.600
3 17,000
4 21,000
5 25,000
6 29,000

There is a spindle lock button to aid with tool and collet changes

Collets

We have the following collets available, currently stored underneath the monitor for the CNC Computer.

1/8" (3.17mm)
6mm
8mm
10mm

Bed

The bed is made from PT25 profile Aluminium at 375mm wide
This gives slots every 25mm for fixing.

File:20mmbedplate.pdf

We have a small selection of T-Slot nuts that will slide into these channels to provide clamping anchors. The T-Slot nuts will accept an M6 bolt.

Suitable materials

  • Most woods
  • Most plastics
  • 6082 T6 Aluminium with caution
  • Brass with caution
  • Others with extreme caution

This machine is best suited to fairly soft materials due to its aluminium frame. Soft woods, such as Pine, can be cut easily with great results. Plywood is a cheap material that can be used to produce simple profiles quickly but is likely to chip if you are doing any moulding operations. Other materials may work with extreme caution; YouTube videos are a good place to start.

If you are planning to cut hard materials materials have a couple of spare tools to hand, as you will no doubt break one. Also, do not underestimate the amount of time it will take to clean the machine after the cut. Please leave the machine as you would like to find it.

Exporting G-Code from Fusion360

Although other software is available to generate G-Code, Fusion 360 is a great free software package that has tons of CAM functionality built in.

Once you have set up your tool paths using the CAM tools in Fusion you can export the setup using the Enhanced Machine Control post processor built in to Fusion 360.

A good place to start if you're not sure with CNC programming is the NYCCNC Youtube channel.


Operation Instructions

Safety

This is a dangerous tool and should be treated as such. Your safety is your own responsibility. As a guideline, you should wear as a minimum:

  • Safety Glasses
Flying Chips, Broken Tools & loose workpieces are all possibilities
  • Ear Defenders
This machine is seriously loud, you must sit very near to it to monitor the job while it’s running and it’s not uncommon for a cutting cycle to be 30 minutes or longer. Hearing damage is a very real risk. Make sure you also warn others in the CNC room of this too.

Turn on

Turn on the monitor, PC and Control box

Control Box.jpg

The PC should auto boot into linux and automaticly log in to the nottinghack account, if not the password is hackspace
Once in you should see the following desktop, click on the Launch CNC icon to start LinuxCNC

01 Launch CNC.png

Launch

Your should now see the Gmoccapy interface to LinuxCNC
If you get an error message restart the pc and try again

02 Linux CNC Started.png

eStops

Make sure the physical eStop's have been cleared and the eStop light on the control box is out
Reset The linuxCNC soft eStop by clicking the red hand in the top right corner
Turn on the machine by clicking the power button just below
The Interface should look like this

03 Reset eStop and Turn on.png

Homing

The machine starts-up in joint mode, in this mode it is possible to move each stepper motor (0,1,2,3) independently but doing so can damage the Y axis
To use the machine we need to be in world mode where we operate X,Y,Z axis, LinuxCNC automatically switch to world mode once all the joints have been homed, but it is important to only ever use the 'Home all' option as homing a single joint at a time will damage the Y axis.
To open the Home menu click the icon in the bottom left corner of the interface. (Target and three arrows)

04 Home menu.png

In the bottom menu now click the Home all Icon (far left)
Warning This will cause the machine to move, please make sure all axis are free and clear to move and nothing is in the way for the spindle head

05 Home all joints.png

The machine should now be ready to go
Important There should be no need to home the machine again however if you need to (due to axis slip or a crash) please close LinuxCNC first and start again, as homing in world mode is not supported.

06 Ready to go.png


Loading G Code

After you have homed the machine using the instructions above, Click "Enter auto mode to run programs" on the right hand side menu. On the bottom row of icons you will see a folder icon. Click this to navigate to your ".ngc" G-Code file.

Setting G54 and tool offset

G54 Is a constant value used to provide the offset for the local coordinate system. I.e. Used to tell the CNC software where you have secured your work-piece to the table. It needs to be set before any program is run!

To set it,

  1. Enter Manual Jogging mode by pressing the appropriate button on the right hand side or pressing F3 on the keyboard.
  2. Use the control arrows to move the gantry so that the centre of the tool is sitting on the point where (X,Y,Z) is (0,0,0) on your CAD model.
  3. Make a note of the Abs readings on the DRO (Green text on the top right)
  4. Open the MDI mode of GMOCCAPY program by pressing the appropriate button on the right hand side or pressing F5.
  5. Set G54 by running the following command
  G10 L2 P1 X??? Y??? Z???
  Where ??? are the coordinates you noted down in step 3.

You should see the preview of your g-code shift to the new location.

Running a job

Once G54 is set and the code is loaded simply press the Play button located in the "Auto Mode" menu. Don't leave the job unattended and be ready with the Hoover as a lot of sawdust can be produced.

ENSURE YOU HAVE EASY ACCESS TO THE EMERGENCY STOP

Example Projects

If you have a project that uses this tool please add it to this list. It would be great to see what other people are using the CNC Mill for!