CNC Mill - ICP 4030

This CNC mill is a modified ICP 4030 CNC mill with a 2.2kW spindle that can spin up to 24,000 RPM. This is well suited for milling aluminium, plastics and other soft materials. It is possible to mill harder materials such as titanium too, if the depth of cut is kept very shallow.

The software running on the mill is LinuxCNC. This is a highly configurable real-time CNC control software package. Each machine will be configured differently, so what you've learnt on one machine may not necessarily apply to this one. Make sure you understand the specific details before using the mill.

• All users must complete an induction prior to using the machine.
• No wood or dusty materials. These damage the bearings, ballscrews etc.
• No ferrous materials (e.g. steel) unless you really know what you're doing. These are beyond the capability of this machine, they may work in a pinch, but are more likely to damage the mill.
• Don't try and bypass the safety interlocks. They are there to protect you and the machine.
• Compressed air cooling only (for now). Mist coolant makes quite a mess and we'd like to keep the machine clean.
• Avoid touching chips directly, as they can be sharp. Use a small brush or similar if you need to clear them out the way.
• Wear eye protection when the door is open. End mills can shatter if crashed.
• Keep fingers away from moving parts.
• Tidy up afterwards. Vacuum up your chips and wipe down any dirty surfaces.

This usage guide covers everything you need to know to use the CNC mill. This is not a substitute for doing an induction, but will serve as a reminder of the induction content.

After starting the machine and entering the password, you will be greeted with the desktop. Double-click the icon labelled my_cnc and then Execute.

Upon clicking this, you will be greeted with the start screen:

From here the machine will need to be taken out of e-stop (1) and “powered” on (2).

Once powered up, click the now active “homing” button (3).

This will take you to the following screen:

Check the CNC mill is free from obstructions and click the “home all” button (9). The machine will begin by homing the Z axis, then the X and Y axes.

Once this has completed, can click the “return” icon (10) to go back to the main screen.

Before using any tools you will need to set the tool offset. This is done by selecting a tool number. If you try and probe without selecting a tool then the probed height will be incorrect after the first tool change. Click the tool icon (4) to get to the tool menu. You will be presented with the following screen:

Once on this screen, select a tool number using the “T?” icon (12). This will bring up a dialog (13) to enter the tool number. The number you choose here is arbitrary, except for 0 which means no tool. When you click OK the machine will begin to move to the touch off position. If the selected tool number is different to your current tool then you will get the following pop-up:

When you see this pop-up, or when the tool begins to descend towards the touch probe (when the tool number hasn't changed), open the door and attach the crocodile clip to the tool. Close the door again and click OK. Once the touch off has completed the tool will begin to rise again. Unfortunately there is no prompt to remove the clip, so be sure to interrupt it manually by opening the door before the spindle starts to move back up to the original position.

Once the tool height has been set you can then return to the home screen and enter the “touchoff” screen (5):

On this screen you can set the work coordinates of each axis. The general procedure is to drive the mill until the tool just touches the part (with the wiggler you will have to do this with the door closed so the spindle can turn). Once touching you can then click the axis button (15), and set the new coordinate in the popup window (16). When your origin is at the edge of a part you will have to subtract half the tool diameter. If your origin is at the centre of the part then you can zero on one edge, move to the other edge, and set the new coordinate to be half of the current coordinate (making sure to keep the sign the same). Unlike a DRO, there is no half button, so you will have to type the coordinate manually and divide it by two (there is a built in calculator).

Once your work coordinates have been set you can now load your GCode program. Click the auto button (7) to enter this mode:

On this screen you can load a program (17), start the program (18), stop the program (19), and pause the program (20). Before starting your program check the rendered toolpath and make sure everything looks as expected. In particular check that toolpath is positioned correctly relative to your physical workpiece. Once happy you can begin the program, but keep your hand on the E-Stop in case anything goes wrong (it's quite likely). If your program includes a tool change then be prepared to open the door at the appropriate moments to add/remove the crocodile clip (if the tool number hasn't changed then the prompt won't appear asking you to change the tool).

Hopefully by the end of this you will have a functional part. Be aware of the chips stuck in the door lip as you open it, as they may fall onto you.

Be sure to tidy up and give the machine a good clean when you have finished. Please leave the CNC in a better condition than when you found it.

Before powering off the machine, be sure to shut down the raspberry pi first. Failure to do so may result in corruption of the SD card and cause a headache for future users.

If you have any further questions then feel free to leave them on the forum and we'll try our best to help.

G-Code Generation - quick point

As the machine is operated on a linux based board, a linux based G-Code is required. This can be a little finicky to generate. There are many online resources for generating an appropriate g-code which will do the job and different methods will work best for different users of the machine. I personally have found the following workflow very useable:

1. Obtain an STL - this can be done via CAD design or downloaded from an online source 2. Open STL on FreeCad software and convert into a solid model https://www.youtube.com/watch?v=GYc3BtkUtfI 3. Use the machine tab on FreeCad to generate a tool path https://www.youtube.com/watch?v=RrhahfJNn9s 3.1 A new tool may also need to be created on FreeCad to match diameter and length of your IRL endmill: https://www.youtube.com/watch?v=MHiq75sKieY&t=3s

Once the G-Code has been uploaded onto the machine, Check that the origin and orientation is matching what you expected. I find it is easier to edit the SLT orientation in stage 2 rather than editing the origin and axis of the tool path, but to each is own..

It is also good practice to do a dry run / run the machine on plastic / wax to test it is performing as it should.

For detailed maintenance information see maintenance.

A set of prompts for use when running inductions induction-prompts