8. Computer controlled machining
Group assignment
- Test runout, alignment, speeds, feeds, and toolpaths for your machine.
Since our lab do not have CNC machine yet, so we ask for New Life Psychiatric Rehabilitation Association brrow their lab for using their CNC machine from China. Here is the User’s Guide. Please read first before you operated.
In that lab, they provide Oriented Strand Board (OSB) finishing as a material. There are two different thickness of OSB: 12mm and 18mm.
As same as a CNC machine in our Lab, milling on aluminum platform will increase it's depreciation. Changing aluminum platform is much more expensive and complicated. Therefore, putting a second OSB (as a waste plate) on top of the aluminum platform help to keep aluminum platform condition. Also, OSB is cheaper and easier to get than aluminum platform.
First OBS: As a waste plate putting on top of aluminum platform
Second OBS: For milling you work
Mounting screws in 4 corners because stabilizing second OBS will not be moved during the operation.
Before milling, use Detector (from Original Manufacturer) for detecting Z axis origin. Since the height of detector is 20mm, so for setting the End Mill between your materials (for me: is OSB) is 20mm, same with the height of detector. For resetting X and Y axis origin, just click the button for rest. BE CAREFUL!!! the position of XY origin of Software Interface and CNC Machine is different.
If you change other materials or the thickness materials, you need to use detector to reset Z axis origin again.
Runout test before milling because it help you to make sure that you file still in your CNC work area. The video show the process.
Feed rate: 1206
Spindle speed: 12000
Thanks for German designing the testing file for testing CNC performance.
Tool paths results: (12mm thick of OSB)
| Expected | Actual |
|---|---|
| 15.00mm | 14.99mm |
| 15.90mm | 15.91mm |
As you can see, the expectation and actual performance lost about 0.01mm. We all agree the existing setting is the perfect setting for milling our works.
Joinery Fit Test with T Bone:
As you can see the vieo, 16mm is too losose. 15mm is tight enough for making joint.
File Download
Fusion 360_OSB Jointing Testing_F3D