Simple macro for OpenBuilds CONTROL to mill a linear cut or pocket starting at 0/0/0.
Copy the content of src/ob-linear-cut-macro.js and save it into a new macro within OpenBuilds CONTROL.
The purpose of this macro is to cut some stock by milling. It starts at 0/0/0 (x/y/z) and mills to x/y/z. In fact, depending on the placement of the stock relative to 0/0 and the x/y/z length, the macro can be used to
- cut a stock
- mill a slot into a stock
- mill a long-hole into a stock
- mill a pocket into a stock
The macro generates a sequence of G-Codes with linear milling movements in layers. The generated code will replace the one in the G-Code editor, and triggers the parsing and visualization of the code in the 3D viewer.
When the macro is started it openes up a dialog window to enter the parameters:
The milling operation is a linear movement from 0/0 to x/y (X/Y movement).
Milling is being done from vertical 0 down to the cutting depth. Dependent on 0/0/0 and the thickness of your stock this results either in a pocket or a cut.
The milling opereation will be done in vertial layers, starting at 0. The step-down defines the distance between the layers. If the step-down is larger than the hole deepth, it will be reduced to the deepth. The same is true if the remaining height of the last layer is less then the step-down height.
I needed two blocks of POM, one for a motor holder, one for holding two bearings. Each block should be 100x70x20mm (x/y/z). As stock I used a 100x500x20mm plate. To get parallel surfaces for the top and bottom, I performed the following steps:
- Using a 4mm endmill I want to trim the vertical front surface
- I used the macro to create a path to cut from 0/0/0 to 104/0/21 with a step-down of 21mm (i.e. just one path)
- I set the 0/0/0 to be close at the corner.
- I trimmed the surface and shifted the Y0 position in 0.1mm steps, until I got a clear surface.
- Next I shifted the Y0 position by 74mm (70mm + 4mm for the endmill)
- By using the macro I created a new path, as before, but with a step-down of 1mm.
- Executing the path results in cutting of my block.
The final result:
For the development I use VS Code running on linux. As the macros in OpenBuild Control are stored in an internal DB, you need to copy and paste your modified code into one macro.
There is a testsuite based on jest to test if the generated g-code fits the expectations. The setup is based on npm. If you want to run the tests, you also need to install the development dependencies with npm install.
To run the tests themself, simply start npm test.
Whenever you perform fixes, it is a good idea to start to add a test which should fail with the existing code. Next, fix the bug. Once the bug is fixed, your new / adjusted test should no longer fail.
The same is true for enhancements. First add a test, let it fail, then add the code and let the test succeed.