FlatCAM pratical tutorial: silkscreen geometry – Part 4
Another important features is the possibility to mill inside object, so you can create element or write letter over PBC.
I load again the schema of my test PCB.
As you can see in the image I add some letters and my logo, the better way to write they is to use paint features.
First of all you must generate a geometry over Gerber to create a delimiter countour for generate internal geometry.
You can set the parameters
Tool dia and
Pass overlap to 0, the result is this
ok, seems nothing change, but if you pay more attention the green of silkscreen gerber is more dark now, because you have create a geometry over a gerber and It’s difficult to see, you can add a little margin to manage a letter less thin.
Now we have a container to generate a paint, so select the geometry created.
Paint tool have a lot of parameter, you must learn the better for every need. It’s very similar to Non-Copper cleaning, but with some selectable option.
As Non-Copper cleaning you can select multi tools and various method, but for out scope we don’t use nothing of that, we want only write some letter and a little logo, other options are more suitable for biggest silkscreen.
As you can see I insert a very little diameter, because our scope is to write some letter that are too little for our tool, but It’s sufficient that are readable. This little value can be not sufficient for the smollest letters because if letters is too thin nothig is painted, for example, now I’m going to apply the parameter you read upper to all geometry of silkBottom file, so I select All Polygons and click Create Paint Geometry.
Now you can see that some letter is perfectly managed
and here some letter more thin have problem with this Tool Dia too big
So the solution is simple, you must generate a paint geometry fitted for every set of letter, you must reduce the Tool Dia to fit perfect every letter.
You can use 2 selection type
- Polygon selection: every time you click on Create Paint Geometry you are going to select a letter or othe geometry (of reference object selected on the upper of panel);
- Area selection: you can select a set of elements (letters or other) using the selection tool, when you click on the button the selection starts from the corner and the next click closes the selection and when you click with the right mouse button the action is performed for the whole area you have created.
You can use paint to write or create little logo with your cnc
I normally select a standard method to fill element with geometry, I think this solution is pretty good, but we can select other system, here the 3 different method:
For me the best, simply and powerfull
Basically it starts from the outer perimeter and follows the shape until it covers the entire surface.
As you can understand from the name you are going to plant a seed and It grows circularly.
Not so good in a lot of circumstances, you risk to have a lot of lift for no reason.
Straight line method
Simply It start to mill a series of horizontal lines from top to the bottom.
- FlatCAM pratical tutorial: introduction, installation and import
- FlatCAM pratical tutorial: copper traces geometry
- FlatCAM pratical tutorial: clean non copper area
- FlatCAM pratical tutorial: silkscreen geometry
- FlatCAM pratical tutorial: contour
- FlatCAM pratical tutorial: gcode and PCB milling
You can find Gerber, fritzing, images and FlatCAM project files here.