Milling Machine – Circuit Boards
Overview
We are using the Modela MDX-20 and cad to mill out circuit boards.
Step 1: Setting up the machine and board
Place a sacrificial layer like an old PCB stock sheet at square(1,1) with double-sided tape (make sure it is flat, otherwise, the board will not be milled properly).
Place the PCB sheet you are milling at square(2,2) also with double-sided tape.
You will be using a 1/64 bit for milling the traces, and a 1/32 bit for cutting the board.
So start with the 1/64 bit, loosen the screws and place the bit in, tightening just enough, but not too tight 🙂
In terminal, type: move 1 1 (that moves the x and y, respectively)
On the machine, use the up and down button, to adjust the z position. Get the tool as close as you can and then manually lower it (by untightening screws, letting the bit touch the board, and then re-tightening the screws). This is how you zero the bit.
Step 2: Uploading file and changing settings in cad for milling
You can either upload a png or a cad file.
Using a png file
set z min to -.005
set z max to 1
set x min and y min depending on the location of your board.
set contour to -1.
set the tool diameter to 0.0156 (that's 1/64)
set xyz speed to 4.
Contour and save the file (don’t send to machine).
Using a cad file
some uncommenting to do(these are usually towards the bottom of the files:
make sure that dpi is set to 500: dpi = 500 # high resolution for machining
make sure that this line is uncommented: cad.function = pcb.board
and then make sure all the other settings mentionned for the png are the same.
Step 3: Sending the file for milling
Since sending the file from cad does not always end up with a complete board, we save the file and then send it through terminal.
cat myFileName.rml > /dev/ttyS0
Step 4: Uploading file and changing settings in cad for cutting
set z min to -0.065 (width of the board).
set z max to 1 set x min and y min depending on the location of your board (same as when milling)
set contour to 1
set the tool diameter to 0.0312 (that's 1/32)
set xyz speed to 0.5
We left nz at 1 and the modella was just fine cutting the board out with one pass at that speed.
Contour and save the file (don’t send to machine).
Step 5: Sending the file for cutting the board
Same as with sending to mill, go through terminal to be sure the Modela completes the traces.
cat myFileName.rml > /dev/ttyS0
PDF for download
TutorialMillingMachineCircuitBoards