This weeks assignment is to characterize the design rules for your PCB production process.
To understand the design rules for PCB production we conducted Line Test. We conducted the line test on a milling machine and a laser cutting machine to compare the precision of both the process
We downloaded a line test diagram and uploaded it into MODS for milling.
Image for group Assignment
Group Assignment Mods Interface
We set the cut-depth of the mill traces to 0.0065in which was 0.004in as default, And we gave it for Milling.
Group Assignment Milling Output
What we realised is that the minute traces till .020 was not cut with the 1/64 bit
Laser Cutting Group Assignment
We were able to do laser cutting PCB as well because our lab has a Trotec speedy 400 Flexx CO2, Fiber Laser with Power 60-250 Watts CO2 60-120 Watts Flexx and Laser Power Fiber is 20-50 watts.
We uploaded the line test diagram into the lasercutting machine software and set the parameters as shown below. For cutting the copper traces fiber laser should be used.
> Laser Cutting in progress
> Laser Output
Laser cut is more detailed and can cut even minute traces but not the same in case of Milling.
Laser Cutting was faster (7 minutes to cut) than Milling (8+2 minutes to mill).
But both took a lot of time to first set the machine.
Overall Laser is more precise, effective and takes lesser time.
Result
1) Milling
Precise traces are obtained from a line width of 0.016mm and above.
Difficult to make small trace gaps.
2) Laser cutting
Precise traces are obtained from a line width of 0.005mm and above.
Difficult to make small traces.