Electronics production

The task

  • Characterize the design rules for your in-house PCB production process

How it works

In order to fabricate a working pcb, excess copper has to be removed in order to make the traces. To avoid using chemicals, the copper is mechanically removed using a drill. The final results will be much more standardised than with a chemical process.

Design

Drilling

We first had to attach the copper plte to the machine, it was done using painters tape and some super glue. This is to ensure that the plate will be firm and steady during the drilling process.

We added a weight so that the glue dried uniformly, without creating any kind of level.

In order to test the precision of the drill, we were going to be using four different drills: 0.1mm, 0.2mm, 0.4mm for making the design, and a 1mm drill for cutting it out of the board.

Using the SRM-20 interface to correctly position the machine. The drills were installed using these steps:

  1. Taking the drill to View position.

  2. Using the hexagonal tool, we attached the first drill bit to the machine.

  1. We lowered the machine (z dimension), to about 2mm from the copper plate.

  2. Carefully loosening the drill bit with the hex tool, we slowly lowered it so that it made direct contact with the copper, we then re-attached it.

Next steps were only used for the 0.1mm and 0.2mm drill bits.

As the shape of the drill is triangular, it had to be calibrated.

  1. The drill was taken 0.1mm, so that during the drilling, it only scratched the surface of the copper.

  2. We started the drilling to check if the surface was even and the board properly positioned.

    • The surface was tilted, because the drilling was not uniform across the surface.

  1. The z origin was lowered 50 um and repeated step 6.

    • Steps 6 and 7 were done three times for the first drill and four for the second.

Results

The final result:

To take the boards out, we used the 1mm tool using steps 1 through 4.

It is clear that the smaller drill were much more precise.