Week 8

For the group assignment, we started experimenting with chemical etching to produce a PCB for the required test.

The etching method is a technique used to remove unwanted copper from a copper-clad board using a chemical solution. In simple terms, it involves protecting the parts of the circuit that we want to keep and then using an etching solution to “bite away” the unwanted copper. As a result, only the conductive traces of the circuit remain.

To produce a PCB using chemical etching, we first took a approximately 15 mm × 40 mm copper board and coated it with black paint. Then we prepared the chemical solution in which the board would be placed so that the copper surface could be chemically processed to obtain the desired design.

After preparing the solution, we engraved the painted board using a laser cutter to expose the circuit pattern. Below are the laser engraving parameters: speed: 200 mm/min, power: 30%-35%.

And downloaded the test file into this link.

Once the engraving was completed, the board was ready for the chemical etching process.

We waited about two hours, but the result was not satisfactory because all the copper areas were removed, not only the unwanted parts.

Here are pictures from the failed process.

Therefore, we repeated the process again. This time, after painting the board, we left it to dry overnight before continuing with the etching process.