PCB

Now, the plotter was made and working, it was time to finalise the design and make a circuit board. This will be the first circuit board I make. Below, I go into a bit of detail about the making of the PCB, if you would rather watch the process in a time lapse video, scroll to the bottom of the page or click here.

Design

I realised quite early on that the PCB would need to be double sided. I downloaded and started using CadSoft's EAGLE. I make a schematic quite easily then I tried to use EAGLE's auto-routing to make the PCB, but it really wasn't happy with the the way it looked. It was time to take matters into my own hands and route the board manually.

To do this I bought a piece of A3 paper and a piece of A3 tracing paper. And just went for it:

the design

With this design, I created a digital version, the final design, with both layers, looks like this:

board in eagle

Making

Now, it was time to etch the board. I chose to use the photo-resist method as I could use the facilities of my local Hackspace, which would cut the cost. I first made an envelope for the unexposed board to fit it, with the two sides of the design on each piece of paper:

pcb envelope

Then I placed the board inside and exposed each side to 5 minutes of UV light. Then after removing the board from the paper envelope I placed the PCB into an etching tank, when it came out, it looked like this:

etched board

I then continued the process until the PCB was ready to drill. Before drilling the front and back looked like this:

pcb back

and this:

pcb front

Then I soldered all the parts onto the PCB and ended up with this:

final pcb

All of the above is summarised in the time lapse video below: