Practice etching

After a fair bit of research, it seems to me the easiest method for me to etch the PCB is the toner transfer method.

I found a particularly helpful forum thread on the topic at practical machinist. When I read this I was considering using a cnc controlled vertical machining centre to machine away the copper. User crossthread left this advice:

Just an FYI here but I have made about two dozen servo step and direction boards using this etching method and it could not be easier. I buy the copper clad board from Radio Shack and the ferric chloride from them as well. I use the backing paper from Avery labels to run through my laser jet printer. This prints the traces on the slick backing paper. You then take this and put it on the copper clad board and iron it on with a normal clothes iron set to "cotton". This melts the plastic toner onto the copper and you are done. If there are any small places that looks like the transfer was not complete you can fix these with a sharpie as this will resist the enchant as well as the plastic toner. Put the board in the enchant and agitate it for about 10 minutes. When all the copper is gone then you can drill your holes and solder it up.

I already had the ferric chloride and some Avery label backing paper at work, so this seemed like the easiest option. For a bit of practice I have etched a piece of aluminum and got quite good results.

This was after about 20 seconds in the ferric chloride and cleaned up with a bit of steel wool. The actual transfer of the toner took a couple of practices. At first it did not stick well and was very patchy. But on the second attempt I sanded the surface of the aluminium back with some 2000 grit wet sandpaper. I did this until it was cleaned of oils which was indicated when the water no longer formed beads on the surface. I used the heaters from plastic manufacturing machine to heat the aluminum up as I had no access to an iron. I think it was more difficult than it needed be, for the real PCB I will find an iron.

For those interested in the chemistry. Wikipedia tells us:

Another important application of iron(III) chloride is etching copper in two-step redox reaction to copper(I) chloride and then to copper(II) chloride in the production of printed circuit boards.^[15]

FeCl₃ + Cu → FeCl₂ + CuCl

FeCl₃ + CuCl → FeCl₂ + CuCl₂

I have bought the blank PCB from Jaycar, so as soon as I find a bit of time and an iron I will have a go.