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I am looking at a very cheap way of making PCB (Printed Circuit Board). I have already read about (CNC) CAD/CAM software. I am however looking at my budget for processing PCB at home at low cost. I am thinking atm (UV) Ultraviolet light may be the most cost effective way to do this. I have tried press and peel.

Dimebag wrote:I am looking at a very cheap ...

Something like this -> http://www.instructables.com/id/Home-Brew-PCBs/

Crazy - but have seen some of our students doing it with success

What about services such as Dirty PCBs. As far as I remember its offered by some member(s) of Dangerous Prototypes and really cheap. In my opinion its cheap enough in order to NOT mess around with acid at home (unless time is a relevant factor).

Interesting ideas. Now moving on from there now.

Last October, I was playing around with making my own PC board. I had read about the toner transfer method and decided to give it a try. It took me a couple of experiments to learn how to get the toner to transfer well to the board using an ordinary iron. I did not try the glossy photo paper as I had read that those kinds of paper had been changed in some way that rendered their performance poor for this purpose. Instead, the thin paper used in many magazine advertisements works pretty well, especially those printed only in black, not with colors.

A friend had given me an old Brother laser printer that he was about to pitch out. Despite reading that Brother toner did not work well for this technique, I tried it anyway.

On the first attempt, the toner did not transfer completely enough to the copper. So I used a solvent to remove it and tried again. The second time it worked pretty well for me. Here is what the copper clad board looked like with the toner transferred to it and then the paper removed using water:



After the board was etched using Radio Shack Ferric Chloride that had sat on my shelf for more than 20 years, this was the result:



I decided that was good enough and populated the board and have successfully used it.

For fast prototypes I use a laser printed image on tracing paper. I then use UV sensitised PCBs and a UV light. For liquid processing I use tanks heated with aquarium heaters with air pumped into them using rigid plastic pipes with holes drilled in them. With a bit of care you can get 0.01" resolution reliably.
I tend to use this for a quick look at a lump of circuit - from layout to testing can be under two hours - it also verifies footprints before commiting to a full blown commercial board. Total outlay was something like £150. There are limitations - I only do single sided boards, and use SMT components as much as possible. I also try to maximise track width (within reason).
Overall it's one of the best investments I made...