These days to make PCB’s you don’t need tons of expensive exposing equipment and bubble tanks, it can be done quite simply on your kitchen floor or in a garage and on a tight budget. There are many instructables already about how to create PCB's with toner and glossy photo paper or magazine pages etc. But what if you want something reliable, that peels straight off without any soaking?
Press ‘n’ Peel is a brand of toner transfer system distributed by Tekniks. I am not sure if they developed the technology but it seems to be a mylar like film with a blue powdery emulsion coated onto it . This coating is very weakly adhered to the plastic film.
The way it works is you print onto the blue side with a laser printer, then you flip it over and iron it onto the copper. The toner re-melts and sticks to the copper ( same as glossy paper ) but as the blue coating has poor adhesion to the sheet it comes unstuck as you peel it off leaving the residue only where the toner was.
It is not the only brand available though, there is also Pulsar paper and I have read somewhere there is a far eastern company that produces it but I couldn’t find any info on this.
It is a really excellent way of producing PCB’s in an instant, you can whip up a perfect batch PCB’s in 30-40 mins. It is also detailed enough to do SMD soldering and with good alignment double sided is possible. It is not without difficulty though, toner adhesion is still an issue and this is why I have written this guide to get perfect results every time.
You don’t need much at all, here are the materials I use
Designing and sizing the PCB is a whole other subject so I am going to leave it to you. As you can see I printed 2 sheets already, it is fairly straight forward. Here is a check list to help printing the image.
As for the board this board is dirty! I’ve had it hanging around for ages so its all oxidized and gerrreeasy! If you buy board and its fresh from the seller don’t bother sanding it down it will work fine. But if its like this just rub it down with some fine ‘Wet and Dry’ (say 1000) with water till it gets bright and even coloured, this removes the oxidized surface making it more consistent to use when etching.
Some boards especially ones you have cut will have burrs on the edges, it is best to sand them off as it can make the image not stick around the edges. Just lie some sanding paper flat on the desk and rub the burred edge against it until it becomes flat.
Whether new or old it is a good idea to de-grease the surface of the PCB. I use IPA (no not pale ale) as its a bit less harsh on the hands, but the acetone that we will be using later on can also be used. Just rub it down until the towel you are rubbing it down with comes up clean.