watching the video on YouTube, thought i would share my experience with etching and the mixture i use.
i use eagle for my schematics and boards.
print to glossy photo and iron transfer. it took me a while to get the time and manner to use the iron to transfer but it usually tends to be about 1 minute per sq. in. with medium pressure on highest setting on solid surface. all irons are not created equal!!!! i use KODAK premium glossy photo paper
soak in cold water until paper starts to 'bubble' and slowly peel off, use soft bristle toothbrush to remove excess paper residue with running water and then check for errors on traces and fix with fine tip sharpie marker under magnifying lense or usb scope camera. dont want to use anything very harsh for it may take away the transfer from board.
i use a formula found online with the following: 2:1 ratio of hydrogen peroxide and hydrochloric acid (muriatic acid)
2 part peroxide in plastic or glass container and then add 1 part acid. ALWAYS ADD ACID LAST!!!!
make sure container is large enough to contain full amount of liquid.
it looks like 7-UP at first and slowly turns green as copper is etched and darker the more it etches. it will need to be re-oxidized to bring 'back to life'. can set in sun outside or somehow get oxygen back into solution.
it does also help to warm solution to +/- 80F and agitate while etching.
i find this formula a very cheap solution for the main reason of being totally reusable. i have had my solution over a year now.
my setup is in a plastic aquarium with lid from Wal-Mart.
i added a round bubble stone with air-pump held at bottom with glass beads, a check valve and a submersible heater from PETCO.
the stone keeps it well circulated and oxygenated. the 2:1 formula will lose potency after a several uses, taking longer to etch board(s) but can just add some acid to mix to regain. will not need much though.
although i may need to replace bubble stone, i find it still cheaper than the cost of ferric chloride. also ferric chloride has to be disposed of in a suitable manner when it loses the potency to etch since it is a toxic chemical.
Thought I would toss in some suggestions as I have cut lots of PCB's at home.
Heat the Ferric Chloride to 37.7C or 100F it works better when it is warm. It also works better if you have it on an orbital shaker. Come to think of it, can you make an orbital shaker? I bought a used on on E-bay but it would be need to see you make one.
Only problem I see here is that when you print with a laser on to paper it's basically on the paper and here they choose glossy to enhance this effect, where with OHP material it will inevitably melt into the plastic a bit. The Laser printer rollers get damn hot that's why you had to get the proper to stop it melting in the mechanism.
If you get it hot enough to transfer I think you still have it hot enough for the OHP to melt.
Either way if you have an OHP film you are better off with the optical method as this is much more accurate.
Ben in your PCb episode you ended up using some white paint that proved to be best can you tell us what is the exact make type of that paint. I've done this before using Black Bumper paint but the laser really made a mess of that!
