Homebrew PCBs

Hi Stuart,
I am taking my recipe from here:
http://www.pacificsun.ca/~robert/pcb/cucl.htm

The only difference is that I am using methylene orange rather than
bromophenol blue because it is cheaper and I can get it. The PH ranges for
the two indicators seem to be virtually identical so methylene orange should
be a good substitute.

You don't have to use copper oxide. You can add scrap copper to the acid and
leave it in a bubble tank for a couple of weeks. I have heard that a table
spoon of used ferric chloride speeds things up.

In the end I ordered from www.labpakchemicals.co.uk as they could supply
everything I wanted at a reasonable price. I tried phoning a local chemical
supplier and their prices were about the same but they had a 2 week lead
time. The only disadvantage with labpak is that they have a 50 pound minimum
order but I made that up with sulphuric acid for anodizing and some
flourescein for a friend to trace a drain with. Flourescein is pretty
harmless but even the slightest trace in water shows up bright green. As a
kid I added some to a swimming pool once. The whole pool ended up
flourescent green :-)

Oh, by the way I have found a great way of removing ferric chloride
deposits. I was given a tank that was in a terrible state but a few hours
soaking in concrete cleaner brought it up like new.

I know about Farnell. I have an account with RS components and they sell
quite a bit of chemistry type stuff as well.

Les



>
> You're really looking for a laboratory supplier. When I used work in a
> chemistry lab we used to buy in 2.5l winchesters (large glass bottles) or
> for HCl I remember 1l glass bottles. Nowadays it would probably be
> polythene or such I guess. I seem to remember Fisons as a supplier but the
> name "Griffin and George" comes to mind, though I think that was more for
> equipment.
>
> I suppose you know that Farnell sell things like beakers, measuring
> cylinders and other useful chemistry type stuff?
>
> What is the "mix", or process for cupric chloride etching BTW - I've only
> ever used Ferric Chloride.
>
> Stuart.
>