sharpies will work but I've had trouble getting it thick enough. You
can get etch resist pens that look an awful lot like a sharpie but
seems to cover a little better. Resist works by a) being insoluable
and b) physically keeping the etchant from the copper. So even tar
or paint would work, too. In a pinch, I've used fingernail polish.
I've used AP and FeCl. AP seems cleaner but it doesn't seem to have
the shelf stability that FeCl does. Once I use up my AP, I'll
probably go back to FeCl. But will never buy the FeCL powder to make
it up - that's one nasty job. The premix is the way to go - you can
get it at your finer Radio Shacks (ok, mybe that's an oxymoron...).
I've never seen any place that sell a "sampler" size. Probably
because you need to have at least a pint to etch with. Built a tank
that takes a liter and it works pretty well.
I use a photo copier with ok results. Just make sure the copier
doesn't cause any distortions (photo copy a ruler in two directions
and measure the copy). It actually has one advantage over a laser
printer in that you can control the amount of toner.
--- In Homebrew_PCBs@yahoogroups.com, "pygar2" <pygar2@y...> wrote:
> I am a complete newbie at this, trying to learn enough to do it
right-
> ish the first time...
>
> I'll be doing a toner-transfer from a photocopier. Does it need to
be
> a laser copier or will a regular copier do?
>
> I don't plan on using ferric chloride. That leaves, as I understand
> it, sodium persulphate and ammonium persulphate. Are both these
going
> to work OK with the Sharpie I plan to use for touch-up? I read in
the
> archives of muriatic acid being used, which frankly is not
somewhere
> I plan to go, but if I ever do, does toner transfer work with it?
>
> The strong peroxide in wood bleaching kits-- I read of someone
using
> this in the archives, but don't know if it needs thinning, or
whether
> it even works with toner transfer.
>
> Is there anywhere I can buy just an ounce or so of each of the
> persulphates, to try them out, see which one works for me? Hate to
> buy a kilogram of something and find out it is no good for my
> purposes... and since all I have right now to do is one photoetch
> pattern I've made for some brass detailing parts I want to make, I
> don't need a huge amount of anything.
>
> TIA for any helpful advice!