[sdiy] PCB Etching

[Scott Bernardi]

Sorry Jim, I meant to send this to the list.

> I used to use a Pyrex 9"x12" disk that I would rock back and forth to make
> "waves" over the PCB. Others have already mentioned clean copper is
> essential. Also be careful to keep your fingerprints off it while applying
> the transfers and tape and/or drawing on it.
> If you can afford it, an etchant tank is well worth it.
> http://www.web-tronics.com/ has very nice ones with aerator and heater for
> $40.  I use Ammonium Persulfate for etchant rather than ferric chloride for
> etchant.  I also tin the boards with Tinit solution.  All this stuff is
> available at Web-tronics (also called Circuit Specialists), including photo
> sensitized boards and developer.
>
> patchell wrote:
>
> >     This sounds about par for a first time etch...sounds a lot like my
> > first experience.  To get the 20 minute etch time, you really have to
> > agitate the solution.  Being poor at the time (35 years ago), I made a
> > cradle that I rocked back and forth.  It was tedious, but it worked.
> >
> >     It does take a bit of practice...however, you might also be learning
> > why a lot of us just say no to PC board etching.
> >
> > Prototek wrote:
> >
> > >       I gave my first shot at PCB etching using a cheap Radio Shack
> > > kit. It
> > > consisted of 2 copper clad boards, etching solution, a marker, and
> > > resist
> > > ink remover.
> > >    Instead of using the marker I opted for the transfer stickers. I
> > > was able
> > > to transfer them on to the board after a little practice. I then
> > > placed the
> > > board in the etching solution for 20 minutes(like instructions said).
> > > I
> > > checked it out and there wasn't even a quarter copper faded yet!
> > >    To make a long story short, I let it sit about another 45 minutes
> > > and
> > > jiggled the tank around a little. The copper was finally gone, but my
> > > traces
> > > were horrible!! Leaving the PCB in the solution that long made my
> > > transfer
> > > stickers thinner and brittle, thus allowing the solution to creep
> > > through.
> > >
> > >    Is this how etching with solution always is? What method does
> > > everyone
> > > else use.
> > >
> > >                        -proto
> >
> > --
> >  -Jim
> > ------------------------------------------------
> > * Visit:http://www.silcom.com/~patchell/
> > *-----------------------------------------------
> > *I'm sure glad Merry Christmas comes just once a year
> > * -Yogi Yorgensen
> > ------------------------------------------------
>
> --
> Scott Bernardi
> sbernardi at home.net

--
Scott Bernardi
sbernardi at home.net