Newbie ques..

[Doug Ferrell]

Bill,
	I've used the method mentioned by Paul Perry where you draw the layout,
mirror it, tape it to the bare copper board, mark hole locations with a
sharp nail or center punch, and then remove the drawing and "connect the
dots" with a Sharpie permanent marker.  There are a couple of key things to
do before etching with FeCl3.  To reduce undercutting you want a fast etch.
Oxidized copper takes forever to etch, so clean the bare copper board with
very fine steel wool (just until it's shiny) immediately prior to producing
the board "art."  Etch time should then be 10-20 minutes with minimal
undercutting.
	Be sure to agitate the board (not touching the FeCl3) every 30 seconds or
so, so that the precipitant is removed from the board allowing the reaction
to continue.  I usually etch with the copper facing down so the precipitant
just falls away.  I have to lift the board to judge progress, though.  Rinse
the board after removing from the etchant and carefully remove the sharpie
marker ink with steel wool.
	Disposal of used etchant is always a pain.  The iron produced by the
reaction is a solid which settles out so you could filter or decant to
remove it.  Beyond a certain point the etchant is pretty much useless.

Good luck,
Doug

-----Original Message-----
From: owner-synth-diy at mailhost.bpa.nl
[mailto:owner-synth-diy at mailhost.bpa.nl]On Behalf Of Tom May
Sent: Monday, August 16, 1999 4:45 PM
To: Bill Crook
Cc: synth-diy at mailhost.bpa.nl
Subject: Re: Newbie ques..


"Bill Crook" <b_crook at hotmail.com> writes:

> Sorry to be a bit off topic, but this seemed a logical place for this
> question.  Whats the best way to translate circuits to pcb boards? ..and
> whats the best way to etch them? please go easy on me!

I've been etching mine with a dremel tool with a 105 or 106 bit
because I was forever getting undercutting problems with etchant and
could never figure out how to dispose of it.

Tom.