cutting PCB traces

[Dave Halliday]

One very clever way I saw a few years ago was to use a large
transformer-based Soldering Gun.  These are the kind with a pistol-grip and
a transformer sitting on top.  There are two shafts that come out the front
and a copper electrode is connected between the two shafts.  When you pull
the trigger, the transformer puts a volt or two at several tens of amps
through the copper electrode causing it to heat up enough to melt the
solder.  These irons are waaaay to large ( too much heat ) to be used for
solid-state work but are more for electrical wiring, sheet-metal work,
etc...

Anyway, what this person did was to make their own electrode.  There were
actually two electrodes, not connected, spaced about 1/2 cm. apart and with
sharp points at the end.  You would put the two points on the trace that you
wanted to cut, pull the trigger and poof!  the high current would blow the
trace apart like a fuse.  The action took place over such a short time that
there was no real heat generated to cause damage to the board, it just
popped the trace open as sweetly as can be.   If you needed to repair the
cut, you would solder a piece of solid wire across the gap.

This person was doing a lot of rework on PC boards and had to cut a bunch of
traces on each one.



-----Original Message-----
From: The Proteus [mailto:proteus at ugwarehouse.org]
Sent: Monday, January 17, 2000 7:15 AM
To: synth-diy at mailhost.bpa.nl
Subject: Re: cutting PCB traces


Paul,

	It depends on how many traces you need to cut through. The way we
cut traces and re-routed them on printed circuits was usually to use a
very sharp hobby knife, mostly X-Acto's, to do the trick. I haven't
experimented with cutting mass traces with Dremel tools, namely because I
haven't hacked up my projects that bad yet. ;-) I'll ask around and get
more info for you later. 

The Proteus

The Proteus - proteus at ugwarehouse.org - Morphing technology and passion.
------<Musician>-<Producer>-<Engineer>-<UNIX Admin Extraordinaire>------
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On Sun, 16 Jan 2000, Paul Perry wrote:

> What is the best way?
> Can I use an engraving tool (eg like the Dremel
> engraver inthe TechAmerica cat) for this?
> 
> paul perry Melb australia
> 
>