Homebrew PCBs

----- Original Message ----- 
From: "Stefan Trethan" <stefan_trethan@...>
To: <Homebrew_PCBs@yahoogroups.com>
Sent: Monday, May 10, 2004 4:12 PM
Subject: Re: [Homebrew_PCBs] Re: Piezo Print Heads and Oil Based Inks


> On Mon, 10 May 2004 22:35:29 +0800, Jobet Claudio
> <jobetclaudio@...> wrote:
>
> > Hi ! I read from an old issue of radio electronics one of the ways they
> > used shellac in preparing PCB's. They first dyed the stuff so that it
> > would be visible when applied. Then, they loaded the thing into a
> > technical drawing pen and used that to directly apply the shellac as an
> > etch resist onto the blank pcb.
> >
> > Jobet
>
>
> I'm suspicious towards shellac.
> I admit i have never seen it in solved state, but it somehow is linked
> to a "sticky" image.
> Please keep in mind that in the past it was a much more popular stuff than
> it
> is today, maybe because there was no better ink around. After all we
> *have* resist
> pens now, and do not longer fill schellac into drawing pens.
>
> I tried colophony solved in alcohol in a plotter pen once. sticky mess.
> not sure if schellac is that sticky or not.

Shellac should be OK, it's quite hard when it dries. It was used for
varnishing wood a long time ago, and for 'french polishing'.

Leon