prototyping methods

[Grant Richter]

The GC Electronics part number for the Tin plate is 22-228-A. It comes in
two parts (liquid and powder) and costs a lot, $12.95 for enough to do six
4" x 6" boards. But it works well and keeps the boards from corroding, even
if you don't build them right away. I think it's just dilute sulfuric acid
and tin sulfate forming a super saturate solution? You just toss the boards
in for 5 minutes and they turn a nice shade of silver. Easy but expensive.
Any chemists on the list have the skinny on electroless plating?

> From: Bob Zimmer <bzimmer at voicenet.com>
> To: synth-diy at horus.sara.nl
> Subject: Re: prototyping methods
> Date: Monday, September 22, 1997 11:18 AM
> 
> At 03:11 AM 9/22/97 -0500, you wrote:
> >I use  the GC Electronics single sided pre-sensitized boards. Use a
layout
> >program that lets you make "donut" pads with a 0.010 inside diameter.
Laser
> >print a positive and get a positive "stat" copy made onto clear acetate
> >(around $8 - 12 US). I expose the board with a photoflood and develop it
> >with the GC developer. Etchant is available a Radio Shack. The local
> >surplus store sells #65 carbide drill bits for $0.50. Drill the holes
with
> >a mototool (the donut pads will self center). Then I tin plate them
(also
> >GC). A 4"x6" board costs about $5 and takes four hours or so start to
> >finish. Chemicals are somewhat expensive, $5 for enough developer to do
10
> >4 x 6 boards. The nice thing is, you can't tell the difference from a
> >commercial single sided board and you can turn a prototype in two days.
> >
> >Just my $0.02
> 
> Grant,
> 
> I'm curious about your tin plate process.  I tried a board awhile back
and
> got nothing worthwhile.  Would you mind elaborating?
> 
> 
> 
>   >=== Bob Zimmer -- Phila, PA     bzimmer at voicenet.com ===<
>   >===         http://www.voicenet.com/~bzimmer/        ===<
>   >=== "Oat-bran noise is more likely to be an issue in ===<
>   >=== situations where cereal data ia concerned [:-)]" ===<
>   >===         Analog Dialogue - Analog Devices         ===<
> 
>