Newsgroups: sci.electronics
Path: utzoo!henry
From: henry@utzoo.uucp (Henry Spencer)
Subject: Re: plated thru holes
Message-ID: <1990May30.151434.24824@utzoo.uucp>
Organization: U of Toronto Zoology
References: <1109@uvicctr.UVic.CA.UUCP>
Date: Wed, 30 May 90 15:14:34 GMT

In article <1109@uvicctr.UVic.CA.UUCP> climber@uvicctr.UVic.CA.UUCP (climber) writes:
>... Is there a way I,
>a hobbyist with measly resources, can build a two-sided board
>with plated thru holes? ...

As far as I know, the basic answer is "no".  The plating process used to
lay down copper within the holes needs precise control of temperature and
solution chemistry if you want dependable results.  After masking off
the no-copper-here areas, the surface of the board is exposed to a
catalyst, a very thin layer of copper is laid down by a chemical
process, and then electroplating is used to build it up to a useful
thickness.  Even the electroplating is a slightly fussy job if you
want a smooth, even, solid, well-bonded layer of copper, and the less
said about the chemical process, the better.  It's not a million-dollar
investment to make it work, but you can't do it on a shoestring either.

If all you want is a demonstration technique that sometimes works and
sometimes doesn't, no problem, but if you're after trustworthy boards,
that's different.
-- 
As a user I'll take speed over|     Henry Spencer at U of Toronto Zoology
features any day. -A.Tanenbaum| uunet!attcan!utzoo!henry henry@zoo.toronto.edu