Homebrew PCBs

Where a friend of mine works at a French university the old camera they've 
used for 20 years for making PCB artwork from 2 1 masters has just died on 
them, so he asked me for details of my photoetch process using a cheap HP 
inkjet printer to produce the transparencies. I've just made a test PCB for 
him with 8/8, 10/10 and 12/12 mil tracks, four of each in two groups. They 
all came out OK, and the lettering on the board which used a 5 mil line 
width was also reproduced perfectly. He'll check the track widths with a 
measuring microscope, but they look fine under 14x magnification apart from 
the edges being a bit rough with no sign of overetching.

They are thinking of spending a lot of money upgrading their PCB facility 
with PTH and a laser plotter, but knowing how slowly things move over there 
it'll take at least a year, and my method might get them out of a hole.

Leon
--
Leon Heller
Amateur radio call-sign  G1HSM
Yaesu FT-817ND transceiver
Suzuki SV1000S motorcycle
leon355@...
http://www.geocities.com/leon_heller

Will you tell us all about your process? I looked through your posts
for the last year (almost) and your photo album, but apart from a
couple of photos of finished boards and a UV unit, couldn't find anything.


--- In Homebrew_PCBs@yahoogroups.com, "Leon" <leon355@...> wrote:

Where a friend of mine works at a French university the old camera
they've used for 20 years for making PCB artwork from 2 1 masters has
just died on them, so he asked me for details of my photoetch process
using a cheap HP inkjet printer to produce the transparencies. I've
just made a test PCB for him with 8/8, 10/10 and 12/12 mil tracks,
four of each in two groups. They all came out OK, and the lettering on
the board which used a 5 mil line width was also reproduced perfectly.

Leon Heller

----- Original Message ----- 

From: "phildimond" <my-yahoo-groups@...>
To: <Homebrew_PCBs@yahoogroups.com>
Sent: Saturday, April 12, 2008 9:01 AM
Subject: [Homebrew_PCBs] Re: Test of my photoetch process


> Will you tell us all about your process? I looked through your posts
> for the last year (almost) and your photo album, but apart from a
> couple of photos of finished boards and a UV unit, couldn't find anything.

It's quite standard:

Artwork on Mega Electronics Jetstar Premium film with an HP Deskjet 5940
UV exposure on positive resist pre-coated PCB
Development in sodium hydroxide solution
Etching in hot ferric chloride with continuous manual agitation in a small 
plastic dish in a larger container with very hot water in it.

Leon
--
Leon Heller
Amateur radio call-sign G1HSM
Yaesu FT-817ND and FT-857D transceivers
Suzuki SV1000S motorcycle
leon355@...
http://www.geocities.com/leon_heller