Path: utzoo!utgpu!jarvis.csri.toronto.edu!cs.utexas.edu!asuvax!anasaz!john
From: john@anasaz.UUCP (John Moore)
Newsgroups: sci.electronics
Subject: Re: PCB making ?
Message-ID: <985@anasaz.UUCP>
Date: 8 Dec 89 15:55:33 GMT
References: <2652@servax0.essex.ac.uk> <89341.162802JTW106@PSUVM.BITNET>
Reply-To: john@anasaz.UUCP (John Moore)
Organization: Anasazi Inc, Phoenix AZ
Lines: 43

In article <89341.162802JTW106@PSUVM.BITNET> JTW106@PSUVM.BITNET (Jeff Wolfe) writes:

[request for methods of making PCB's deleted]

I have experimented with the following method:
(1) Produce artwork by either drawing it on paper or by generating a
    positive from a computer program.
(2) Copy that artwork onto Meadowlake film. This is a rigid, clear film
    that will run through laser printers or copiers and is made for
    this purpose. It is available from The Meadowlake Corp,
	25 Blanchard Drive, P.O. Box 497, Northport, New York 11768
(3) Tape the film to the board with the toner side in contact with the copper
(4) Cover the film with  cotton cloth
(5) Heat an iron to about 300 degrees (max setting on my temperature controlled
    laundry iron). Heat the board/film by putting the iron on the cloth and
    gently moving it around. Press down on the iron to insure
    contact between the hot copper and the film. Be patient and take a long
    time at this to make sure all of the toner is melted.
(6) Place the hot board with the film still taped to it onto a bed of ice
    cubes. Wait for it to cool.
(7) Etch like normal
(8) Scrub off the toner.

I have had trouble with this technique, but the last time I tried it,
adding step 4 above, it worked very well. I reproduced a board that had
lines as small as 10 mils, and was relatively complex. The only problem was
one trace that etched completely away in one place. Not bad for a home
prototype process. The film is relatively expensive at about 1 dollar per
sheet, but a lot cheaper than the photo approach.

I would not recommend this approach for production - only for prototypes
or a small quantity of boards.

This has been discussed recently in Radio Electronics in the Don Lancaster
Hardware Hacker column. Don recommends using a Kroy color press for
more consistency. He also is experimenting with other, cheaper
plastic sheets. Has anyone tried overhead transparency film?

-- 
John Moore (NJ7E)           mcdphx!anasaz!john asuvax!anasaz!john
(602) 861-7607 (day or eve) long palladium, short petroleum
7525 Clearwater Pkwy, Scottsdale, AZ 85253
The 2nd amendment is about military weapons, NOT JUST hunting weapons!