> I've seen many of PCB card made it with some type of "Magic
> Sheet" that
> not need very much aditives, so:
There are several good ways of making a PCB (Printed Circuit Board)
at home. The simplest is a non-computer method. You buy a package
of adhesive backed etch resist shapes, stick them onto a copper clad
blank circuit board, etch them in ferric chloride, and peel them off.
You can also lay out Printed Circuit Boards with software, print them
onto special paper with a laser printer, and then transfer them onto
copper clad boards.
> What does really means PCB ?
Printed Circuit Board. PCB's always use photographic and print
technologies to wire together components. Before about 1960, most
electronics was wired on big terminal strips and between the pins of
tubes. (Egad - I remember some of that stuff! I must be getting
> What's the best way to work with PCB in my Home ( in a
> student Home ) ?
You are undertaking a fairly big project. (I first did it when I was
15 years old, so it wasn't THAT big). Whatever you do, you will have
to work with caustic etchant chemicals like ferric chloride. You
will need gloves, safety glasses, a few glass trays, and an area you
don't mind making a big mess in.
A GREAT source of all you'll need, from tiny kits to bulk copper
clad, is Kepro http://www.kepro.com I buy all my PCB stuff from
them. They have a good tutorial on how to get started. You can
also contact them at spam_OUTkeproTakeThisOuTworldnet.att.net, 1-800-325-3878 or
1-314-861-0364. Ask for their catalog - it has a lot of useful
information as well.
-- Lawrence Lile
"An Engineer is simply a machine for
turning coffee into assembler code."
At 09:09 4.8.1998 +0000, Lawrence Lile wrote:
>You are undertaking a fairly big project. (I first did it when I was
>15 years old, so it wasn't THAT big). Whatever you do, you will have
>to work with caustic etchant chemicals like ferric chloride. You
>will need gloves, safety glasses, a few glass trays, and an area you
>don't mind making a big mess in.
Hmm, IMHO it is not so dramatic. Ferric chloride is not SO caustic, it is
not like acid. If you put some f.chloride on your hands, just wash them and
be prepared to yellow color on your fingers. I am regulary removing PCBs
from etching tank (or from hydroxide developper) with bare hand and I still
have all fingers after 15 years :-)
So IMHO glowes are not necessary. Glasses is a good practice, but if you
have normal dioptrical glasses, it is OK.
You can limit the mess to the minimum, suitable for normal bathroom when
you will use glass etchning tank which looks like aquarium. High and width
of the tank should be choosed according to the biggest PCB which you want
to etch. Mine is something around 40x40 cm (16x16 in) and the depth should
be around 5 cm (2in). Every shop which is making aquariums will make this
tank for you.
When you have this aquarium, you can put some tubing with holes to the
bottom (glue with silicon). You can connect this tubing to the small air
compressor. You can buy this compressor in the same shop where you ordered
the aquarium, those compressors are used for air delivery to aquariums with
Air bubbles are used for stirring the ferric chloride during etching.
If you also buy the heating element (in the same shop), you can put the
heating element into the etching tank and you have very professional setup,
comparable to most commercial etching units which costs hundreds of dollars.
The whole process is following:
1. Draw PCB on your computer, print it to clear film on laser printer
2. Put the film to the PCB board which is painted with UV sensitive
material. You can buy those PCB boards already painted in almost every
3. Expose the PCB with film to UV radiation. You can find the plans for
inexpensive UV exposure unit on web. The length of exposure is not
critical, between 3-5 minutes.
4. Develop the PCB in developper (5% NaOH), you can buy prepared solution.
5. Wash board in water.
6. Etch in above mentioned tank. The etching process will take around 20-30
7. Wash finished board with water.
8. Remove the rest of UV sensitive emulsion with acetone. I am using my
girlfriend's fingernail paint remover (I don't know the proper english words).
9. Drill PCB
Hope this will help
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* DATOR3 LAN Services spol. s r.o. *
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> Hmm, IMHO it is not so dramatic. Ferric chloride is not SO caustic, it is
> not like acid. If you put some f.chloride on your hands, just wash them and
> be prepared to yellow color on your fingers. I am regulary removing PCBs
> from etching tank (or from hydroxide developper) with bare hand and I still
> have all fingers after 15 years :-)
> So IMHO glowes are not necessary. Glasses is a good practice, but if you
> have normal dioptrical glasses, it is OK.
Please go read the EPA blurb about ferric chloride. Apparently it has some
effect on your offspring... I just read that yesterday. Of course, ferric
chloride is less bad than HNO3 and H2SO4 on the short term.
When I did my 1st hand-drawn board in school (courtesy of the chemistry
prof) I got to use 10% HNO3 that had done a bunch of boards before and it
nearly took my laquer traces off in 5 minutes.
When I did my own experiments @ home in the same period I managed to pour
some used H2SO4/CuSO4 onto the wooden floor in my room and it's still in
the parquette, after 20 years, there are 2 or 3 cyan color pieces under
the rug ;)
Also, I might add from experience that bottles and aquariums holding
unholy substances MUST be LABELED clearly. It olny takes 5 minutes of not
looking and some house aid/parent has a bottle of something that should
NOT be poured ANYWHERE in her hand. You can never be careful enough.
Parents do not expect caustic substances in bottles found in a kid's room.
Anyway, this is one of the things that one learns by doing, and please
start monitoring the ferric chloride bath temperature. It is important.
Below 20 degrees C it could take a day or so to work, while above 40
degrees you might not be able to wipe the solution off fast enough to
avoid its eating the thinner traces... ;) An aquarium heater and
thermometer is about right (both of the glass kind).
One should keep a log of boards processed, by area, and no.of sides, to
know when it's time to give up on a batch of solution. Also the ferric
chloride solution will deteriorate when exposed to the oxygen in the air,
so use a tight lid and fill the tank as much as you can. Same for bottles.
Be careful where you dispose of ferric chloride. It is a slow and
tenacious eater and unless dilluted heavily it will stay in the siphon of
a sink and eat its way through in a few days. Do not make the mistake to
use a WC to dispose of it, the flush water is not enough to dillute the
stuff. The best way is, to talk to your chemistry teacher. He will be able
to help you with this and other small details.
Ferric chloride splotched on clothes will have no immediate effect but
will eat the fabric brown/black, and then through in about 2 weeks ;) Dump
stained clothes in a vat with plenty of sodium bicarbonate dissolved in it
and leave to soak for a few hours before washing in a machine ;)
Boards processed in FeCl3 must be washed down immediately after etching,
for 10 minutes or so in running water. If this is not possible, use a tank
with bicarbonate solution.
I hope that I got all the small details right and good luck ;)