Creating a board needs a lot of extra tools / skills.
I say neither I am able to produce a board myself, all these tricks were
obtained from my friend Endre Turóczi. It also involves using a
lot of chemicals. ...I'd say it's rather complicated, as long as you haven't
learnt its small techniques. Well, let's see it.
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Print the PCB to a transparent paper. I'd suggest printing on a good quality
laser printer. Take care of the contrast of the print-out.
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Take a (small, but larger than the interface) piece of coppered board.
Clean the surfaces. Use domestic cleaner materials, like scrubbers and
solvents. The aim is to clean the board from oxides and fat. After that,
wash the remaints with water and dry it. Use an electric hair dryer or
a heath blower.
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Apply photo-sensitive lac to the surface (I personally used Positiv 20
which may be known for at least Germans). For information on your particular
lac, refer to its manual. Try to achieve light and smooth surface. Keep
the board out of dust. Leave it in a warm, dark place for two or three
hours; the surface will dry.
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Cut the borders from the PCB print-out (but leave borders of an appropriate
width). Fit the picture to the prepared board (so it lies onto the board
without gaps between the surfaces) with the PRINTED SURFACE TOWARDS THE
BOARD (so the printing will be directly on the boards surface). Use small
pieces of adhesive ribbons to fix it.
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Expose the board surface to strong light. The best is to use quartz lamps;
that case, even 40-50 secs could be enough. Else, you'll have to find out
the time. In any case, avoid moving the board while exposing 'cos it could
result in a jerky positive. After exposing, remove the print-out.
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Try to develop the picture. You'll need a small amount of NaOH solution
(very watery; the appropriate concentrate depends on the photo-sensitive
material, for the Positiv 20 I used 7 thousandth, as 7 g NaOH / 1kg (1l)
water - you BTW need less than 100 cm3). (Note: the NaOH is
a very agressive chemical). The lac will come off the board where it was
exposed, and supposedly, it will remain where the print-out was black.
If not, you either over-exposed the surface or used too concentrated solution
(repeat from cleaning, etc...).
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Mix about 1-200 cm3 (should be well enough) of corroder solvent.
This will remove the copper off the plastic (or fibre-glass based) surface
where it's not lac covered. It's made of hydrogen-peroxide and hydrochloric
acid - mix 10 volume units of domestic (20%) HCl acid to one volume unit
of H2O2 (30%). These materials are agressive; take
care of not hurting yourself, anybody or anything with them. You can also
use other, not so agressive materials (like ferro-chloride (FeCl3)
solution and others); they'll also do, but the process will be slower.
After mixing, put the board into the solution and keep on watching it.
Move the board slowly up and down (avoid contacts with the liquid! - wear
protector gloves and glasses) to make the solution flow around the board.
The copper will slowly come off. When it got off from everywhere it was
supposed to, pick the board out and wash under cold water for a while.
Then dry it.
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Cut to size with saw. Smooth the edges.
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Drill the holes. You'll need a special PCB driller for the process; though,
an usual driller will also most likely do. Use Ø1 mm driller pin
for all holes
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Examine the board against connections between the traces.
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Clean the surface (use the same materials as in the beginning) from any
remaining lac.
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After this, you can either use some regular transparent lacs (Akrilan,
for example, in Hungary) or chemical solderer solutions. I used to do this
latter (TN 160, this one should be also available in Germany; suppose a
lot of others are available in different countries - it's cool, but it
dissolves with time). This will help preventing the traces from corrosion,
and also make soldering the components into the board easier.
I'd suggest taking care of the solutions after you used them. The
corroder solution remains still agressive and becomes full of metal ions.