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If you overexpose the board, the light will penetrate the black
area and give bad results.
Don't touch the board during the exposing.
After 3-4 minutes I turn off the UV-lamp and remove the board
to let it cool down.
It needs to cool down because it is quit hot (30-40 degree
Celcius) and if you put a hot board into the developing liquid
(water solution of NaOH) the reaction will got to fast and
you loose the lines.
So, let the board cool down (shake it) and then put into the
When you buy the NaOH powder, you can read the label how
much mixing water you need.
If you think the developing reaction goes to slow (not at
all) try to warm the solution just a little.
Also here you need to experiment a bit.
When I mix the NaOH I get about 2 litre. Then I use some "dummy"
boards to test the solution.
When you test the "dummy" boards make sure you expose
it to UV light as it would be a real board.
During the developing phase you will see the pattern from
the films grow on the board.
For me the developing phase takes about 1-2 minute then I
shower the board with fresh water to remove NaOH remains.
Etch the board
There are several different solution used for etching. I advice
you to buy a etch kit with powder.
The etching process will be fastest when the solution is warm.
I put the board into a plastic jar filled with etch solution.
I then put the jar into a pan with water. I warm the pan on
the stove until the water almost boils.
The heat will transfer into the jar and the etching process
will work great.
I move (shake) the jar to speed up the etching time.
The etching time is about 5-10 minutes.
Here you can see the finished circuit boards with edges and
lines sharp as razorblade.
All you need to do now is to clean the board with Acetone
to remove the protective plastic film.
A good board will improve the quality of your projects,
Specially if you are into RF homebrewing.
Now you know how to make PCB of your own.
You need to buy some stuff, but I assure you the result will
Click here to see photo and read how to solder SOIC and smd
Many people has written to me and asked about the UV lamp.
I advice you to go to a electronic shop and ask for UV light
(tube) and they will help you.
This is what Rafael Santos from Portugal did and I want to
show his great UV-box.
Rafael say "They told me that the lamp TL 05 is great
to do PCB's ,
this lamp is used in stores to kill fly's, they go against
the lamp and bzzz....."
Watch and enjoy...*smiling*
I think his work will inspire all of you to build your own
You can always mail me if there is anything unclear.
I wish you good luck with your projects and thanks for visit
my page.How to make your own PCB
Printed Circuit Boards -- how to make nice looking ones of
your own designs
There are a handful of ways available to the hobbyist to
turn your own designs into PCBs. They yield results of different
qualities, where the quality seems to be inversely proportional
to the amount of mess you make (in most cases), and amount
of money you spend (in all cases). I'll talk a bit about each,
and then compare them all at the bottom of the page.
Any process that involves making your own board will have
a number of steps in common. At a high level, here's what
Procure a bare board (coated with a thin layer of copper
on either one or both sides). Most methods will use a plain
board; photolithography requires one coated with special light-sensitive
If you have a plain board, scrape off any burrs along the
board edge (you want a flat copper surface; I use a fine file
for this), and clean it well to remove oxidation and finger
oils. I start with fine steel wool, follow up with denatured
alcohol to remove any oils or grease, and finish by buffing
with a very clean towel. From this point on, you'll want to
handle your board only by the edges to avoid getting finger
oils on it.
Design your circuit. Depending on how you plan on actually
producing the board (read on...), your design will take one
of a number of different forms -- a hand-drawn set of lines
on paper, a computer-drawn diagram, a design file you'll send
off to a manufacturing house...
If you'll be producing the board yourself, transfer your design
of desired copper traces to the plated side(s) of your board;
the transferred traces are resistant to your etching liquid
(more on this later). Most home-brew board production methods
differ only in how they accomplish this step. If you are generating
a design via computer, you'll have to put some thought into
which way your printed design faces (i.e., printed "right
way up" vs. mirrored). There are enough ways to approach
this that I split this information out onto its own page here.
Etch the board you've traced -- here, an etchant chemical
removes all non-masked copper; after it's done, give the board
a good wash under running water to remove all traces of the
etchant. In most cases, the etchant will either be Ferric
Chloride or Ammonium Persulfate (Ferric Chloride is more popular).
These are available in both liquid (i.e., premixed) and powder
form; the powder is generally quite a bit cheaper, but requires
care when mixing.
Also note that etching proceeds faster with (1) warmer etchant,
and (2) agitation. Along with saving you time, fast etching
also produces better edge quality and consistent line widths,
so fast is good in this step. I pre-heat Ferric Chloride etchant
in the microwave for 40 seconds or so (you want it hot enough
to be barely-comfortable to the touch), and slosh it around
by hand as it's doing its work. An old plastic freezer container
(with lid) is good for this (it allows for vigorous agitation,
without making you wear any of the etchant). You can keep
the etchant warm by putting the etching tray inside a larger
tray or sink filled with boiling water.
Note that you don't want to get Ferric Chloride solution
too hot, since it will start generating Hydrochloric acid
fumes if you Design and Fabricate Custom Printed Circuit Boards
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5. Finishing up
This document describes my personal opinion on how to manufacture
the double sided PCBs. Other ways of doing this exist, and
this only describes the way I find most efficient in low volume
PCB manufacture. This page does NOT tell you how to design
a PCB. Throughout this page it is asumed that you are building
a Quad Camera Frame Grabber, but of course the same methods
and procedures apply to other PCB's as well (of course you
need the PCB design and drill files applicable to that project
instead of the ones linked to here).
The PCB design is eurocard size based (160mm by 100mm), and
two complete QCFG PCB's are fitted on this surface. If you
want to make only one, you will have to edit the PCB designs
provided accordingly, and use a 80 mm by 100 mm PCB instead.
The quality of the finished PCB strongly depends on the quality
of the UV-photographic resin coated PCB and its AGE. Until
recently I used to coat my own PCBs with liquid UV-sensitive
resin, or use non-branded generic presensitized PCB's, and
I usually ended up with a pile of defective PCBs. To offset
this I have grown accustomed to manufacturing a small batch
(this saves time setting up equipment, but is less efficient
in materials), ending up with one good PCB for every two copper-clad
epoxy-fiberboard coasters. After (just recently) having found
a GOOD brand of pre-sensitised material, having virtually
100% yield (none out of the 20 eurocard PCBs I've made the
last half year were defective) I strongly recommend using
"BUNGARD-original" PCBs. I am NOT associated in
any way with this manufacturer, NOR involved in trade of these
PCBs. I do not get paid in any way for these recommendations,
it is my own sincery opinion that they are good. These (european
manufacturer) boards can in Europe be ordered through CONRAD
electronics in germany (www.conrad.de); I don't know about
the rest of the world.
Please note that making these PCBs involves some potentialy
hazardous chemicals and tools. It is your own resposibility
to take suitable precautionary actions! If you do not know
what these suitable precautionary actions are, DO NOT use
these chemicals and tools. I recommend wearing protective
goggles, clothing, and chemical resistant gloves all the time
when handling these chemicals, tools and PCBs!. In some countries
the use of some of the tools and chemicals may be bound to
restrictions, such as proper waste disposal and licenses,
or may even be forbidden. It is your own resposibility to
act according to your countries/states laws and regulations.
A complete list of protective equipment and procedures nescessary
or recommended is NOT included in this discription; it provides
just some basic hints and reminders.
I want to make some points especially clear: both NaOH (caustic
soda) and Iron Cloride are very unhealthy. Caustic soda dissolves
your clothing, skin, and tissue (amongst others), and Iron
Cloride permanently stains it yellow (amongst others). Do
not use use NaOH in conjuction with metal (especially aluminium)
containers or equipment. Do not use Iron Chloride in conjunction
with metal, as this may dissolve/react or become stained.
Iron Chloride etches stainless steel! Some plastics may dissolve
in or react with Iron Chloride (e.g. POM) or Caustic soda
(e.g. some floor coverings/LINOLEUM)
Find out what you need to do in case of an accident BEFORE
THE ACCIDENT ACTUALLY HAPPENS. Find out what measures to take
when your skin or eyes come in to contact with these chemicals,
and find out what to do when they are ingested. Like any dangerous
goods they should be kept out of reach of children, preferably
in a locked cabinet. Use safety caps. Mark bottles containing
chemicals with their names, their "strength" (kg/L
or Mol/L), their date of preparation, and with a notice stating
that they are dangerous to skin & eyes and should never
be ingested. Use strong chemical resistant PLASTIC containers,
as glass may (more easily) break in case of chemical reactions,
overheating or wrong handling. Make sure your labels and ink
resist the chemicals as well!. Do not store the chemicals
in a place where it may potentially become warm, such as a
car or in direct sunlight.
Please note that the UV-light used to expose the UV-sesitive
resin coated PCB's is not exactly healthy either. Wear suitable
UV-protective glasses, UV-protective gloves, long sleeves,
and keep skin and eye exposure times as short as possible,
or even better prevent it altogether by using a light tight
"UV-PCB-exposure-box". The exact type of light/lamp
used determines how dangerous the UV light is; if the manufaturer
does not explicitly state that the lamp is safe, don't assume
it is. I've seen people use UV lamps designed to sterilize
equipment, and I've seen peoples skin turn crispy after just
a few minutes exposure. Exposure of the eyes to UV light may
lead to cataract.
The dust released during cutting and drilling PCBs is detrimental
to your health as well, and may (amongst others) lead to skin
irritation, sore eyes and various lung diseases. Avoid contact
as much as possible. Never inhale the dust; wear a good quality
dust protective mouth cover. I prefer to use a damp piece
of cloth to wipe my work-area clean regulary. After use, before
it dries up again, I dispose of this piece of cloth in a proper
2. Materials and tools list:
To make this PCB you need:
1 good quality double sided UV-sensitive photoresist coated
PCB, eurocard size, 1.5mm thick epoxy fibre base material,
35um copper cladding.
NaOH pellets (these are used in Holland as chemical kitchen-drain-deblockers),
1 tablespoon for 1 L developer
warm and cold running water.
Iron chloride pellets, about 1kg dissolved in 1 L water is
enough for 1.7 L etchant, which is enough for (depends on
design) about 40 PCB's.
A4 size overhead projector transparancy(s), inkjet compatible
1 Inkjet printer, EPSON STYLUS COLOUR is fine, others I do
not know. SOME deskjet printers may require software modifications
or special software in order to produce usable transparancies;
these changes are beyond the scope of this document.
2 pieces of (scrap) unused PCB board, 1.5mm thick, approximately
50mm by 160mm
1 UV PCB-exposure-box (lamp mounted in a box with a glass
plate on top of which you lay your PCB, with a light-tight
cover) preferably with timer.
2 developer trays about 200mm by 300mm used to develop &
etch the PCB (make sure the tray resists all chemicals used)
1 small hand held drill to drill holes in the PCB; something
like a Proxxon or Dremel is fine.
3 drills, 0.6mm 0.8mm and 1.0mm. I recommend Hard Metal (HM)
drills as they last (if handled properly) more than 10 times
longer than High Speed Steel (HSS) drills.
1 metal ruler
1 "snap-off" knife which may cause burns or unwanted
dropplets of the strongly caustic NaOH solution burning your
skin or damaging your clothing. I prepare my developer solution
by putting one L cold water into a developer tray, and then
slowly "sprinkling" the NaOH pellets in it, evenly
covering the whole surface. Be carefull to completely dissolve
all pellets (stirring or agitating) because undissolved pellets
may cause local overdevelopment of the PCBs' sensitive layer,
leading to unusable PCBs. The developer solution can be used
to develop a few PCBs (3 or 4 at least), but I throw it away
after every batch.
Prepare etching solution either by dissolving Iron Chloride
pellets in warm water (about 50 degrees centigrade, about
as warm as you can bear for prolonged periods). Use about
1kg with 1 L water; use less if you need less. If you already
have previously prepared solution, heat it until it is about
45 degrees centigrade. DO NOT do this on a stove as it may
easily run out of control, but use the "au bain marie"
method with hot running watter from the tap. If you use a
previously prepared solution, you may wish to start heating
up this solution before you do anything else; if you make
fresh solution you may consider making it as the last step
prior to etching. Other methods of heating the solution exist,
you can for instance use a water heater normally used in aquariums,
but these are fragile, and if ANYTHING goes wrong, just the
slightest leakage of the water heater will result in a potentially
dangerous situation. Especialy water with salts dissolved
in it (such as the etching solution) conducts elecricity very
4. Manufacturing a PCB
Expose the PCB. If you're using a fluorescent UV source (TL)
you should "preheat" the tube(s) for at least two
minutes just prior to starting the exposure (preheating must
be followed by exposure within two minutes, otherwise you'll
have to preheat again).
Most PCBs come with a blue or black, selfadhesive protective
layer that must be removed before exposure and processing.
Peel this off carefully, not scratching the delicate UV-sensitive
resist layer, in subdued light. Most UV-sensitive resists
are not very sensitive to normal room lighting, but leaving
them out in full sunlight for a day will definitely spoil
them. Now pressing it firmly into the corner of the alignment
tool, between the two transparancies, put it on the glass
plate of the PCB-exposure-box. Put the sheet of black paper
on top of this, so that it completely covers the PCB, and
pressing the PCB onto the PCB-exposure-boxes' glass plate
(weighting it with a couple of books for instance), start
the exposure. Some PCB-exposure-boxes come with a foam-covered
lid, that can be clamped tight during exposure to ensure good
contact between the glass plate, the transparency and the
PCB. If your box has this construction use this instead of
the books method. After the exposure open the lid or remove
the books, remove the black piece of paper, flip the whole
transparancy-PCB-transparancy-pack over, making sure that
the orientation of the PCB with respect to the transparancies
is not altered, readjust alignment by firmly pressing the
PCB into the corner of the alignment tool, and put the piece
of black paper on top of tihs, completely covering the PCB.
Now expose the second side of the PCB using the method described
Remove the PCB and set it aside in dark place. Repeat the
procedure above for any number of PCB's you may wish to make.
After you have completed all exposures, remove the alignment
tool with both transparancies, put it on a flat table, flip
over the top transparancy (using the tape as a hinge). Both
INK sides of the transparancies should now point up. This
is important because these transparancies have a tendency
to become stuck to each other, and transfer ink from one surface
onto the other, when the INK sides of two transparancies are
in prolonged contact with eachother. If you're totally finished
with the transparancies you should remove them from the alignment
tool ASAP, as most selfadhesive tapes have a tendency to become
very difficult to remove after some time, especially in the
presence of UV-light.
The exposure time of PCBs can vary from brand to brand and
from lighting source to lighting source. YOU should experiment
using several small pieces of PCB and several different timings
to determine your combinations' optimal value. I find 2 minutes
15 seconds a good starting point (as a matter of fact, this
is what I always use, indifferent of brand and indifferent
of which of the two (different) exposure-boxes at my disposal
If you have a carefull look at the exposed PCB, you can see
the pcb traces in the resin coat as a slight discolouration.
This discolouration may either be darker or lighter that the
surroundings, depending on the brand.
Develop the PCB in the NaOh solution, stirring/agitating an
turning over the PCB at regular intervals. If the photosensitive
resin comes off totally (within a minute) your PCB is overexposed.
If nothing seems to happen (within 2 minutes), your PCB is
underexposed. If the resin partially comes off, and the traces
become much easier to see, chances are that you have a correctly
exposed PCB. One major problem with PCBs is that sometimes
a VERY THIN layer of photoresist still covers the PCB when
YOU think that development was complete. This invisible layer
of photorisist will however still resist etching! For this
reason I recommend leaving the PCB in the NaOH solution for
about two minutes after YOU thought the development process
was complete (nothing changes anymore). If the photoresist
comes off the traces during these two minutes, the PCB was
overexposed anyway (or you're using very bad quality PCBs
or your transparancies are too light). Bad quality PCBs can
be identified by the fact that there is no large exposure
range between an underexposed and an overexposed PCB. Normally,
using a very good quality transparancies (the photographic
films printshops produce), PCBs can be overexposed by more
than a factor two with barely noticable effects.
After development is complete rinse the PCB in warm running
water for at least two minutes to remove all NaOH traces.
Etch the PCB in the Iron Chloride solution. The Iron Chloride
should have a termperature of about 40 degrees centigrade
(can just be touched for prolonged periods of time without
being unpleasantly hot) for optimal performance. If the temperature
is too high you may spoil your PCB in one of two ways: strong
underetching of the tracks or deterioration of the photosensitive
resist layer. If the temperature is too low you may spoil
your PCB because the traces become underetched as well; this
is something curious i've not been able to figure out exactly,
but perhaps it has something to do with the orientation of
crystals within the metal, at low temperatures the lateral
rate of etching seems be higher than the normal-to-the-surface
rate of etching, causing underetching.to connect the ground
planes on both sides of the PCB together. If there is a slight
misalignment you can spot this, and use this information with
the other holes where such a misalignment would lead to damage.
Drill all holes with the correct size drill for that hole;
in this image the 0.6mm holes are identified by green crosses,
the 0.8mm holes by red circles and the 1.0mm holes by blue
squares. Apart from the 0.6mm holes in the GND planes start
with the 1.0mm holes, then the 0.8mm holes, and drill the
0.6mm holes last. This prevents you from accidently redrilling
a hole with a larger drill, which will very easily lead to
the drill become stuck and breaking.
If you use HM drills be carefull as these drills are VERY
brittle; dropping them on the table from as little as 100mm
height may cause them to break. The good thing with HM drills
is that these last (if properly handled) for more than 2000
holes, where the HSS drills will be blunt after 10 holes in
glass fibre based PCBs, and completely useless after 50 holes.
Be carefull not to excert any sideways forces on the drills
as these forces are the reason they break. If you have unsteady
hands and/or are unexperienced you should use the (well lubricated,
sturdy) "rig", as these prevent any sideways forces.
I prefer to use the drill hand held, and I've broken 2 HM
drills the last two years, both of them by dropping them.
This has not always been the case though.
Drilling is easiest if you place the PCB on a hard flat surface,
and hold it by the edges. this not only gives added stability,
but also reduces the risk of drilling into your own hand.
Make your mother-father-husband-wife-daughter-son-niece-nephew-dog-cat
and last but not least yourself happy by putting a piece of
scrap wood or cardboard underneath the PCB you're drilling
to prevent you from drilling through your pcb into your table.
Of course this piece of scrap wood/cardboard must be thick
enough to prevent any accidents.
Separate the PCBs after all holes have been drilled by using
the metal ruler and the "snap-off" knife. You do
this by placing the PCB on a hard flat surface, and inscribing
a line in the middle of the PCB with the knife along the ruler.
Do this several times, on both sides until you've cut about
halfway through the PCB. You can then easily separate the
PCBs by breaking them along the inscribed lines. You may find
that the knife becomes blunt VERY quickly (it is after all
cutting through glass), and that is the reason I use snap-off
knifes. Be carefull not to harm yourself or your tabletop
with the knife. After you've separated the PCB's and removed
any loose fibres (by carefully cutting allong the edge of
the PCB), you are ready to proceed to building the circuit.
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at a competitive price.
PCB Printed Circuit Board Sometimes abbreviated as PCB,
is a thin plate on which chips and other electronic components
are placed. PCB Printed Circuit Board is the component made
of one or more layers made of insulating material of electrical
conductors.In electronics, printed circuit boards, or PCBs,
are used to mechanically support and electrically connect
electronic components using conductive pathways, or traces,
etched from copper sheets laminated onto a non-conductive
There are a few modern approaches to PCB manufacturing like
PCB milling,laser drilling/routing,which uses a series of
production steps (drilling/ trace isolation/ cutting board
outline) to create single and multilayer boards on a single
machine.We specialise in PCB manufacturing services.Our PCB
manufacturing services are geared towards giving our customers
the best service.Making your own prototype PCBs
專屔屃 尓寠尛尟 層屜屧 尟尠尅尠 屌屇?!!!
See also the Easy_PCB site for making prototypes
and/or larger quantities PCBs at LOW! Prices!!!
From it I ordering all my PCBs (prototypes & production)
Interesting for radio broadcasting???
Click here to learn more!!!
Interesting on access control systems???
Click here to learn more!!!
Interesting on other systems???
Click here to learn more!!!
What this is all about
With this page I try to show you one method for creating
your own professional-looking PCBs. They say a picture's worth
a thousand words, so I used enough pictures and let them do
most of the talking.
Having a 20-year experience in making my own prototype PCBs,
and having tried dozens of different methods, I recommend
the method described on this page as the best, both in terms
of cost and overall effort. Although the use of a specific
unique product is required, this should not be viewed as an
advertisement. I have no connection whatsoever with the company
mentioned. However, I don't see why a good product should
not be talked about for what its worth. I have photographed
all the stages of the process for you to look at. Making Printed
Circuit Boards at Home
By Bryan Ackerly, VK3YNG
(Updated, 14 feb 2004)
3.3 Ink Jet printer and film
Best results seem to be from an ink jet printer. A laser jet
printer does not seem to give as good results. Through experimentation
the best combination seems to be using an Epson printer with
>720dpi resolution and the use of Epson film (part no S041063).
A box of this film (30 sheets) will set you back about $100,
but if used properly a full box will last a long time. There
are cheaper films available but they do not produce as good
results. Consider purchasing among a number of people to distribute
costs. This film is chemically treated to react with the ink.
Do not handle the film directly with your fingers!!! VERY
FAST & EASY PCB MAKING
by Jacques Brodeur VE2EMM November, 03
This page describes a new way to make PCBs with a laser printer,
water release paper and a laminating machine.
PCB drawing software.
Laser printer with a resolution of better than 600 dpi or
a laser photo-copier.
Water release paper.
Green TRF Film.
Modified Hot laminating machine.
320 wet sanding paper.
Transparent Green spray enamel.
Stainless & Copper cleaner powder.
DRAW THE TRACES WITH A PCB DRAWING SOFTWARE
My preferred software is Sprit-Layout form ABACOM in Germany.
Also check their sPlan schematic software.
It is for home-brew users as it supports only 2 sided PCBs,
but it is so friendly that you will be able to design PCBs
the first time you use it.
PREPARING THE COPPER CLAD BOARD
Clean the copper with the powder your wife use to clean her
copper and stainless pots and pans (LAGOSTINA Stainless &
Copper cleaner) from SEARS. Use warm water and a scrubbing
pad (Scotch Bright). Rub vigorously to prepare the PCB in
order to have the toner stick to it better.
Dry it with an old clean rag. Do not use a paper towel, it
contains silicone and leaves a residue.
Finish by wiping with Acetone or Alcohol to remove any trace
USING A LASER PRINTER, PRINT ON WATER RELEASE PAPER
This paper is available from PULSAR as TTS paper (toner transfer
System) and from DigiKey or from VE2JX in Montreal.
There are 3 precautions when using this type of paper:
Print only on the shiny side. Set the printer to its highest
Handle this paper by the edges with dry hands.
Never send a page through the printer if it got wet.
FUSING THE PCB IMAGE ON THE COPPER
The FUSING Technique: (hot); The objective is to make the
toner image stick to the PCB without using any glue or additive
to make it stick. With the application of heat for a period
of time with pressure, the toner will become tacky and stick
very well to whatever it is touching; a process called “fusing」.
This toner will be the resist.
PLACE the paper on the bare PCB board, toner on the copper.
PASS them between the rollers of the hot laminating machine
from PULSAR or a GBC 95P or H-200 laminating machine modified
to reduce its speed.
DIP the board with the paper stuck to it in water, the paper
will be released in about 1 minute, run some water over the
board to wash off any residual glue(release agent).
What is a PCB? Making a PCB