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This article aims to be a guide to quickly and efficiently producing consistently high quality homebrew PCBs. The cost of materials is of secondary importance.<ref name="mh">''[http://www.electricstuff.co.uk/pcbs.html How to make really really good homemade PCBs]'' by Mike Harrison</ref>
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==PCB layout design==
===Best Practices===
==Bill of materials==
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Alternately take a straight edge and secure it along the line to cut. Then take a chisel (one set aside for this), and run one of the corners along the straight edge. First pass go lightly to just get a bit of a groove dug in for the tool to follow so it wont jump out on subsequent passes. Next pass or two press hard, and dig in for a deep groove. Score on both sides. Secure the board and snap the piece off. To finish the edge make a pass or two along it with a fine file.<ref>[http://www.eevblog.com/forum/manufacture/cutting-fr4-boards/15/ Cutting FR4 boards], EEVblog forum, August 2012</ref><ref name="diyaudio"/>
==Printing and etching==
There are two methods to choose from, the toner transfer method is cheap and
===Toner transfer===
Using a laser printer or copier, this does not work with an inkjet printer, to print an image of the PCB tracks on glossy paper. Laying this printed side onto the de-oxidised and de-greased copper laminate and using an iron at a high temperature, on the rear of the paper to transfer the toner from the paper onto the copper. After soaking in water to remove the paper, the toner now transferred to the copper laminate acts as an etch resist.<ref>[http://fullnet.com/~tomg/gooteepc.htm ''Easy Printed Circuit Board Fabrication, Using Laser Printer Toner Transfer''] by Thomas P. Gootee, 2007</ref> This can also be used to print component side parts and legends. ''Press'n'Peel'' is similar to this method.
===Photo resist===
Print the PCB layout onto clear or translucent film - this is the ''mask''. Plastic transparency might deform from the heat of the printing. Place the printed side against photo-resist coated PCB and expose to ultra-violet light. Pre-sensitised
===Etching===
Etching the PCB in Ferric Chloride (FeCl<sub>3</sub>) solution removes the copper not masked by the etch resist. Take precautions because FeCl<sub>3</sub> will deeply stain anything it comes in contact with.
===Safe disposal of FeCl<sub>3</sub>===
FeCl<sub>3</sub> is toxic and harmful to the environment - do not flush spent etchant down the drain. After use leave the FeCl<sub>3</sub> to stand still for at least a couple of days, the copper precipitates to the bottom, leaving still useful etchant on top. Pour this into another container. Add pure sodium bicarbonate (NaHCO<sub>3</sub>) aka baking soda to the thick mud at the bottom. The NaHCO<sub>3</sub> will react with ferric chloride rendering the solution relatively harmless to the environment. Do only a little bit at a time, waiting for the reaction to settle down each time. The reaction will produce a substance 7 to 10 times the volume of the solution, any spillage will contain still active FeCl<sub>3</sub> that will stain whatever it comes in contact with. Keep adding the NaHCO<sub>3</sub> until the rust-coloured mess is fairly dry in texture. It can then be disposed of along with the household waste.<ref>[http://www.diystompboxes.com/smfforum/index.php?PHPSESSID=2721ef0370b6f7ad578168a1c3200a26&topic=50426.msg377103#msg377103 Re: how do you all dispose of Ferric Chloride?] by Mark Hammer, 15 October 2006</ref>
===Alternative etchant to FeCl<sub>3</sub>===
Cupric chloride etchant is very similar to ferric chloride, but is simple to regenerate and there are no disposal problems.<ref>''[http://www.xertech.net/Tech/CuCl_ech.html Etching Circuit Boards Using Cupric Chloride and Acid Solution]'' by Stephen Kasten</ref>
==Tinning==
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==Drilling==
Use a drill press and a drill with a collet not a chuck. A 0.75mm drill bit will suit most holes and a 0.9mm for headers.
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==Commercial PCB fabricators==
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== References ==
{{reflist}}
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*[https://wiki.london.hackspace.org.uk/view/Project:Deactivating_a_ferric_chloride_solution Deactivating a ferric chloride solution]
===Commercial fabrication===
*ladyada.net wiki: [http://www.ladyada.net/wiki/tutorials/library/pcb/manufacturers.html? Where To Have Made]
*[http://pcbshopper.com/ PCB Price Comparison], a calculator showing the prices for prototype PCBs from different manufacturers
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