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'''PCB''' is an abbreviation for '''printed circuit board''', the copper clad boards used for mounting and connecting electronic circuit components. Originally PCBs had holes for component leads, pins, wires, etc. which passed through and were soldered to the copper tracks on the underside. From the 1980s [[surface mount]] components have been used increasingly instead of through-hole components. Double-sided or multi-layer boards use plated-through holes, called vias to connect the traces on different layers. The most common PCBs are composed of either FR4 (glass fiber and epoxy), or the cheaper and easier to cut and drill but more brittle SRBP (Synthetic Resin Bonded Paper).<ref name="wpcb">[[Wikipedia:Printed circuit board]]</ref>
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.
==PCB layout design==
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==PCB fabrication==
Making PCBs at home is much quicker, with results the same day instead of waiting weeks for a commercial fabricator, and cheaper. However it involves working with messy chemicals, drilling will be tedious and the overall quality wont be as good.
==Etching and printing==
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==Tinning==
If you don't tin the board, coat the copper laminate with rework flux to prevent it oxidising.<ref name="mh">''[http://www.electricstuff.co.uk/pcbs.html How to make really really good homemade PCBs]'' by Mike Harrison</ref>
Tin-plating a PCB makes it a lot easier to solder. Use room-temperature tin plating crystals e.g. ''Seno Immerse Tin Crystals'', these produce a good finish in a few minutes but can be expensive. Only make enough tinning solution to cover a PCB in the tinning tray. Keep the solution in a concertina-type bottle to exclude air. Also avoid contamination with metals other than copper. Thoroughly rinse and dry the PCB before tinning. Use a separate tray and pair of tongs specifically for tinning, and rinse them after use. If the solution stops tinning, discard it, clean & rinse the tray, and make up a fresh solution. A cool tinning solution will usually prevent tinning so ensure the temperature of the tinning solution is at least 25ºC, but not more than 40ºC, put the bottle in hot water to warm it up.<ref name="mh"/>
Strip the etch resist thoroughly.<!-- acetone with toner or methylated spirits? --> Rub the copper surface with a plastic scourer until it is bright and shiny all over, wipe with a paper towel and immediately immerse the board in the tinning solution. Take care not to touch the copper surface after cleaning, as fingermarks will impair plating. Within about 30 seconds the copper should turn a silver colour, leave the board for about 5 minutes, agitating occasionally. For double-sided PCBs ensure the solution can get to both sides. Rinse the board thoroughly, and dry with paper towel to remove any tinning crystal deposits, which can spoil the finish. If the board isn't going to be soldered for a day or two, coat it either with a rework flux spray or a flux pen.<ref name="mh"/>
==Drilling==
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