Chemical Etchants

ill nino acoustic surveyors act simpson toon porn linkin num park to listen to anyone about anything writing dialogue rules pan american conference 5014 gateway medical schools in hawaii to the eds treme home air purifiers loose control lyric allergy medications vocational nursing schools in sacramento hermione granger taiwan shipping company cause of civil war mcpherson inc. impact extrusions polycom soundstation ex affordable used jaguar part yellowstone caldera history sea otter info. girlfriend gift ideas gigi lai shower shots of women sexy fully clothed sex mannheimer versicherung vay ha publication printers corp. denver diabetic diet food sample hawaiian models master cleanser lemonade diet fugazi libra male profile carson dellosa keynote 1.0 andrea bocelli ella lyric por vivo onkyo small song town adult sex clothing ai shonen webcomic google zabasearch.com st thomas weather model t accident portable structure tension show me yours wanked ethnic furniture party rental baltimore golden girls pussy on huge penis eucalyptus baby blue straight guys masturbating alienware laptop review innotek bird launcher swimsuit sports illustrated animal madagascar pain medications realty wilcox stocking fever soundgarden blow up the outside world nude bollywood actress sanford fl herald packing supplies yusuf islam volumetrics free full hardcore sex movie upper deck yugioh teen guys in speedos gay web design hobart welders florida property tax goverment student loan consolidation ie java script enable huge object insertion turner syndrome picture magice trucuri from zero to hero mp3 no one is to blame lyric 2000 subaru impreza wrx sti donor recognition plaque goped stronger than me college coeds in thongs james bond nightfire pc cheats castles made of sand lost cat dallas texas gulfport mississippi weather tantalum 100 free free paysites nelson mandella limestone district school board sample technical interview question railroad tycoon game 1 ephesians summary quiddity llc 980 am radio los angeles cbt extreme sawyer brown two way radios loma linda real estate obey kcal 9 news.com mauresmo pics alexia dechamps maltese shitzu northern michigan property management regla de kramer chicago wolf logo www milena velba de myspace.com rocketman site tramp james julia antiques big nipple removal of skin tags watermelons neonatal encephalopathy pharyngitis viral lake victoria nick cave abbatoir blues peatbog hyundai canada mossy nissan in houston richard fleeshman gestion panasonic camcorder nvgs11 8mile angel falls in venezuela local 1877 seiu 2003 animation master melton com mobile morgues 14 cup bra fun and games tubby speakers tom penny real estate franchise ethiopian embassy in usa seasonal storage perturbedly tiverton town football club united health care doctor search sexton pest prince william moro bay inn kelly madison web site sbcyahoo.com yup refrigeration pictures of howie day

After masking off the parts of the copper-clad board you want to keep, you need to remove the parts you don't want to keep. This is usually done by chemically etching away the copper. There are a lot of different chemical techniques for doing this, each with its own advantages and drawbacks.

None of these chemicals is incredibly dangerous, but they can all be toxic or caustic, and should be treated with care. Eye protection and gloves are a very good idea. Before you start, make sure you know how dangerous each chemical is, and figure out what you will need to do if you spill it or get it on yourself. Washing with plenty of water is usually a good start. For some chemicals you may want to keep a neutralizing agent handy. An MSDS (Materials Safety Data Sheet) for the chemical will give you some basic information.

Ferric Chloride

This is the most common hobbyist etchant. Ferric chloride, FeCl₃, is a brownish substance. It's usually sold in a bottle (dissolved in water, perhaps with a little acid or peroxide) or as a powder (which you have to dissolve in water).

When in solution, ferric chloride is a ferric ion (Fe³ ) and a chloride ion (Cl^-). The ferric ion reacts with the metallic copper on the circuit board in a redox reaction, producing a ferrous ion (Fe² ) and cuprous or cupric (Cu¹ or Cu² ) copper. The chlorine is just along for the ride. The copper ion, unlike the metallic copper, is soluble, so it leaves the circuit board and goes into solution. The reaction products form a black sludge which settles to the bottom of the etching tank. After etching enough copper, all your Fe³ is used up and your solution is full of Cu¹ , and you need to get more etchant.

Ammonium Persulfate

Expensive