With my book fresh out on the market (and doing quite well, btw, according to the publisher. Thank you ALL who have ordered one. Your support and enthusiasm is overwhelming!!) I have learned of a little upset in the practicality of a few of the projects. This is a bit frustrating to both me and the publisher who has published quite a few books out there using this same process/product which is no longer readily accessible. I made extra effort to keep the supplies and materials used readily accessible to all for ease of working and project play.
So, here's the scoop. In my book I show you how to etch images/words onto meta (brass, nickel-silver, copper, etc) with a solution called "PCB Etchant" or "Ferric Chloride" (It's scientific name). It is produced for those making Printed Circuit Boards (PBC) and for years has been readily accessible at any Radio Shack for about $4.50. Suddenly (I know you love that word, Nina) :) Radio Shack doesn't carry it any more with no clear explanation as to why. I've talked to the corporate office and am getting little information. I'll be connecting with them again, that's for dang sure. It is available through Rio Grande (on this page) and, of course there are a few listed on ebay . Be aware that a haz mat shipping charge will apply and varies by company/shipper.
There is another alternative that works just as well - faster even - but it's important that you use caution with this method. (I'm one to not wear gloves or masks or goggles and will consider holding my breath a safety precaution - please don't bug me about this...I'm making changes. I know I need to be safer. But when using products such as muriatic acid, I'm more careful. The fumes are nasty.)
"Do what you oughta, add acid to water!" (I will repeat this and repeat this so's to make sure you don't forget it.) :)
One alternative is a muriatic acid/hydrogen peroxide solution. ONE part acid to TWO parts peroxide. (3-18 update: I'm so embarassed....I originally had the ratio written wrong here. I DID say "two parts acid and one part peroxide". A kind reader wrote and asked why her's didn't work after 7!!! hours. So, for those of you who have your arms in the air and stones ready for pitching my way, have pity on a middle aged, mother-of-two, hormonal lady).
Always add acid to "water" (any liquid other than acid, which, in this case is peroxide) . Remember the addage "Do what you oughta, add acid to water". It kind a rhymes so don't forget it! This solution etches MUCH faster than the ferric chloride. Two minutes in this solution will do what takes two HOURS in the ferric chloride solution. A little tiny bit goes a long way. I'll make up some comparison samples at some point here along with any other findings I come across.
"Do what you oughta, add acid to water!"
The peroxide used is regular drug store 3% which sells for about a buck a bottle. Muriatic acid is sold by the gallon at ANY hardware store for about $5. It's often used in swimming pools and is also sold for cleaning (i.e. acid etching) concrete. It's intense stuff in terms of fumes and, like any acid, gloves should be worn. Mix it up outside if at all possible. To neutralize the peroxide/acid solution, good ol' baking soda is the best. Make a small batch of water/soda solution and have it on hand to drop your metal piece in right after you remove it from the etching bath. Go a step further and use a toothbrush and straight soda to scrub the piece with. Let's hear it for sodium bicarbonate! What other products can be used in cake, housecleaning and acid neutralization! I occasionally brush my teeth with a wet toothbrush dipped in the powder- leaves the sweetest taste in my mouth! A workhorse of an element, I tell you!! :)
"Do what you oughta, add acid to water!" Got it? Is it burned in your brain yet? :)
According to the bottle of muriatic acid I have on hand, disposal is dilution with water and muriatic acid "before being poured in a sewer". That's what the bottle says. Here's the science of why it works:
Reaction of sodium bicarbonate and an acid:
- NaHCO3 + HCl → NaCl + H2CO3
This then decomposes into carbon dioxide and water:
Not so scary when viewed this way, eh?
Anyway, another option - because you are probably only going to be using a few teaspoons of this mix at a time - is to neutralize it with soda and then absorb it all up with paper towels. Let them dry outside and throw in the garbage. I live in a rural area with lots of dirt roads and not near a river or stream. I neutralize it and dump it in the driveway, but I only etch once every few months. For those of you in apartment buildings, this might not be a possibility for you so I'm still looking into more disposal options so I'll keep you posted. My dad has used it many times and says that all the cement guys (genius in their respective trades but not scientists) all neutralize it with a soda water (baking soda) and dilute it with thorough, long rinses with the hose -- Into the flower beds surrounding, say, an existing sidewalk. They do wear masks and gloves as a safety precaution if the have any sense.
Whooda thunk that in the year-ish it took for this book to come out, that the ferric chloride would be pulled from the market!?!?! In the end, the fact of the matter is that darn near all the projects in the book can be done without the etching and I''m hoping that there is enough information in it that you will all find plenty to play with still.