More pedal etching!

[trevorus]

Re: More pedal etching!

Another thing to do for the disposal is use some sodium carbonate to neutralise the acid leftovers. Sodium bicarbonate works also, but produces some hydrogen gas, so do this one in a well ventilated area as well, the result being NaCl and water (and H2...).

[ratherdashing]

Re: More pedal etching!

Etching is cool. I did it with the FTL Drive.

One other thing to keep in mind is that the chemical reaction produces three products: aluminium oxide (dark powdery precipitate), water, and chlorine gas. Aluminium oxide and water are harmless, and can (in theory) be disposed of in the sewer, as long as you don't have much leftover HCl in there.

Chlorine gas, however, is highly toxic. So much so that it's been used as a chemical weapon in the past. You should only ever do your etching outdoors or in a well-ventilated area (i.e. fume hood). A decent respirator is a good idea, and eye protection is also mandatory as the gas will burn your eyes.

I'm sure you guys are being very safe. I just wanted to post this here in case someone came along and decided to do this in their bedroom or something.

[misterwhizzy]

Re: More pedal etching!

So awesome. Loving these.

[CTN]

Re: More pedal etching!

I enjoy this thread for the cool visuals and because it makes my chemistry sense tingle.

[Surgeon]

Re: More pedal etching!

It's amazing how fine of lines you can get with the acid. I've been using laser toner transfer, but I really like the spray paint idea.

To get lines that fine, you have to use a weaker acid. I usually keep the fine-lined designs for batches of acid I've used once before. The process takes more time, isn't as aggressive and yields finer lines.

I've never managed to "recharge" my acid as many on the web claim to be able to (and I'm a chemist for dog's sake), I've tried a bunch of things, including buying a fishtank bubble-thingamabob to bubble air through my solution for 24hrs with no good results. You can add more h2o2 in there to replenish the H+ supply but then you dilute the acid too much and must add some more. Nowadays, I etch in batches with fresh solution, making as little as I can. Once I've used it twice max (more than that is pretty pointless), I neutralize it and mix it with cement. Once it's solid (little bricks basically), I send it to a safe "technical disposal" place.

[trevorus]

Re: More pedal etching!

Sorry Trev, don't mean to hijack your killer work...

No problem! I like seeing your different style, and it gives me some ideas to experiment with. It's amazing how fine of lines you can get with the acid. I've been using laser toner transfer, but I really like the spray paint idea.

[jon the art guy]

Re: More pedal etching!

It's really pretty easy. H+ concentration is based on logarithmic scale, so the 1-7 (and 7-14) range is easy to work with.

Sent from my chromed robot turd, using the miserable junk code known as crapatalk.

now that I'm interested in it and now that we have youtube in the world, I see it can be way easier than what I had to deal with. I saw one guy electro-etch a knife blade as well which took him a couple minutes, and I'm kind of liking that idea too.

[trevorus]

Re: More pedal etching!

It's really pretty easy. H+ concentration is based on logarithmic scale, so the 1-7 (and 7-14) range is easy to work with. I don't have a pH tester, but I'm sure it's pretty low on the scale. I just made sure to wear long sleeves, nitrile gloves, and goggles. I'm using only about 8 ounces of solution. It doesn't take much!

Sent from my chromed robot turd, using the miserable junk code known as crapatalk.

[jon the art guy]

Re: More pedal etching!

I wonder if my printmaking friends ever got into using stuff like this?

I have never attempted etching at home because I was the tech in a printmaking lab and had the distinction of having to dress up like Darth Vader and clean out the acid vats. The solution's ph is somewhere slightly lower than orange juice, but our professors made absolutely no bones about how people were blinded by the stuff. Ph gets more acidic in magnitudes, so a ph1 is what, 10x more acidic than ph2 or something. We were using 1.5-1.7 to slow-etch plates over the course of 8hr or so. Had to put of a thin layer of asphaltum and draw using a steel stylus. I haaaaated it so much and gave everyone the stink-eye when they wanted to do an etching.

[trevorus]

Re: More pedal etching!

Basically the same stuff as you'd use to do a PCB then I'm guessing?

Yes, but I keep the used stuff separate. I have some big glass jars I keep it in and reuse it until I have to neutralize it before disposal.

Sent from my chromed robot turd, using the miserable junk code known as crapatalk.

[Chris of Arabia]

Re: More pedal etching!

Ach! Probably total crap...

[trevorus]

Re: More pedal etching!

I'm sure I must have asked this before (probably of Surgeon), but what's the process for this?

Basically strong hydrochloric and, with a little peroxide in it to speed the oxidation. It eats aluminum and gets very warm. You have to absolutely cover everything you don't want to dissolve. (that includes your hands, eyes, etc.)

Sent from my chromed robot turd, using the miserable junk code known as crapatalk.

[Surgeon]

Re: More pedal etching!

I'm sure I must have asked this before (probably of Surgeon), but what's the process for this?

Tape or paint over what you want to protect then dump in acid (I use muriatic acid + peroxyde, I think Trevor does too).

Tape works really well. I also like to spray paint, wait an hour or two for the paint to get gelatinous and then scribe the design with a nail...works very well even when you can't draw to save your life (like myself):









Sorry Trev, don't mean to hijack your killer work...

[Chris of Arabia]

Re: More pedal etching!

I'm sure I must have asked this before (probably of Surgeon), but what's the process for this?

[TwilightOdyssey]

Re: More pedal etching!

Really looks great !