Root Killer

Well, I broke down and ordered root killer from Amazon. Two pounds for about $14 total. I couldn't face another day of scouring every home & garden store in the area in the off chance someone would have it. There was plenty of "new and improved safer" root killer stuff, but damnit, I wanted copper sulphate. Not that CS isn't safe on it's own, apparently it will "only" kill the roots in your pipes and according to one package, it's even found in pet food--but I'm not touching that last claim.

Also, I need to find a better method for image transfer. I attempted another etch but got as far as the transparency melting to the iron in one spot and incomplete toner transfer everywhere else before I gave over. The transparency isn't even opaque. I don't know if this was the printing or what but I'm kinda fed up.

Pocked and pitted

Guh! That was my first reaction to the etch. Haha, I kinda like how horrific it is though. That mad slashing in what should be the solid black/unetched areas is the result of using a Sharpie marker to mask off those areas -- but I'll begin at the beginning.

I printed out a test sheet of my chosen image. As per someone's recommendations, I spent a lot of time getting a pleasing halftone bitmap image. I say "a lot of time" because I'm just this side of functional with Photoshop. As it turns out I'm not sure the halftone thing was best. The principle is that the image is made up of many dots, each a solid spot of black, making the etch clearer. I really liked the effect below because it became a pattern of x's and dots. In other instances I can imagine I'd like a little more subtlety. More practice!

I went to my local Kinko's and made a transparency from my test sheet. I figured this was my best option. Since I don't own a laser printer, and I wasn't sure how far I could get in using off-schedule media in their copiers, I elected to use a transparency. As it turns out though, Press N Peel Blue, inkjet paper or glossy magazine pages may be an option for me because the employees don't really want to be bothered.

I went at around 4 o'clock pm and was stunned at how many people were out and about. Not just driving, but walking the streets and inside the store. This is because I work nights so most of my forays into the outside world occur at 12 am or later and thus are usually just include CVS and Denny's. It also reconfirmed how much I hate lazy parents. A woman was having an employee re-copy a photo of her son (?) in full military dress and her two children were actually wrestling on the floor just behind her. Ugh. EDITED TO ADD: BTW, how freakin' cheap is that? Your photo is so important, the first copy was just too green, why couldn't you have sprung for actual photo paper?

Anyway, then I checked out both Home Depot and Lowe's, looking for anything with copper sulphate in it. No luck. I keep thinking those places are so big they must be hiding cool stuff somewhere inside but I'm always disappointed. I'll have to try the smaller hardware stores in town. I'm just so fucking tired of buying things from the internet. I'm glad for the ease, the variety, the exposure to things I never would have found but sometimes I'd like to just be able to go to the store and get what I want that very day. EDITED TO ADD: Ha, as it turns out I can have 2 lbs. of Root Killer containing copper sulphate delivered to my home for $28.40

Then, I went to Barnes & Noble (are you detecting a pattern? I must live in suburbia) and checked out their clip art section. Some of the royalty/permission free books said any images may be used up to ten times for crafts and some of the newer books said something even more vague. I'm not anywhere close enough to consider selling anything but I though it'd be good to inform myself. I know a couple artists and I know how devastated they'd be if anyone was using their art without permission, not to even mention how they'd feel if someone sold it.

I gave that all up and went home. I cut out one of the images and after positioning it on the tin I set to ironing. I quickly saw that wasn't going to work. I have a blurred photo that was supposed to show that the toner wasn't adhering to the tin. I dumped out the water in the iron and cranked it up all the way past Linen. After that it seemed to go okay. The transparency melted just a bit but I pressed hard and smoothed it out for 2-3 minutes. I didn't get good coverage in the large black areas and attempted (unsucessfully) to substitute with Sharpie. Next time I'll try harder with the iron or give it up entirely. EDITED TO ADD: I also put electrical tape around the sides because I didn't want them to get etched. The sides have a black, sticky residue on them now.

I set up my workspace, the back doorstep, and this time reversed the process I had used to clean the tin from negative on the work piece to positive. I didn't like the way the paper towel had dissolved so I tried to use a piece of fabric but didn't like how that was trapping air *breathes* so I went back to the paper towel. The fabric was probably fine.

I left it to etch for a few minutes, and then five, and then five more. I was dissatisfied with the process, nothing seemed to be happening. And to make it even worse it seemed as though the Sharpie was coming off in the solution. Well, as it turns out there was just a film over the unmasked areas. This was probably plating from my unvarnished cathode because good god, I was definitely etching. Geez, I must have left it etching for 40 minutes.

I used steel wool to remove the toner and the film and revealed the first image. It's seriously pitted and kinda scary but I can't help but feel a little proud. Good thing I have another surface to practice on, huh?

A decision made

Ok, so I’ve come to a conclusion. I’ll use the Bordeaux etch method. Because it’s feasible. After following up in my research of the different types of “safer” etch methods, I hunted around for supplies. Because that’s truly the deciding factor here, availability and price. The Edinburgh etch method requires ferric acid, described here as “[a] somewhat water-soluble salt of iron and hydrochloric acid that has a tendency to become basic.” I wasn’t wild about the inclusion of hydrochloric acid but the author claims the method is non-toxic. That’s great but the Edinburgh etch requires a bit of a background in chemistry, including prepping the solution for use, beyond adding one part to another—and then purchasing test strips to determine the optimum strength.

Um, no thanks. According to Von Slatt, all one has to do is add a lot of Root Kill to a tub of water and then hook it up to a battery. So, the Bordeaux etch it is. It requires copper sulphate which is available in the gardening department as a root killer or as a spray to combat mildew. Cedric Green argues against using a solution like those I just mentioned because they contain additives but upon reviewing Von Slatt’s results, I’ve decided his method is good enough for me too. I'll just try to find a nearly pure copper sulphate product.

If I want to etch mild steel (iron) and zinc I can add an equal quantity of salt and if I want to etch aluminum I add an equal amount of sodium bisulphate. After another Google search I found this to be used for pool maintenance and is commonly referred to as “dry acid” because it’s, well, not liquid.

Beyond this, I found out that all metals involved in the etch must be of the same type otherwise it’ll become electroplating rather than etching. So, varnishing components may be in my future. I’m still going to try a salt water etch, because I’m already set up for it. I hope to do that tomorrow.

Beginnings

So, here are the results of my first attempts at etching metal. Not so great, huh? I used an Altoids tin and the salt water etch process I found at the Steampunk Workshop and Instructibles.

Actually, these are just the results of electrolytic cleaning as described here. I didn't even get to the etching before giving up. You'll see why towards the bottom of this post.

I followed a link in the comments of the Instructible above. Following his statement that electrolytic cleaning was easier than scrubbing at the tin, or stripping it with paint strippers I decided to forgo my own testing and just use the electrolytic cleaning.

Yesterday, on my day off, I took off to Ace Hardware and bought insulated alligator clips, electrical wire and a metal plate to act as the electrode. But not before I was called "a pretty girl" at least once. I've just found over the years that it's better to smile your thanks and then get on with whatever it was you were doing, rather than raising a fuss.

Then, I went to Target and bought a plastic container in which to put the solution and a lantern battery. I found one packaged with an underwater flashlight for $4.99 and individual batteries for $7.99. Go figure.

I mixed the solution, 1tbsp of household salt in enough water to cover the tin and poured it into the plastic storage container. Then, I put the metal plate at the bottom and folded up some paper towels to separate the tin and the plate to prevent a short. Once everything was in place and then connected I sat back and very impatiently waited. Every few minutes I'd disconnect the circuit and remove the tin to scratch at it. I don't know if this had any effect on the process but I couldn't resist. I didn't time the process but it'd taken enough time already that I didn't feel it was cost-effective to continue. Cost-effective meaning I got bored and would rather just purchase plain metal tins.

Also, another worrying side-effect of the process was the hazardous waste. Here's a picture of the solution today. I had it covered so the sediment got stirred up when I removed it. That floating white square is the paper towel and actually provides a good backdrop for the foul concoction. Good christ! If this is the result, I'm doubly certain I'd rather just purchase metals tins.

As you can see above, the tin is extra spotty because I didn't immediately rinse it and then dry it with heat. That's actually rust that formed incredibly fast in addition to the paint/enamel that I didn't completely remove. I read about that process here. That guy is primarily concerned with cleaning old engines and the like, but if Offlogic could use the process, I figured I could too.

Wow, I just remembered another reason for not doing this again. I'm not sure what it is I've created here other than that it's hazardous. It's some sort of chloride-something-or-other but I'm not sure what sort of metal Altoids tins are and what the metal plate I used as an electrode was made out of. I may just use another etching method like Bordeaux, Edinburgh, or Saline Sulphate . Those sound like the solution lasts longer, ultimately resulting in less waste.