Monday, March 31, 2014

Cranking Through the Failures to Get to Success!

I spent this weekend trying to figure out how to transfer an image to metal for etching.
There is a lot of info on this online, many different methods and materials and ideas.  I’ve read/watched about 20 different tutorials on the topic. 
The etching process crosses over into a lot of different industries; jewelry making, crafting, printmaking, weapon-smithing, sign making, electronics (it’s how they make circuit boards!), and I’ve been exploring all of them in my quest to master this art.

The basic idea is to lay down a resist on the metal, which will protect the surface during etching.  The areas covered with the resist will not etch away, while the exposed areas will, creating a 3-D image. 
There are different ways to apply resist.  You can just freehand it with permanent markers or certain kinds of paint or ink.  You can stamp an image.  You can make a stencil cut from adhesive material, or use a UV photo process to make a stencil.

Or you can print the design with a laser printer and use heat to transfer the toner to your metal.  Since I have a laser printer and an iron, and this method seems to produce crisp transfers of intricate images, I figured this would be the best way to go. There are many ways that people have devised of doing this, and I tried just about all of them this weekend.

I tried laser printing my designs on regular copy paper, transparencies, glossy photo paper, matt photo paper, a special blue transfer sheet made especially for transferring images to metal, magazine pages ripped from a catalog, even the slick backing sheet you peel your Avery labels off of.

I tried ironing for different lengths of time, at different heat settings, using different pressure/motions of the iron, on top of different ironing surfaces.  I tried quenching the hot metal in cold water, and hot water.

Sometimes the toner didn’t stick to the metal at all.  Sometimes the paper moved during ironing, smearing the image.  Sometimes the toner melted too much and blurred the image.  Sometimes only bits of the image stuck.  Sometimes most of the image looked great, but one part was marred somehow. Sometimes the image would feather into the minute grooves made by sanding the surface to give the toner something to grip. Sometimes the paper left little fuzzy fibers on the surface of the transferred toner.

Saturday was a frustrating day.  None of my 30 or so attempts to transfer the laser toner to metal resulted in a satisfactory image.
It looks so easy in the tutorial videos!  Yeah, you just iron it on there – BING!!!  Perfect image transfer! 
For some reason, it wasn’t working for me.

One thing this taught me is that the tiniest speck of dirt or oil on the metal surface will screw things up.  And metal is surprisingly dirty, even when it looks clean.  Just the natural oils on our skin can cause problems, so you have to be super careful when handling it.  Sanding will cover it with microscopic bits that need to be cleaned away with dishsoap and/or Comet, rinsed, and then wiped with a cotton ball wet with acetone.  Or 2 or 3 of 4 solvent-soaked cotton balls, which come away black, even though the metal looks perfectly shiny!

By Sunday I’d gotten much better at cleaning the metal – considering I only had a few scraps of brass to practice on, and I had to clean off every horrible failure in order to make my next attempts.
I learned to use finer grit sandpaper to rough up the surface just enough to give it some tooth, but not scratch so deep that the toner to bleeds into the grooves.
I’d also discovered a few ironing techniques that seem to work best; what temperature setting didn’t overheat the toner, how to pre-heat the metal before laying down the paper and letting it sit there under a steady iron for awhile so it would stick and not move around, how long it takes to get the metal hot enough to grab the toner off the paper, how to burnish with the tip of the iron to make sure the entire image gets stuck to the metal.
Oh, and I realized that all of my designs are not, in fact, bilaterally symmetrical,so reversing the image is essential if I want my Om symbol to be facing the right direction.  Derp!

It’s kind of crazy how many little things can go wrong, and I think I must have experienced all of them.

But by Sunday night, I was getting an almost-perfect transfer.  Not quite perfect yet, but I will get there.

At that point, I set up my electro-etching bath to see if I could take the next step and make those toner images into impressions on the metal.

You can etch metal with acid, but after doing some research, I decided I was more comfortable with the saltwater and electricity method, which I already had all the materials for, and doesn’t involve toxic chemicals.

Yeah…that didn’t go so well, either. 
I ended up killing the first power converter.  It just died after about 15 minutes.  My husband hooked me up with another one, which is actually better since it has a switch on it, which is much easier to deal with than plugging and unplugging it.  This one has survived so far.

During my first attempt, I had two pieces of metal in there.  One of them started to etch (and turn copper-colored), the other didn’t.
Turns out I’d clipped the electric contact onto a part of the metal covered with tape.  D’oh!

After an hour or so, my test pieces had barely etched, and my saline bath had turned into a completely disgusting sludgepit.  Seriously – it looked like the Bog of Eternal Stench, though fortunately, it did not smell like it.
This is a normal thing – the sludge is made up of all the metal particles coming off the metal due to the electric current – it’s all SCIENCE and stuff, you can look it up.
But it looks pretty gross.
And when I checked my last test of the evening, the alligator clips that suspended the pieces in the solution and served as contact points had disappeared.  They’d just completely dissolved.   O___o

At this point I don’t know why my etching bath didn’t work right, but I have a couple of ideas. 

I forgot to use distilled water, which I read won’t prevent the etching from happening, but it can decrease efficiency.  Our tap water is pretty damn hard – serious calcium (and whatever else) deposits form on the Cat’s water dish in no time, so I know there’s gunk in it, which may be effecting things.  These chemical reactions are pretty sensitive to such things, apparently.

I have cleaned out my Bog (not down the sink!) and will make a new saline solution with the distilled water this time.
I will try a different method of suspending my pieces and connecting the electrodes (sturdy copper wire should do it).
I have cleaned my new test pieces and replaced the old masking tape (which maybe was gunking things up…???  I dunno.) that was on the backside with new packing tape, which is apparently fine.
And I will keep practicing my image transfer until I get those bitches perfect every time.

One day soon I’ll be totally awesome at this, and I’ll be using it to make beautiful things.
I can see them in my mind’s eye.  Just takes a little more effort to make them happen in reality.  And sometimes a lot of effort!

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