Galvanic Brass Etching

Overview

This is a neat technique to etch brass using electrolysis I originally saw on The Steampunk Workshop. I really liked the notebooks he made there and decided to make one for my wife. This is a much more detailed writeup of how to do the etching based on my experience

One thing to note is this is there are much better ways if you want an absolutely perfect etch(Such as using press-n-peel instead of toner or by building a CNC etching machine. For the notebook I wanted antique looking pieces with minor imperfections, so it didn't end up looking machine done.

Items Needed

• Brass Sheet
• Any magazine
• Metal Polish
• Some sort of metal grid and holder. I used rabbit fencing, but there are lots of other things that would work.
• Any straight piece of wood
• Distilled Water
• Sandpaper, fine grit and heavy grit
• Copper Sulfate(Root Kill). May also be Copper Pentasulfate
• Epoxy(Only if attaching to notebook)
• Scouring Pad
• Black Spray Primer. This was incredibly hard to find, not on Amazon(The site I pushed was just for example, I've not ordered from there). Spray paint will not work at all. I found some very Dark Grey primer at a K-mart but that was just luck. An automotive shop would probably be your best bet.
• Moleskine Notebook(Only if making a notebook)
• Naptha(Either paint thinner or lighter fluid)

Tools

• A way to cut metal, chop saw or mill would be optimal. I just used a Dremel with a cutting wheel.
• A *laser* printer. You cannot use an inkjet since it must be toner.
• Pliers
• Any sort of bucket or pitcher
• Clothes Iron
• Low Voltage High Amperage Power Supply. I used a very old computer power supply that was 5V and roughly 2A output, higher would have been better though.

Safety

• Copper Sulfate isn't particularly dangerous for people(Really bad for the environment though), but always wear Goggles and ensure proper ventilation.
• High current in water, be sure that your power supply is completely off(Many have caps that have to drain) before touching anything. Current can easily kill and wet skin offers little electrical resistance.

Cutting and Toner Transfer

1. Cut your brass to size with whatever tools you have. Clean one side thoroughly(Naptha works well) followed by a polishing and rough up the surface with the scouring pad. Rinse with water ensuring all cleaning chemicals are gone and then dry it thoroughly.
2. Take a page out of a magazine that has mostly white background and print your design on it with the laser printer. Remember it must be only black and white. Set it to the highest quality setting possible too.
3. Cut out the design you just printed and align it on the brass. Place your iron on the highest setting(Make sure if it's a steaming one there is no water in it). Press firmly over the printed magazine on top of the brass with the iron, keep it moving. I went for about 10 minutes for a 4"x4" brass sheet, which was probably overboard.
4. Take your bucket it and put a small amount of warm water in it(Tap water is fine). With pliers(Since it should be incredibly hot) drop the brass sheet/paper combo into the water. Let sit for about half an hour.
5. Rub off the paper, it should have pretty much dissolved. Try to get as much as possible, but if there is a small amount left it won't kill anything. Resoak as much as needed, patience is key. Be carefull using your nails or you may scrape off the toner.

    

Making the holder grid combo

This is somewhat dependant on what you have handy. Both the grid and the holder need to be conductive, the trick with the holder though is you only want the plate you attach to it to be charged. I used plastic coated rabbit fencing. I took two large roughly equal sized pieces. One I scraped most of the insulation off and folded it so there was more surface area. The other I scraped off only a select area(To make contact with the sheet) and then electrical taped other exposed parts. I used a wooden stick to hold both of them up over the bucket so I could move them closer or further from each other as needed(I've tried other methods but it's always more painful). One really important thing to note is that none of it touches the bottom of the bucket. A layer of brass dust forms on the bottom and you will end up with a short if they are too low down. I've had this happen, it ends up burning through the bottom of the grid.

    

Etching the brass

1. Mix the distilled water with the copper sulfate, make it as saturated as possible. I heat up the water so I can get more dissolved in.
2. Connect up your plate to your holder, make sure the holder has no exposed conductive parts.
3. Set up your rig in the bucket and position the grid and plate as close as possible without touching(About half an inch apart).
4. Pour in the copper sulfate solution(blue vitrol). The plate needs to be completely submersed.
5. Hook up the ground of the power supply to the grid, and the other end to the holder. The flow of electricity goes from the plate to the grid, carrying the brass with it as it goes.
6. The etching speed depends on how much amperage your power supply has, how much brass is exposed, how close your plates are together, how much copper sulfate you dissolved. At about 2A, 4"x4" plate, half inch away, and fully saturated water I was cleaning the grid and plate roughly every hour. I just run both over the sink. It took about 6 hours for a fingernail sized etch.

    

Spraying and Cleaning

1. When you are satisfied with the depth of your etch take off the plate and give it a good rinsing.
2. Remove the toner using naptha and the scouring pad.
3. Give it a quick polish, rinse it off thoroughly with water and then dry it completely.
4. Spray it with primer and let dry.
5. Evenly sand off the primer. The easiest way I found to do this was lay the sandpaper on a flat surface and run the plate over it. You want to only hit the peaks of the brass
6. Reclean with polish and any cloth or the scouring pad and you have your finished plate.
7. I went ahead and scrubbed with the scouring pad and polish till most of the toner was off. Leaving just an outline around where it was etched. Just depends on the look you are going for.

    

Making the Notebook

1. This is really simple just sand the back of the plate with heavy grit sandpaper. Then clean the notebook.
2. Thoroughly mix your epoxy and apply a thin layer on the sheet. Place on notebook, set something heavy over it. Clean the edges as epoxy gets squished out. Let sit about a day and you're done.