Step 4: Etching the Brass

I mixed 1/2" cup of Root Kill with 16oz of water to make the etching solution. I only needed 16 oz with the plastic tub I was using. You might need to make more depending on your container.

Root kill solution is not something you want to drink but getting it on your hands is not that big an issue, unlike the Ferric Chloride acid used in PCB etching. It's designed as a product to go down drains, so when you are done dump it in the sink and run water after it.

Take your brass strip of 2" tall and 10"+ long and bend it around in a circle with the can of spray primer. It's not going to be perfect, just close to a circlish kind of shape is OK.

You need some way of applying the positive wire from the power source into the brass dice piece. I stripped a little bit off the top of the brass piece end where there is no paint. Using a scrap piece of 3/4" wood, I used popsicle sticks and a spade crimp connector to make something that would provide power to the brass dice when it's in the etching solution.

Put the dice piece into the tub and fill with etching solution until it's higher than the longest word (in this case, "three") and lower than the scraped off part on the end. The brass strip circle will displace some but not that much. Put that in and check the level again - I would put in and take out a plastic spoonful of etching solution at a time to get the height correct.

From the power supply, the ground goes to the brass strip circle surrounding the brass dice piece. The positive connection went into an automobile lamp to control the current. Testing showed the lamp burned at 955mA or so, so that's what the power would be at. Putting the auto lamp in series with the etching tank, run a wire from the auto lamp to the brass dice piece. When power is applied, brass moves though the etching solution from the positive (brass dice piece) to the negative (brass strip circle). This digs out the exposed bits (the words of numbers) and leaves the parts covered in paint alone.

How deep and how quick the dice gets etched depends on the current and voltage being supplied, how close the brass strip circle is to the brass dice piece, how much copper sulfate is dissolved into the etching solution, if it's before or after the 2nd Tuesday of the month and who won the last World Series. In other words, everyone's situation will be different.

I let it run about a half hour, turned off the power and pulled it out. It was covered in brown gunk that washes off easily but the etching wasn't so deep. I let it run another 30 minutes and checked again. A little more etching but not deep enough. In the end I determined that in my setup, it needed to run 2 hours to get the etching level I wanted.

If you are running it with a current limiter, check it every 20 to 30 minutes. If you are running it full bore, you might want to check it every 10.

The brown gunk that collects on the parts being etched washes off easily in water. Keep a spare tub with water nearby you can dump it in when you pull it out of the etching tub.

When you get an etched depth you like, pull it out and wash it off. Now it's time to scrub off all the paint.
Those look realllllly nice. But too bad I don't have the machinery to make them... :(
If you still want to make these, you could do it with just a hacksaw and a file really. The bar is bought hex shaped. Just hacksaw to length, etch it and then hand file the corners. <br> <br>Of course, you've probably got plenty more gear these days.
why not just use a file and screwdriver or something? may waste a lil more material by filing it, and the numbers may not be as precise cause you'r just chisiling it off, but it would be nice
Good idea for the etching solution, although I usually just use baking soda - that way my parents don't know that I'm plating/etching. My dad thinks that it puts off harmful chemicals, but hasn't read up on it and doesn't realize that it's the sodium chloride solutions that put off chlorine gas. Where can I get the root kill solution? And is there a specific brand? I'm only 15, so it may be conspicuous if I buy this in large quantities, seeing as it may easily be used as an explosive additive or used to make drugs. Most fifteen-year-olds don't have root-killing needs... Also, how much did it cost for the brass plate and the brass barstock? Honestly, my friend, I'm sorry that I'm asking so many questions, but this seems like a cool thing to make and I hope to do it right.
Very nice. Well documented, clear photos with marked up descriptions plus unique idea and perfect execution makes this an awesome Instructable. Who knew one could cut and etch metal like that in with modest home shop equipment? I remember as a kid I would take a crayon to my acrylic D&D dice to fill in the numbers. Then I'd buff it with a paper towel to remove the excess wax. I wonder if that would work to color the etched letters. I bet it would come out over time, especially if the dice are thrown.
to bad D&D dice are too hard to make out of metal. id try to etch brass 20-sided dice :D
One could use rubber or plastic material around the edges of each number to buffer it from glass or other hard surfaces...perhaps Liquid Tape (like normal electrical tape but in liquid form)?
my god that's beautiful. root kill for etching brass. wow!!!
First thing i said when I read this - &quot;that's cool.&quot;
Could you use Letter stamps to number the dice? &nbsp;(Words or Numerals)<br /> <br /> I made a&nbsp;pair&nbsp;of dice from 50mm (2in) cube mild steel. &nbsp;I drilled the dots then hammered in brass rod. &nbsp;I then sanded it flat and smooth. &nbsp;I then rounded the edges and corners. &nbsp;I made a second pair from 32mm cube (1 1/4 i think). &nbsp;Not i must say, to be played with on a glass top table.<br /> <br /> Nice instructable, i look forward to trying it.<br />
For the Brass Hex stock, McMaster-Carr [www.mcmaster.com] has a 3 ft piece for $28.92. Their part # 8952k123.
What is the power supply you are using, voltage, etc. What works best?
Epic Win on the name dude! it really caught my eye!
I have all on hand except the 1 amp 12V power supply. I have one 500 milliaps but can I then just run it for twice as long.
That should work. It's ok to pull the brass out of the solution to check it out. I generally do that and use a toothbrush to lightly brush off the crud that is building up on the dice themselves.
this... sounds naughty. it reminds me of the broiler boss on conker's bad fur day.
Awesome! I love it. Great idea, too! I need to make some.
OMG i want one!!!!!!11!!1!! shame you ran out :( i wouda bought like 50 of em :\ lol welp, thanks for the idea anyow :)
on the last step you mention using laquer and other finishes. From my good old metals class a few semesters ago, Turtle wax every now and then works wonders. also a more solid finish is a mixture of Flux paste and alcohol. Soak the piece in the mixture and then pull it out and light it on fire. the alcohol is burned off and the flux is sealed.
You should make a bunch of these and sell them on amazon for like $25 USD.
To the maker of this: You are GOD!!!! These are teh mosted awesomest thing I have ever seen!!!!!!!!!!!!
Just don't throw them too hard on a glass table, it would not be a great father's day present, the broken glass not the dice.
What type of primer do you use when making this? If it's an acrylic primer you can use spray oven cleaner, such as Easy Off, to dissolve the acrylic primer and paint. I use oven cleaner all the time when cleaning mold release and unsatisfactory paint jobs off my resin models. Spray thoroughly and let sit in a sink for 10-15 minutes, then scrub with a toothbrush while rinsing under running water. Works like a charm, though occasionally I will need to re-do the application if some bits of paint are being stubborn. From what I understand, oven cleaners should not be used with aluminum because it will pit the metal, but it possibly could work with the bronze. Just an idea. Love the dice though!
Can you etch steel plate that way?
Yeah. I have some examples of steel etched if anybody wants.
I'd like to see.
<a rel="nofollow" href="http://www.flickr.com/photos/13821724@N05/">http://www.flickr.com/photos/13821724@N05/</a> theres a link to my flickr where you can find the images of a book title plate I've made. It's a hunk of steel I shaped square on a grinder then masked by printing the negative on a sheet of glossy ink jet photo paper with a laser printer. Ironed on, then wetted off. Just to note, the pits in the metal are purposeful. <br/>
Wow! That's cool!
Thank you!
Nice work, haw deep is the final etch?
You have my favorite tool! The Veritas pocket square in the last step. So handy that when I thought I lost mine I called Lee Valley and asked why the don't offer it anymore. The guy said that they were selling it as having the same accuracy as a machinist's square but couldn't find a manufacturer who could consistently provide that. Dumb reasoning.
Soooo badass. Awesome and really thorough!
Here's an idea to make the lettering stand out more - glass. Get some glass enameling beads, super cheap... you can;t use an enameling kiln because the glass in the faces you have already done would slump out as you did the new sides... But if you use a torch to melt the beads it might work. Fill each side with a different color, or just with black glass on all sides for a classy look. Or maybe cobalt blue! Nice, shiny smooth glass, flush with the brass, or slightly inset. You would have to re-polish the brass after doing this because of scale from the heating.
Oh and I forgot, you have to use a chemical to treat the insides of the lettering to make the glass adhere, but that's cheap and easy, a bottle should be available and instructions should be available at any enameling resource. Check out Dick Blicks, or enasco.com for supplies.
Interesting idea. I might try that in the future - I do love art glass.
Should be fairly easy to try... the enameling beads are more like a powder - just fill in the letters and melt, essentially.
Those are pretty awesome but isn't it easier to cut a few squares and use a drill to make small indentions?
No. I don't have the equipment to make a perfectly square (to 0.001") piece of metal. I could make some sloppy rectangles but that wouldn't be the same. Besides, the "rolling log" style dice is different enough to count as funky.
It is simple but really creative + cool
WOW! Every man should have a pair! I want a pair and I'm not even a boy (named Sue). Although, on occasion, I've been told I had some. Obviously, they were confused. Probably flunked science class too. I was thinking one might need to paint them too. I have similar vision problems. I can't afford new eyeglasses Rx every year. I guess the reflection on the different surface types is enough. I know it's early but I think I see a sewing machine in your future.
Wonderful project, but there may be a problem. Since all six sides are etched to a uniform depth, and the words have different areas removed, the center of gravity of the die will be shifted, which will most likely lead to loaded dice. In this case, since the most material was removed from the 'three' side, that number will probably come up slightly more often than mere chance would dictate. If you're just showing them off, that's no big deal, but I wouldn't try gambling with them. Especially in rough company. However, if you used different fonts/sizes on each face, so that the area exposed to the etching process was equal, that wouldn't be a problem.
This is a totally thorough and impressive Instructable. Way to go!
Impressive product, impressive instructable. But if you're interested in extra legibility, I think that filling in the letters with ink/paint/enamel would help even more.
You are correct that filling in the etched parts with a gloss black would make it more visible. On this one, I cheated.<br/>My dad knew I was doing these dice for the contest, he didn't know he was the inspiration. So on my test piece (the botched etching job seen at my blog at:<br/><a rel="nofollow" href="http://www.whamodyne.com/2007/06/12/first-attempts-at-etching-brass-part-two/">whamodyne.com</a>) I painted in the etched parts with gloss black. By then I had some good pieces and showed him both and asked what he thought. He liked the unfilled ones, and seemed able to see them from afar, and thus I kept it natural.<br/><br/>
I figured you knew about using the paint (I recall von Slatt using paint in all his etching projects), but didn't quite know why you chose not to use it. Good reason, though--I imagine the dice do look better natural. I wonder if using a different font (outlines? black-letter?... well, maybe not for legibility) may work well with paint. Hrm. Though that would also necessitate new methods of applying the resist... I shall ponder this further!
I like it. They have a nice gold appearence, even though you used brass. is the randomness of a throw affected by the size or length of your lettering?
I doubt it. The piece weighs about 4.8oz overall and any amount of brass removed via etching is going to be tiny in comparison. Generally Brass Hex stock is accurate from the factory to about "0.005, but this is surplus hex I bought off ebay so it might be dinged up enough to make a difference. With practice, I'm sure you could get the roll you wanted with these guys, it's a matter of wrist action.
Those look totally sweet!
Yeah, JVS used the Vitriol(copper sulphate) for copper plating, salt water would work just as well for etching alone. ( I use DIY copper acetate for plating)

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