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Create custom etched aluminium (aluminum) art

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OK, you want a nice piece of custom artwork on your (insert project here), but have no idea how to make it happen?  This is the instructable for you!

In this case, I had made a set of handlebar riser extensions for my motorcycle and wanted something stylish to finish them off, oh, and also fill those nasty holes ...

This instructable is based in part on techiques I found on the web, plus some of my own experimentation.  A different approach can be found at: http://www.instructables.com/id/How-to-etch-aluminum-panel-labelsdesigns-with-a-r/

 
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Step 1: Things you will need

The first thing you need is an idea of what you want to achieve!  I wanted to make a couple of polished aluminium buttons to fill the holes in my handlebar risers, but you will probably want something different.  Basically, the thing that you are going to apply your etched artwork to has to be made of aluminium, or some other metal that will etch well with acid.

So, the list looks something like this:

- The thing you want to etch
- wet and dry sandpaper (various grades from about 100 to 1200 grit)
- Brasso or similar polishing compound (or a buffing wheel)
- A laser printer
- A sheet of printer labels, minus the labels (i.e just the waxed backing sheet that you would normally throw away)
- A clothes iron
- some sticky tape (sellotape or similar)
- a couple of facial tissues
- disposable (latex) gloves
- 2 small artists brushes
- nail polish
- Acid - hydrochloric or sulfuric (Lemon juice might work as well)
- acetone

 SAFETY NOTE:  Concentrated acids can be dangerous!  At a minimum, observe the following:

- WEAR PROTECTIVE CLOTHING.  Gloves and eye protection are a minimum. 

- ALWAYS WEAR EYE PROTECTION when working with dangerous substances such as acid. You only have two eyes, and they are very sensitive to any sort of injury, much more so than your hands.

- NEVER ADD WATER TO ACID.  If you need to dilute acid, add the acid to water.  If you splash water with a little acid in it, it won't hurt you, but if you splash acid it WILL.

- WORK WITH SMALL AMOUNTS and keep the bottle capped.  A small spill is easy to neutralise by flooding it with water.  A large spill will ruin your whole year!

- DON'T BREATHE THE FUMES.  The fumes from this reaction contain hydrogen and gaseous hydrogen chloride, both of which are bad to breathe in.

- Work on a flat surface clear of clutter, preferably somwhere you can flood with water if you need to.  A kitchen sink or a laundry tub is not a bad choice.

Alright.  Now that I've told you what not to do, let's get on with the fun stuff ...

Battlespeed2 months ago

Forgive one other comment. If you're interested in doing a lot of this kind of thing, you can make a fairly small investment in an etch-o-matic kit. With this, you create a stencil (using just about any art work) to do the etch, and then the stencil can be used repeatedly. I have no affiliation with this company.

http://etch-o-matic.com/index.html

mrwolfe (author)  Battlespeed2 months ago

Nice.

Battlespeed2 months ago

Why not just use lasertran or other laser transfer sheet?

mrwolfe (author)  Battlespeed2 months ago

Absolutely no reason other than I didn't have any. At the time I wrote this instructable, 3M "press n peel" was the only dry image transfer technology available here, it's expensive and not all that reliable. What I DID have was the wax backing paper from a sheet of A4 print labels and a laser printer. Any of the dry transfer etch resist products that are now on the market will work fine, probably with better results and less fiddling.

...sorry - that's "lazertran".

KRONOSS8 months ago
How long do I leave the acid on the metal surface
mrwolfe (author)  KRONOSS8 months ago
Not long. Maybe a minute or so. You don't get much acid onto the part with the brush, so it will stop reacting fairly quickly. If you want, you can give it a wash after a minute and have a look. if you think it needs more etching, just brush some more acid on it.
"Aluminum" isn't a word. Aluminium is an Element, 'aluminum' is what my plastic wallet from China Mall claims to be made of.
mrwolfe (author)  awesomecreations1 year ago
... which makes me pretty confident that you are from somewhere outside the USA :). Our American colleagues do love to have their own versions of things - language in particular. While I agree that the element is spelled "Aluminium" (Al-yoo-min-ee-um) in most parts of the world, and that I spell it this way because I'm from Australia, it is possible to buy more "aluminum" (Al-oom-in-um) than you can carry in the USA. In fact I have had discussions with American engineers who insisted that my spelling was incorrect, despite my argument that there is a similar material named "Titanium" (ty-tane-ee-um) that is strangely not pronounced "Titanum" (tight-an-um) in America. Mind you, the naming of the elements isn't exactly consistent (Molybdenum, Tantalum, Uranium, Thorium ...) Without these little quirks, I think life would be less interesting. Vive la difference`!
I hope you folks know that sodium hydroxide and aluminum produce hydrogen gas ... boom! I have done it. You are in danger :)
mrwolfe (author)  stringstretcher3 years ago
Yes it does, and so does hydrocloric acid (see the warnings above). For very small areas like this however, the amount of hydrogen given off is not sufficient to cause a flammable mixture, particularly with dilute solutions (CAVEAT: DO THIS IN A WELL VENTILATED AREA!).

If you want to use this for large areas, use dilute solutions (2:1 or 3:1 water to HCl) and do it in a well ventilated area to prevent the buildup of hydrogen.
sockless3 years ago
I think that Sodium Hydroxide would work too, since bases attack Al (this is why Al boats corrode). Now all I have to do is find a nice big piece of Al.
paqrat sockless3 years ago
You might try a newspaper if they do their own printing. Many use aluminum sheets. Our paper here sells their excess every so often.
mrwolfe (author)  sockless3 years ago
Yes it will work, and may be better depending on the effect you're after. As Kea says (elsewhere in these comments), immersing the part in dilute Sodium hydroxide solution is also known as poor man's anodising. It's not as good as electrolytic anodising in chromic or sulfuric acid, but it does leave a thick oxide layer where it reacts with the aluminium. I haven't tried concentrated sodium hydroxide solution, but I expect it will etch the surface as well.
Sweet, I might try that, since I have some 50% Sodium Hydroxide drain cleaner.
mrwolfe (author)  sockless3 years ago
The only problem with using sodium hydroxide to "anodise" is that you probably won't be able to colour it. Electrolytic anodising grows the oxide layer as an open cell structure that will trap a dye - hence take up a colour. By sealing the surface in boiling water, you can make the colour permanent. I doubt the oxide layer will grow the same way in sodium hydroxide. Worth a shot though!
kea3 years ago
Hydrochloric acid is also known as solder flux in N Z the brand name is Duzall in a green container. Aluminum can be sealed , called poor mans anodising by puting part in Caustic Soda for around 10 mins, how-ever the colour is not even. Cheers kiwi
mrwolfe (author)  kea3 years ago
I'm thinking I might have to have a go at using a version of this teqhnique to apply patterned anodising to an alumilium part.  Haven't tried caustic soda, I usually use sulfuric acid eletrolysis.
kea mrwolfe3 years ago
Yep; That is ture Anodising. Caustic Soda is poor mans Anodising. It seems to strip the grease off & stops further oxidising. Cheers kiwi
mrwolfe (author)  kea3 years ago
You can also put an aluminium part in the dishwasher prior to anodising it to clean it up and get any grease off it. Not good for polished surfaces though, because the alkali salts in dishwasher powder will leave a layer of oxide on it and make it dull. Different alkali, but the same idea as yours.
lazemaple3 years ago
If you want to try drawing freehand we use Sharpie Markers as a ferric acid resist - has to be Sharpie brand though. I haven't tried muriatic so not sure if it works for that acid or not. The Sharpie rubs off with rubbing alcohol when finished.
mrwolfe (author)  lazemaple3 years ago
I've used Sharpie markers as a patch-up resist on printed circuit boards.  I have found that you need to get a nice thick layer of ink down otherwise you can get patchy results.

Another possibility for freehand work is to apply nail polish with an artists brush.
andybiker3 years ago
When I made some badges from etched aluminium 30 years ago I used ferric chloride - it's used to etch printed circuit boards and should be available from most electronics suppliers. Maplin sell it in the UK. It etches very well with lots of bubbling. I would personally prefer this to sulphuric/hydrochloric acid as it's much safer. The ferric chloride does a good job of copper/aluminium/stainless-steel sinks and also my dad's concrete back yard. He wasn't pleased..... I think the warnings say to avoid contact with skin but I don't remember it being really nasty. It does mark your skin so you look like a 60-a-day smoker.
mrwolfe (author)  andybiker3 years ago
Yes, ferric chloride is REALLY messy stuff.  I've gone away from it for PCB's, I now use ammonium persulfate although there are some really nice instructables on using cuprous chloride (??).  I wasn't aware that ferric chloride etches aluminium though, thanks for the info.
arkie3 years ago
Beautiful work on a nice looking bike. mrwolfe (and kea) should be wary of the "anodizing" action of 'caustic soda'. Caustic soda is also known as lye or sodium hydroxide (or in the US, DRANO) and, in strong enough concentrations, will simply dissolve aluminum... with the release of potentially explosive hydrogen gas. The reason that aluminum, and chromium, stay so nice and bright is that they oxidize immediately on contact with the oxygen in our atmosphere. The really cool thing about the oxide layer? It's transparent! The transparent layer of oxidized (reacted with oxygen, or, in the case of iron, rusted) metal prevents any further penetration of oxygen into the body of your piece of metal. And, as mrwolfe has pointed out regarding acid, safety precautions apply equally to bases (the other end of the pH scale). If you touch sodium hydroxide with bare skin, a process called saponification begins: the inorganic base (lye) reacts with the fatty acids (your own personal skin!) and immediately starts to form soap. This is why your fingers will feel so slippery after touching lye. Get it off FAST! Under running water. Hope to see your future projects.
mrwolfe (author)  arkie3 years ago
Thanks Arkie.

Interesting, isn't it, that a really thin layer of oxide preserves the shiny appearance of metals like aluminium, and a thick layer (i.e anodising) can make it opaque and dull.
mslaynie3 years ago
That's really nice, and a custom bit of yourself to make your bike a bit more "you." I love being able to make my stuff less like everyone else's stuff. :D Thanks for such a clear instrubtable!
mrwolfe (author)  mslaynie3 years ago
You're most welcome :)
Can this be used to etch aluminum from cans or is that too thin and/or not the right flavor of aluminum?
mrwolfe (author)  wootwoot12343 years ago
Yes and no.

Acid will etch any grade of auminium, but cans usually have a protective plastic coating on them. You will probably have to remove the coating first.

If you wanted a pattern on the can, you could dilute the acid a bit to prevent it from going all the way through. Dilute acid will still eventually eat its way through the thin material of a can, but it will take longer, giving you some time to work and still be able to wash it off. Experiment!


As I have said, though, always add acid to water, NEVER add water to acid.
scicior3 years ago
I once had the not-so-great idea to use a spray can of oven cleaner to remove some sticky adhesive from an aluminum front panel I was trying to re-use. All that happened was the aluminum with no adhesive got etched! I wonder what's in that nasty stuff; it's been a few decades since I bought any...
mrwolfe (author)  scicior3 years ago
It's usually caustic soda (sodium hydroxide), which is also pretty good at taking anodising off aluminium as well.
servion3 years ago
Where can you get hydrochloric acid??
MRedmon servion3 years ago
If you have an ACE Hardware near you, they sell Muriatic acid (at something like 30% concentration) in smaller bottles for only $2.99. If you dilute it with hydrogen peroxide (like is recommended when etching PCBs) then it will last you quite a while.
mrwolfe (author)  servion3 years ago
Hardware or pool supply stores usually stock it. It's commonly used to lower the pH in swimming pools that are chlorinated with calcium hypochlorite (granular pool chlorine) or sodium hypochlorite (liquid pool chlorine).

Hydrochloric acid is also sold under the name "muriatic acid", which is typically used to clean concrete. You can also use sulfuric acid (battery acid, used in car batteries).

Although I haven't tried it, vinegar or lemon juice might also work, although not as well (you might have to leave it on for a while).

I think I'll have to do some more experimenting ... :)
n-brock3 years ago
Do you let the acid sit at all?
It sounds like you wash it off right away.
Also, how deep would you say the etch is?
mrwolfe (author)  n-brock3 years ago
I didn't really set it sit. There wasn't much exposed area and by the time I went over it a couple of times it had etched pretty well. For larger areas, I would suggest diluting the acid a bit because it will take you longer to cover the exposed bits. 

At full concentration, you will probably get an etch up to 0.5 mm deep, depending on how long you leave it on and how many times you apply the acid. On the part shown here, it's more like 0.2 mm.

Really, it's better to experiment a little on a scrap piece first to get am idea of how the acid behaves.
corey113 years ago
Huge problem that could maybe kill a person. do NOT use latex gloves with hydrocloric (muratic) acid!!!!!!!!!!! They won't last nearly as long as vinyl gloves. They may cost a little more but A) their reusable B) they last longer and C) your hands are A LOT more safe
mrwolfe (author)  corey113 years ago
Ah, I disagree.

According to Ansell who manufacture various types of chemical resistant gloves ( http://www.ansellpro.com/download/Ansell_7thEditionChemicalResistanceGuide.pdf ), natural rubber latex gloves have excellent resistance against concentrated Hydrochloric acid. Admittedly the test is for 0.48mm thickness, not the typical 0.1mm thickness of disposable gloves, but latex gloves WILL protect you from the acid as long as you don't go doing something stupid like dipping your hands in the stuff.  All bets are off if the gloves have holes in them of course.

Thicker gloves are better, so ordinary rubber washing-up gloves will also work, or if you REALLY want to be safe, buy a pair of thick chemical resistant gloves from a hardware store. Disposable gloves are just that, DISPOSABLE, so don't re-use them. 

There IS A WARNING about latex regarding allergic reactions in some people that can be quite serious. Generally, Vinyl is better because there isn't a problem with allergies, but LATEX GLOVES AND MURIATIC ACID CANNOT KILL YOU. 

As always, when working with dangerous substances BE CAREFUL and take steps to avoid accidents. I CANNOT STRESS THIS ENOUGH. Work in a clean, well laid out and well ventilated area, work with small amounts of acid and keep the acid bottle capped. Work methodically and avoid the fumes.
corey11 mrwolfe3 years ago
Well, that's what the workers at Lowes told me. But it was mainly a "I wouldn't reccommend it" kinda deal. We needed muratic acid because there is a lot of paint on our concrete floor on the back porch. So sorry about that. And if hydrochloric. Acid gets on your hands, and you don't get it off soon enough, the pain from it destroying skin could put someone in shock and kill them. But. Were talking about and hour or so, and I don't think some one would [intentionally] do that, but you never know. I would use and reccommend vinyl gloves but I can see some people may not have that option because of price, or the store not stocking them. But vinyl gloves aren't THAT expencive. Any ways, sorry for the inconvince.
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