Create Custom Etched Aluminium (aluminum) Art

Intro: Create Custom Etched Aluminium (aluminum) Art

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: https://www.instructables.com/id/How-to-etch-aluminum-panel-labelsdesigns-with-a-r/

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 ...

STEP 2: Make Your Part

You will need something to etch.  I made up a couple of aluminium buttons from round bar, then sanded and polished the faces,  You don't need a buff to get a good polished surface, but it does make it a LOT easier! 

It is also worth noting that you don't HAVE to have a hightly polished surface, but the surface should be fairly flat and even and without gouges and large scratches.

To get a nice mirror finish by hand, rub the part down with wet and dry sandpaper going from coarse grit (100 grit or so) through successively finer grits till you get to 1200 grit.  Clean the part between grits to avoid scratches, and rub each finer grit at an angle to the previous one.  When all the previous grit marks are gone it's time to clean the part and move on to the next finer grit. 

Once you have reached 1200 grit, use some brasso or a similar abrasive cleaning solution to polish the part.

If you have a buff, the process is a lot quicker.  rub the part back with 600 grit then 1200 grit, then use a sisal buff to cut and finally a cloth buff to finish.  As before, clean the part with acetone or similar between grits. 

STEP 3: Create the Image

Now, to find an image to emboss our part with!  I found a picture of a wolf that looked like it would be a good starting point.  Using the GIMP image manipulation tool (you can download it for free). I reduced the image to black and white, then used MS Paint to clean it up and turn it into a logo.

I then reduced the size of the image and made up an A4 sheet of logos using Open Office Impress.  You can use powerpoint, or word, or staroffice, or any one of a number of programs to make up the sheet.  I turned the page ruler on in Impress so that I could reduce the image to the right size, then duplicated the logo a number of times until I had a sheet full.  You will want to print a sheet of images out because you probably won't get the next step (that's step 4)  right the first time.

Next, I took the backing from a sheet of printer labels and removed the remaining sticky paper (the sticky paper bit between the labels).  The labels themselves had been used for a bulk mail-out, and the waxed paper backing was left over.  Normally the backing paper would go into the bin, but I saved it for exactly this kind of thing.  Leave a strip (about 1/4") of the sticky paper on the top of the page for the laser printer to grab onto, but remove the rest.

Now print the image onto the waxed side of the backing sheet, as if the labels were still there.  The toner will form a nice image on the waxed paper.  I found that a colour laser is better for this, but if you only have a black-and-white printer, turn the toner density up as high as it will go.  You may be able to do this from the printer control menu when you print the images, or you might have to set the toner density from the front control panel onthe printer.

STEP 4: Transfer the Image

Now that you have some images to play with, cut one out of the sheet and place it face (toner side) down on the part.  It helps to secure the paper in place with some sellotape or something similar.  Electrical or duct tape is going to be too thick.  You want just enough tape to stop the paper moving as you set the iron up.

Put some facial tissue over the button AFTER you have taped the logo down.  The slight sponginess of the tissue will help to even out the pressure on the paper and ensure the image is evenly transferred.  Now turn the temperature setting on the iron to full and sit the iron on top of the tissue.  You will probably have to do a little experimentation to determine the optimal amount of time to leave the iron on.  Too long and the image will bleed and go fuzzy, too short and the toner won't transfer fully.

I sat the iron on the button while it was still cold, then turned it on and waited for it to heat up.  Once the red "heating up" light on the iron went out, I waited another 10 seconds or so then took the iron off and let the whole thing cool.

STEP 5: Touch Up and Etch

After a few attempts, I got a transfer that wasn't too bad.  I used some nail polish and a small brush to cover those areas where the toner had not transferred well, and a scalpel to clean up some other areas where the toner had bled a little bit..

Once the nail polish is dry, use a small brush to apply the acid.  BE VERY CAREFUL, acid is nasty stuff and will ruin your day along with your clothes.  Only work with a small amount at a time and avoid breathing the fumes.  There's no real need to work quickly, so take your time.  Once the acid has been worked over all the areas that you wish to etch, wash the part off with lots of water.  The chemistry is something like:

2Al + 6HCl => 2AlCl3 + 6H2
2AlCl3 + 3H2O => Al2O3 + 6HCl

I used full strength acid on this part, but you might want to dilute the acid 1:1 or 1:2 with water, particularly for larger areas. 

WARNING!!  
When diluting the acid, always always ALWAYS add the acid to the water, NEVER the other way around. If you splash water with a little acid in it on yourself there's no real problem, but if you splash acid with a little water in it on yourself, you will be in a world of hurt.  Some acids, particularly in very concentrated form, react violently when water is added to them. Adding the same concentrated acid to water does not cause the same violent reaction.

WEAR EYE PROTECTION!

Once you have etched and washed the part, dry it and clean the toner and nail polish off with acetone.

If you like, you can now use some automotive clear coat lacquer to give it a weatherproof coating. 

STEP 6: Enjoy!

This is the finished article installed on the bike.  Nice, huh?

Comments

[Battlespeed]

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]

Nice.

[Battlespeed]

Why not just use lasertran or other laser transfer sheet?

[mrwolfe]

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.

[Battlespeed]

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

[KRONOSS]

How long do I leave the acid on the metal surface

[mrwolfe]

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.

[awesomecreations]

"Aluminum" isn't a word. Aluminium is an Element, 'aluminum' is what my plastic wallet from China Mall claims to be made of.

[mrwolfe]

... 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`!

[stringstretcher]

I hope you folks know that sodium hydroxide and aluminum produce hydrogen gas ... boom! I have done it. You are in danger :)

[mrwolfe]

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.

[sockless]

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]

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]

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.

[sockless]

Sweet, I might try that, since I have some 50% Sodium Hydroxide drain cleaner.

[mrwolfe]

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!

[kea]

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]

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]

Yep; That is ture Anodising. Caustic Soda is poor mans Anodising. It seems to strip the grease off & stops further oxidising. Cheers kiwi

[mrwolfe]

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.