Introduction: DIY Metal Etching
Have you ever seen or witnessed industrial metal etching that uses lots of harsh chemicals? Ever wanted to achieve the same results but never knew where to start? Well guess what, you can achieve the same results by using a couple of things that you probably already have in your house with this simple project. No harsh chemicals. Lots of fun!
Metal etching is an awesome technique that carefully removes the top layers of metal to create a visible shape. It's a great chance to be creative with different shapes and writing and transferring it onto whatever metal objects you want. Knives, metal ornaments and tools are just a few objects you could etch using this technique.
Let the fun and creativity begin...
Warning: This process of metal etching releases harmful gases that you must never inhale. Always etch metal outside or in a extremely well ventilated environment and use appropriate safety equipment (extractors, respirators etc) to reduce the chance of inhalation. This project also uses low voltage electricity in close proximity with water. Take care to ensure the two don't mix. I take no responsibility for injury or damage to property as a result of your mistakes when attempting this project.
Step 1: Gather Parts
There are a few things required to etch metal at home:
- 1x Tub of table salt.
- 1x Roll of electricians tape.
- 1x 12 volt power supply (Mine is from a computer. Batteries do work however they are a lot slower and they can drain very quickly during the process).
- 1x Short length of wire (about 40 cm will do, it doesn't have to be exact).
- 1x Small tub (for mixing the salt solution in).
- A few sheets of kitchen paper or a cloth.
- 1x Piece of metal to be etched.
- 1x Respirator (protection from the gases released during the process is essential).
- 1x Pair of gloves (once used, the salt solution can be quite irritating to skin).
- Access to warm water
- 3x Cotton buds (the kind you use in the bathroom that have a stick with a small amount of cotton on either end (pictured))
- Scouring Pad
There are a few tools required to etch metal at home:
- Wire cutters or scissors.
- Spoon (or something to mix the salt solution with, I used tweezers).
- Tablespoon (to measure salt).
- Stanley knife or craft knife (to cut out your design).
- Pen (to draw out your design).
- Small measuring jug (it can be something from the kitchen as it will only be used to measure water. It will not be damaged during the etching process).
Step 2: Prepare Salt Solution
Put on your gloves to protect your hands. I found the salt solution to be quite irritating if left on your skin.
Salt solution is required to easily conduct electricity and help remove the metal during the etching process.
To make the salt solution, do the following:
Firstly, put a small amount of WARM water in the tub (about 50 ml will be enough). It has to be warm because the salt dissolves easier in warm water.
Next, put about a tablespoon of salt into the water and stir it thoroughly.
Step 3: Prepare Cotton Bud
To get the cotton bud ready for etching do the following:
Using the wire cutters, remove the insulation from the short piece of wire. About 2 cm should be exposed.
Next, secure the wire to the head of the cotton bud by twisting it around the cotton. Make sure the wire is around the cotton head and not the stick in the middle.
Remove the insulation from the other end of the wire so it can be connected to the power supply.
Step 4: Mask Metal
In this step you will be able to be creative to produce whatever design you choose. It could include shapes, text or patterns. As long as you can cut it out, you can etch it into the metal!
Cut enough strips of electrical tape to cover slightly more than the area you want to etch. Stick the strips to the metal making sure they slightly overlap. Press down hard to ensure a good seal to the metal surface.
Draw your design onto the tape using the pen and then cut it out by using your craft knife of Stanley knife.
Step 5: Connect Everything Up
To get ready for etching you will need to get everything connected up:
First, attach the crocodile clip to the metal and then connect the wire from it to the positive of the power supply.
Next, connect the cotton bud to the negative of the power supply.
See the diagram above if you have trouble figuring it out.
Awesome, your ready to etch your metal!
Step 6: Etch!
This step is where the magic really happens!
Put your respirator on now.
To get etching, first dip the head of the cotton bud into the salt solution that you made in step 2. Let the solution absorb into the cotton for at least 10 seconds.
When you are ready, turn on the power supply and touch the salt solution soaked cotton bud onto the metal where it is to be etched. It should start fizzing within a few seconds and a whitish looking gas will start to emerge in small quantities. DO NOT BREATHE THIS IN! You will also notice a bit of heat. This is a normal part of the process. If none of the above happens then please see the troubleshooting section in step 9.
This process will probably take at least 10 minutes for a small design, so take your time. It may look like the etching is complete when the metal turns a dull grey colour but keep going until all of your design is a dark grey.
Move the tip around your design SLOWLY and make sure you give everywhere an even amount of time to etch. Make sure to keep dipping the cotton bud in the salt solution about once every 30 seconds. You will notice that after a short while the metal starts to darken and the tip of the cotton bud slowly turns to a deep black colour (pictured). When this happens it is a good idea to refresh the cotton bud by simply untwisting the wire and twisting it back around the fresh cotton bud (as in step 3). Soak the fresh cotton bud for 10 seconds and then continue.
Also, keep wiping over the design with a cloth or kitchen paper every few minutes to get rid of any of the mushy cotton that comes off the cotton bud and any excess salt solution.
Warning: Make sure only the cotton touches the metal and not the wire twisted around it. If the wire touches the metal, then this is effectively a short circuit and could damage your equipment. Do not breathe in the gas that is created during the process. Make sure you are in a well ventilated area (i.e. outside) and that you wear your respirator.
Step 7: Reveal Etching
When all of your design has turned a dark grey and you have finished, make sure you turn off your power supply.
Wipe over your design with a cloth or kitchen paper.
Slowly peel off the tape mask to reveal your etched design.
It may look a bit dull at the moment but don't worry - in the next step we'll clean it up.
Step 8: Cleaning It Up
To make your design look bright and shiny, take your scouring pad and rub over your design in a circular motion. This will remove the dull coating and make the metal look nice and shiny!
Step 9: Results and Troubleshooting
Congratulations, you've just etched metal at home!
Check out the project video here
Q. When I put the tip of my cotton bud on the metal nothing happens. It doesn't fizz, release and smoke looking gas or change colour. What am I doing wrong?
A. There could be a few things wrong:
- Your circuit isn't complete. Check that the wires are making proper contact with the power supply leads and make sure that the crocodile clip is properly attached to the metal with good contact. Check you are getting voltage from the power supply by either using a multi meter or by connecting something rated for 12 volts to your supply (the fuse in your power supply might be blown).
- You have connected the wire for the cotton bud to the plastic stick in the middle and not the soaked cotton on the end. Move the wire to the cotton so it can conduct electricity through the salt solution.
- You haven't soaked the cotton bud in the salt solution. Soak for 10 seconds and then try again.
Q. I'm trying to etch aluminium. Why does it take so much longer than steel?
A. Due to the conductive and physical properties of aluminium, it does take longer than steel but with a bit of patience the results will be just the same. It could take up to 2 or 3 times longer than etching steel does. So just be patient and you'll achieve it eventually.
If you have any other problems while trying this awesome process please comment and I'll do my best to help you out!