I am a sword and knife enthusiast who always found the little etching on the side of my weapons super cool. I searched the web for several ways to make my own etchings on my weapons. To my dismay, there were few methods that did not contain harsh, dangerous chemicals that I didn't have at that time.Then a little spark of light appeared to me in the form of salt water etching! This method contains a few household items that are readily available and cheap.
WARNING: This method produced a harmful gas that should not be breathed in. Please use in a well ventilated area.
Step 1: Items Needed
All the items that are needed can be found around the house or for cheap elsewhere.
Blade (steel works best, stainless or carbon)
A pair of alligator clips
Alcohol or Windex
Nail Polish (optional)
Some Artistic Ability
Step 2: Cleaning/Mixing Salt and Water
Take some alcohol or Windex and clean the blade thoroughly. This helps the process go smoother. Also make sure the alligator clips, battery, and all other necessary components are clean and functioning properly.
At this time also mix the salt and water. I find that using one tablespoon of salt per cup of water works pretty well. Warm water makes the salt dissolve quicker. Remember, you don't need much salt water.
Step 3: Plan and Execute
This is were you need a little artistic ability.
If you plan on making pretty simple geometric shapes you can use only electric tape. If you plan on doing any other shape with curvy lines and whatnot you can use nail polish (I've also heard that Sharpie works too, but I have not tried that).
If you feel you cannot do that you can go to any local print shop and ask for custom vinyl stencils. If they cannot do them, they can probably tell you who can.
Place a square around the area you plan on etching. Next get a razor or exacto knife and cut the other shapes needed out of electrical tape. This takes patience and concentration. Lay them down accordingly onto the blade. Make sure you press the tape down really well because if anything gets past it, it will mark areas you don't want to.
Paint down nail polish were you plan on etching. Make a electric tape border once it is dry. Take your pencil, pin, or any other small device and carve away the polish where you want to etch. This takes time because you need to make sure all the little pieces of polish are out of the grooves you create.
Step 4: Almost There
Now you can set up your little etching device.
Take one alligator clip and attach one end to the positive part on the battery (my red clip). Take the other end and put it on an empty part of the blade. Be careful where you place it on the blade, mine slipped off a few times.
Take the other alligator clip and attach one end to the negative part on the battery (my green clip). Dip a Q-tip in the salt water. I find that you need to get it wet enough that it isn't 'just moist' but it isn't dripping wet. Attach the remaining end of the alligator clip to the Q- tip head. You don't need it on the very end, but it needs to be touching the water.
Step 5: Etching
Now we can etch!
Place the Q-tip head onto the blade where you want to etch. Move slowly while passing over your entire design. I like to rock it back and forth while I move. You will notice a little puff of white smoke and a pungent odor as you etch, do not breath this in! Use in a well ventilated area. This is also a sign that it is working. Look at your Q-tip. It should be changing colors, from blue-green to a brown. This is the metal that you are removing. When the Q-tip gets really dirty looking take the clip off, dip the other end in water, add clip, and continue. The more passes you make with new Q-tips, the darker and deeper the etch will be. I use about 3-4 Q-tips.
When you feel like it is ready, remove the clips and walk over to a sink. Wash all the water off (while pointing the blade tip down) and remove the tape then dry. If your etch is still there good! You did it! Congrats! Hope you liked the instructable!