You need:
- a car battery charger
- q-tips
- a saturated salt solution
- an metal object to engrave
- masking tape (plain adhesive tape works)
Steps:
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Cover the parts of the metal object you don’t want to engrave with tape (do one side at a time, because you need a place to make electrical contact).
Mix vinegar and salt.
Clamp the + clamp onto the metal object.
Put a q-tip in the – clamp, so it touches the cotton
Dip the q-tip in the salt solution (do this frequently)
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Rub the q-tip on the exposed metal, it will start to bubble and foam and get dirty. Don’t touch the metal directly with the clamp, you don’t want sparks
Change the q-tip when it’s become too dirty. Wipe the metal and the – clamp from time to time.
Ventilate your room because the chemical reaction stinks.
Work evenly along your surface to engrave, continue until it seems engraved deeply enough.
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Remove tape and admire.
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You can re-apply tape on small sections and engrave it some more if needed.
Some other thing I did with this process:
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