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Light torch. Take the pick and hold it like a pencil or paintbrush. If using a paper clip, bend it out all the way to a straight shape. Quickly take a pick out of flame and place on the ring in the desired location and start engraving your name or whatever you wish to write. The hot pick will easily melt through the PVC, so don't push too hard. When it does get hard to push, this means it is cooling down. You need to put the tip of the pick back into the flame until it glows red hot again and continue engraving. It will smell bad, but it is harmless. This step may take a while This will stop the possible deformation of the ring due to the heat from the pick.
If you want to engrave your ring, take the propane/mapp gas torch and metal pick/ paper clip. Set torch on a low setting. 9 Place tip of pick/ paper clip into the blue part of the flame until it glows red. Once done engraving, place ring in cool water for 10-20 seconds.