Can I etch copper?

[forgetaboudit]

Ive got a newly installed sight glass, but now I want to slide a piece of copper piping over it and cut a 3/8" slit out of it the long way to be able to see the plasic pipe for the sight glass. I want to try etching volume markings in the copper the way people do to stainless with a qtip, saltwater solution, and a 9v battery.
Before I go out and buy a chunk of pipe, will it even work on copper?

 

[mj1angier]

https://www.instructables.com/id/Electric-copper-etching/

 

[forgetaboudit]

https://www.instructables.com/id/Electric-copper-etching/

This seems pretty advanced for what I want to do

 

[AkTom]

If nothing else... you can scratch lines till you can get it etched.

 

[AnthonyTD]

Electronic pcbs are all etched copper. Just google pcb etching and you will find plenty of different methods.

Mutric acid (pool acid) and hydrogen peroxide will be the chemicals used you need.