Quite a while ago, I noticed that one of my sprinklers was leaking. It was one of those classic brass ones that us older folk think are high quality. I removed it and took a look, although not such a good look, as I discovered later. The stem leading to the nozzle had corroded away, leading to loss of the gasket surface. This caused the leak. This is a fatal failure, and I put it into a coffee can just in case I ever got a ceramic crucible so I could cast it into something useful.
Fast forward a couple of years, and I noticed that my kitchen sink faucet sprung a leak. It was only about a year old, but it was a generic and probably not meant to be repaired. I decided to strip it for brass. It became obvious that most of the metal in the faucet was not brass. Anything that did not touch flowing water was some kind of zinc alloy, probably zamak. The flange, escutcheon, body, handle were all zamak. They showed corrosion. Only the valve cartridge nut, sealing plate, and the hose fittings were brass. About 5 oz. of brass out of a several pound faucet. I looked at the Internet, and I saw a scrapper video that said that faucets were only worth 0.40 per pound instead of 1.30 per pound for scrap brass, since they were made of less and less brass.
This encouraged me to look back at the failed sprinkler. It was obviously solid brass, but brass doesn't corrode like that. The scrapper video suggested I use a file to tell what is brass and what is zamak. It turns out, under a thin brass plating, most of the sprinkler is zamak. And, both stem and body are quite corroded, to the point of failure. The only brass piece is the nozzle, which must be brass, else it would fail pretty quickly. Doing a web search on this only turned up one interesting hit. A web page said that brass pop-up sprinklers were considered the pinnacle of quality only up to the 1970's after which they were superseded by plastic ones, due to longevity issues. But it didn't tell the reason. So, brass sprinklers may be made of mostly zinc alloy. That may explain a failure I saw in a foundry class using scrap plumbing fittings as stock. Lots of fumes and poor yield. So, make sure you check everything with a file before you throw it into that crucible.
Fast forward a couple of years, and I noticed that my kitchen sink faucet sprung a leak. It was only about a year old, but it was a generic and probably not meant to be repaired. I decided to strip it for brass. It became obvious that most of the metal in the faucet was not brass. Anything that did not touch flowing water was some kind of zinc alloy, probably zamak. The flange, escutcheon, body, handle were all zamak. They showed corrosion. Only the valve cartridge nut, sealing plate, and the hose fittings were brass. About 5 oz. of brass out of a several pound faucet. I looked at the Internet, and I saw a scrapper video that said that faucets were only worth 0.40 per pound instead of 1.30 per pound for scrap brass, since they were made of less and less brass.
This encouraged me to look back at the failed sprinkler. It was obviously solid brass, but brass doesn't corrode like that. The scrapper video suggested I use a file to tell what is brass and what is zamak. It turns out, under a thin brass plating, most of the sprinkler is zamak. And, both stem and body are quite corroded, to the point of failure. The only brass piece is the nozzle, which must be brass, else it would fail pretty quickly. Doing a web search on this only turned up one interesting hit. A web page said that brass pop-up sprinklers were considered the pinnacle of quality only up to the 1970's after which they were superseded by plastic ones, due to longevity issues. But it didn't tell the reason. So, brass sprinklers may be made of mostly zinc alloy. That may explain a failure I saw in a foundry class using scrap plumbing fittings as stock. Lots of fumes and poor yield. So, make sure you check everything with a file before you throw it into that crucible.
