lehighline posted:Unfortunately, zinc pest is a lot more common than most people think. The problem is related to specific batches of zinc alloy that get contaminated with lead. Most US and European white metal casters figured this out back in the 1930s. By 1950, much of the problem had disappeared. It returned when manufacturing went overseas. At this point, I think the small mom and pop Chinese foundries are the most likely source of the problem, as they scrounge whatever they can find and throw it in the pot. There is no QC on the melt, so who knows what is in it. Too much lead, and the time bomb starts ticking. It's not a matter of if, but when. And the issue is not specific to a particular brand. MTH, Lionel, Weaver, Atlas, K-Line, they all have it to some degree or another. Until the brands get together and tell the foundries they need to produce quality melt, and show proof that they are in fact producing quality melt, the problem will continue. Unfortunately, the "proof" part costs money and requires expertise which may be unavailable to the foundries.
Chris
LVHR
"using 99.99% pure zinc metal to avoid the problem, and articles made after 1960 are usually considered free of the risk of zinc pest since the use of purer materials and more controlled manufacturing conditions make zinc pest degradation unlikely."
Chris is absolutely correct here, this disappeared in the 1960s only to reappear in an unregulated manufacturing environment overseas.
steve
