Wells hotplate corrosion alert.

[guninhand]

I got a used Wells model H33 hotplate off eBay 4 or 5 years ago. It was working great with usually 30 or so pounds of lead in a melt, then recently no heat, even though the amber light indicated current was on. I had never opened the inside since I got it and when I did was surprised to find severe corrosion on the heating element and grounding leads. The first picture shows corrosion on the ground wire and the second shows the cleaned up heating element leads with lots of pitting. It's working again so you might want to check out yours so you don't have to drill out seized screws, and apply an appropriate grease or other preventive measure.

[OS OK]

Any connection that has high heat will do this, it's just that we don't inspect these connections until they have quit working. It's a long slow process and a sure thing.

[EDG]

Consumer hardware is often not designed using materials that are really corrosion resistant.

Military, medical and semi-conductor equipment engineers will use often use tinned or plated bus bars to prevent corrosion. In some cases even gold plating is used.

[Walter Laich]

curious...
what kind of grease would stand up to that kind of heat?