# Silvery Contacts



## shaftsinkerawc (Aug 13, 2011)

Found these cleaning out an old timers garage. Lost a couple of photo's but the contacts were the same, almost as large as a dime and about half again as thick. Have a great day. awc


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## Geo (Aug 13, 2011)

very nice. :mrgreen: looks like new unused contact points.should yield some good silver.


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## floppy (Aug 13, 2011)

What did those contacts come off of?


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## shaftsinkerawc (Aug 13, 2011)

I've got more to clean up in his garage, hope to find some more. They appear to be square D contacts. Here's some other photo's.


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## element47 (Aug 13, 2011)

Nice chunks/shapes of metal. I am skeptical they are silver, but it wouldn't be first time I've been wrong.


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## butcher (Aug 13, 2011)

I bielive them to contain silver, from the pictures they look to be large contact points, if waffle backs can also contain tungsten.

Remember caution if melting, or desoldering these, cadnium fumes are very dangerous, I do not know they contain cadnium but would still take precautions.


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## shaftsinkerawc (Aug 13, 2011)

Thanks for the warnings and replies. Not enough of them yet so they will just go in the look good pile/display case.


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## Harold_V (Aug 13, 2011)

element47 said:


> Nice chunks/shapes of metal. I am skeptical they are silver, but it wouldn't be first time I've been wrong.


They most likely are, even if they're sintered tungsten. That's very typical of the type of construction where silver contacts are commonly used. 

Harold


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## plamenppp (Aug 14, 2011)

Yes, they look nice  I've got kilograms of contacts without the brass or copper. They should be 80-84% silver without the solder included. Be careful when removing them with heat - the contain cadmuim as well. Wear gas mask and do it outside!


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## macfixer01 (Aug 14, 2011)

The copper strips look like they came off some pretty hefty 3 phase contactors or motor starters, and one of them does have a Square D brand logo on it. The big gold-tone chunky pieces look more like they're from some sort of high amperage disconnect or switch box? They appear to each have a hole where they were ganged up on a shaft that rotated to make or break multiple legs at the same time.

macfixer01


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## Geo (Aug 14, 2011)

looks to me like they all came from the same switch, notice the strips have a contact on each end which makes a total of six points and then you have six singles. i think its either a starter switch on a large 3 phase motor which is most likely a 100 hp or greater or a large light switch for the large industrial size Halogen light assembly. in my experience (which is still growing) tungsten contacts are primarily used in breaker switches.


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## macfixer01 (Aug 15, 2011)

Geo said:


> looks to me like they all came from the same switch, notice the strips have a contact on each end which makes a total of six points and then you have six singles. i think its either a starter switch on a large 3 phase motor which is most likely a 100 hp or greater or a large light switch for the large industrial size Halogen light assembly. in my experience (which is still growing) tungsten contacts are primarily used in breaker switches.




True, could be that the chunky pieces are the stationary contacts that the copper strips bridge. The 3 phase contactors I worked with in my refrigeration days were only up to 50 Amps max. This appears to be much higher capacity. Yeah now that I think about it disconnects have knife switch type contacts. Guess I shouldn't make speculations when half asleep.


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