Leach Relay

[darshevo]

I got this in a bin full of parts that came from some microwave equipment (radio/television not dinner :lol: ) And clue as to the metal making up the contact points? The 2 center pieces and the lower look like lead, but are not soft. The upper contact point appears to be something completely different. They measure about 1/4" across and about a 1/16" tall. There is no corrosion or electrical wear to speak of on any of them. The coil is marked 24 volts DC, 250 ohm.

I haven't really dug into the bin this came in in to see if there are more like it. Wondering what the contact points are likely made out of as well as if its worth my time to attempt to remove them (assuming they are some form of PM) or if I should just toss it in the breakage bin and move on to the next deal





-Lance

 

[Sodbuster]

darshevo:

How many of these do you have ?
You could send um my way and I could break um down for ya.
Just hate to see stuff like this go to breakage.

The upper point looks like your typical silver alloyed points. The black ones look like they mite be either overheated silver points or they could be a tungsten alloy of some kind.
Try and clip one of the black ones in half and see if it shatters like tungsten.

I can't see in the picture if the bottom black point is installed to the buss like the top shinny point is, or if it is spotted to the buss. If it is spotted to the buss it is likely to be the tungsten alloy.

The tungsten points will usually have an extremely flat contact surface unlike the upper point in the picture that has more of a dome to the contact surface.

Ray

 

[Harold_V]

I'm with you, Ray. They look like tungsten to me.

Harold

 

[darshevo]

Both the upper and the lower contact points are attached to a post that goes through the buss and has a swedge type fit. If it helps any I was messing around with it some more last night and found that the dark grey pad are actually quite shiny with a small amount of scraping with a knife.

I took my line pliers to one of the contact sets and I was able to shear a piece off. it doesn't seem to be brittle at all.

I have been looking for a good excuse to attempt the nitric recipe from the forum. Would the pads react the same as say sterling if they are indeed a silver alloy?

I am unsure if there are more in the bin or not at the moment. This was laying on top and initially I grabbed it off to check and see if it might have any collector value (it doesn't). Then when I was inspecting it closer I noticed the contact pads.


-Lance

 

[texan]

http://www.leachintl2.com/

That unit does not show in their present catalog but some one at the company may have the specs on it.

texan

 

[qst42know]

That's certainly an old one and has seen little use.

Does it work?

Have you checked collector value?

 

[Sodbuster]

Not likely to be tungsten if they are swedged onto the buss tab like the top ones. Tungsten would tend to fracture or split at the swedge.

So that's good, these should have a good silver content if you didn't see copper on the inside of the one you clipped in half. Some points are copper with a silver crown and then the entire point is clad with silver giving it a uniform appearance.

It could be that the upper circuit had never been used for the life of the relay, wile the lower circuit had been overloaded or overheated at some point causing the discoloration.

That bottom black one still looks an awfully lot like a tungsten point to me, with that flat surface, wile all the others seem to have a domed surface.
I guess you would find out real quick if you stuck it in some 50/50 nitric.

Ray