Cadmium, simple test for?

[Sub MandrelParticipant @submandrel]

There’s more than a minute amount in teh easyflo solders.

 

I have read about taht fatality, and if I recall correctly the problem was poor ventilation combined with use of an oxy-acetylene torch – result too hot so the cadmium boils out of the solder…

 

Neil

[Ian S CParticipant @iansc]

A few years ago a bloke in NZ died after welding galvanised iron in the freezer of a fishing boat at sea, the effect of zinc in an unventilated space. Ian S C

[KWILParticipant @kwil]

Neil makes it quite clear, it is the lack of proper ventilation you should worry about.

 

I have used cadmium included silversolder for the last 58 years and also been around oxy-acetylene / oxy-propane and silver solder part of that time. Still here!!

Edited By KWIL on 18/12/2011 11:01:46

[Paul FallertParticipant @paulfallert28101]

Cadmium ID – an materials engineer told me today that cadmium platers can give the finish any color. He worked his for a multi-national switchgear company and was in the testing department. Visual will not be reliable.

 

On the other hand, I tried the fingernail test on some samples of nuts and bolts. I pressed a thumbnail as hard as i could into the surface and examined the results.

 

Nickel – no mark

Chrome – no mark

zinc – no mark

 

Cadmium – left a definite (but not deep) scratch that would not wipe off.

 

For comparison, I have a piece of world famous Stephenson-Blake letterpress foundry type metal (alloy of lead, tin, antimony). No mark.

 

Is that indicative?

 

Paul

[John HaineParticipant @johnhaine32865]

Long ago in A-level chemistry learning qualitative analysis the test for cadmium was to look at the colour of a bunsen flame in which one held a little loop of wire with a drop of the salt on it. You could dissolve a bit of an unknown metal in some dilute acid. Bunsen had to be adjusted for a colourless flame first. IIRC cadmium gives a scarlet red flame. Our enlightened teacher encouraged us to set fire to small pieces of the metal on a gauze over a bunsen – lovely colour intense red flame. I don’t think many of my chemistry classmates succumbed to anything nasty.

 

Anyway there’s your answer. Rub a little acid (vinegar would probably do the trick) on the plating, then use the end of a bit of clean copper wire to pick up a little of the liquid and see if you get a red flame (before the copper gets too hot and gives you a green one).

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