Cadmium solder - Page 1
Forum section: electronics / beginners

author: Antonio90
author_rank: Frequent Contributor
timestamp: October 11, 2024, 03:31:03 pm
content: Hello.Sorry if this is not the correct place for asking these questions.Feel free to move it to wherever it should be.I saw a Marconi Type 6460/1 RF power meter for a very low price (without the power sensor, so mostly useless), and grabbed it out of curiosity and for parts.Opening it, I saw a small bottle tied with a plastic band and screws, which happens to have a roll of cadmium solder in it. It also states something in the line of using it to repair certain connections marked red.I don't have any need of working with cadmium solder, and don't intend to use it.The question is, how dangerous is it? Can I safely take parts from it? Mainly transistors, connectors, maybe the transformer if it works, etc.Or should I just take it to the hazardous materials part of the landfill?

author: TimFox
author_rank: Super Contributor
timestamp: October 11, 2024, 04:28:45 pm
content: Cadmium solder was used in the past to minimize thermal EMF against copper for sensitive DC circuits.It was also used in jewelry for soldering gold due to its color.There really isn't a good replacement for it, but it is hazardous and not readily available.A pro-cadmium website:https://www.cadmium.org/

author: Antonio90
author_rank: Frequent Contributor
timestamp: October 11, 2024, 04:41:41 pm
content: Quote from: TimFox on October 11, 2024, 04:28:45 pmThanks for the answer. I have been investigating a bit about cadmium and it is indeed quite interesting. Cadmium solder is also widely used in superconductor physics experiments. Seems to be very good at wetting aluminium and joining dissimilar metals too.Still, not sure about whether soldering and desoldering it is a health hazard or not too much. Or whether it is safe to touch. I guess, like BeCu and CuTe, it's mostly safe as long as not molten or machined in any way.The sensor is thermocouple based AFAIK. Still quite expensive, and I really have no need for it.

author: TimFox
author_rank: Super Contributor
timestamp: October 11, 2024, 05:00:21 pm
content: Beryllium (as in pure Be, BeO ceramic, and BeCu alloy) is dangerous when inhaled, especially when powder is formed by grinding or other machining.One of my professors at University of Chicago was a young member of the Manhattan Project, and contracted berylliosis (also known as chronic beryllium disease) while polishing beryllium windows for particle detectors.He lost a lung to the disease, but lived until 1988, when his cause of death was lung failure due to berylliosis.However, soldering with cadmium alloys is hazardous due to the high temperatures involved: ventilation and personal protection are mandatory.

author: Antonio90
author_rank: Frequent Contributor
timestamp: October 11, 2024, 05:18:29 pm
content: Quote from: TimFox on October 11, 2024, 05:00:21 pmI see, thanks. Not happening anytime soon then, no need to endanger my family and myself for a hobby.

author: BrokenYugo
author_rank: Super Contributor
timestamp: October 11, 2024, 06:32:27 pm
content: Chassis on something that old may be cad plated as well, same with a lot of older premium hardware.If lead length permits you could simply clip out parts of interest and leave the solder be.

author: coppercone2
author_rank: Super Contributor
timestamp: October 11, 2024, 08:44:27 pm
content: I think its basically inert unless your constantly servicing or assembling equipment with it.And it would be 100% controlled by a dust mask and gloves, with a dedicated soldering iron tip (keep it in a film canister)How many NiCad batteries have leaked on people over the years? Their hardly uber reliable. Banned to save the garbage dumps and to protect people that have NO idea that the residues is hazardous.I think its one of those things you don't want to use structurally, or to have people use without knowing the risks, or have it proliferate in manufacturing, but there is ALOT of cadmium out there already.I think what gets people with this material is if they end up servicing objects that repeatedly expose them to it, and they don't take controls. Like a repair tech getting some particular piece of equipment frequently.Cadmium plated stuff is like really common. And I bet lead paint is worse then cadmium platingHowever, dealing with cadmium plating is a hazardous task, much more so then soldering. That is something that you need to use alot of controls to deal with.Making a few solder joints will probobly get you zilch exposure (with disposable gloves), but sanding down a cadmium plated chassis is dangerous

author: Zero999
author_rank: Super Contributor
timestamp: October 11, 2024, 09:40:47 pm
content: It should be safe enough in its solid state, as long as you don't chew it, if it oxidises and produces dust which can be inhaled.Normally soldering doesn't produce enough vapour, but I don't know about cadmium. According to Wikipedia, its melting point is 321°C, which is closer to its boiling point of 767°C, than lead's of 1749°C, so it will produce more toxic vapour. My advice is don't solder with it, without a face mask and fume extraction.If you don't want to solder with it, then just leave it where it is and don't touch it. There's no need to get rid of it.

author: Antonio90
author_rank: Frequent Contributor
timestamp: October 11, 2024, 10:25:58 pm
content: Quote from: Zero999 on October 11, 2024, 09:40:47 pmI didn't intend to get rid of the solder. It is in a bottle, very well closed, and can be taken out and stored safely. My concern is with actual solder joints made with it and freely exposed, possibly desoldering them, and, maybe, rusted plating. Although I don't really know what to look for, wrt possible cadmium plating.I will have a closer look at it in a well ventilated area once it stops raining, with disposable gloves, and have a read of the manual. It might very well say which joints are the ones with cadmium in them.

author: TimFox
author_rank: Super Contributor
timestamp: October 11, 2024, 10:50:08 pm
content: Roughly, you can distinguish solid cadmium solder from tin-lead solder by the color, which is yellower for Cd-bearing alloys.