Asbestos question

[Mick Bailey]

I have a Traynor in for repair where one of the main Mallory filter caps has been replaced with a much older dual can-type. It had failed and completely ejected its guts into the amp. The owner did a superficial clean up and left it untouched for a good while. Now its with me for restoration, though is quite badly corroded. My main concern is that the inside is strewn with fibrous floss and I wondered if this contained asbestos. I assume its just paper, but I took a good sized sample in tweezers and attempted to burn it, but it won't combust. After about a minute of continuous flame it will eventually blacken, but doesn't turn to ash.

Now, it could be that the dried electrolyte is flame-retardant, or it could be of concern. Does anyone know if asbestos ever found its way into capacitors?

There's a patent number 503370 on the can but I was unable to reference this.

Edit; I just found a number of references to asbestos being woven into the paper to improve performance - e.g.

"United States Patent US. Cl. 317-259 2 Claims ABSTRACT OF THE DISCLOSURE 'A dielectric capacitor comprising electrodes with impregnated paper therebetween, said paper containing cellulosic papermaking fibers and amphibolic asbestos selected from among anthophyllite, tremolite, and amosite, as an adsorbent scavanger for ionic constituents in the impregnant. Asbestos may also be part of the paper wrapper for the wound capacitor body."

[drewl]

I treat everything I find in amps as toxic material.

Between God knows what chemicals, various forms of rodent feces and insect remains I see in old amps, I use caution.

[Enzo]

It is unlikely to be asbestos.

[Justin Thomas]

What Enzo said, but also what Drewl said. I've definitely run across "mystery guts" that proved to be skin or eye irritants, so I'm a little more careful now. Especially with cracked tubes - that cathode coating can be wicked.

The only place I've seen asbestos in amps is on back panels of high-powered amps. I had a Peavey Deuce that I think had it.

Justin

[Mick Bailey]

I did another check and the material doesn't burn. The charred appearance brushes off and the fibre remains white and intact. I do know that asbestos was used as a filler material in in the moulded casings of many capacitors, though the material is bound with resin and not free. 70s Peavey's had an asbestos-looking material on the back panels and when I repeatedly asked Peavey if this is asbestos they never replied, despite every other question over the years being answered promptly. I assume it is asbestos fibre board.

What I've done is bagged the amp and suggested the owner gets the material certified either way - It costs just £25 to get this done.

Interestingly, capacitor manufacture gets a specific mention here;
https://malignantmesotheliomalawyers...elioma-lawyer/

[Mick Bailey]

The asbestos test result came back today. Fibres had been examined using stereo microscopy, polarized microscopy and dispersion staining. No asbestos found.

[HaroldBrooks]

The asbestos test result came back today. Fibres had been examined using stereo microscopy, polarized microscopy and dispersion staining. No asbestos found.

My Uncle worked loading coal as a kid, packed powdered asbestos around oil burners for 40 years, smoked Cigars for 50 years, and still lived to be 88 years old without any lung issues at all.

Not typical I believe, but if you are only exposed to one bad thing for a very short period in a very small amount, my guess is it wouldn't amount to much.

Still it pays to be just a bit cautious in any event !

The guys that did themselves in are the ones who worked in demolitions of asbestos pipe casings, and ship builders who used to spray the stuff onto everything, or people who worked in unvenalated factories with the stuff daily for several years. Many of them tragically died young.

I feel (no science here, only feelings) you have to have a collection of things go wrong and have the necessary risk factors built into our genes, then you are in danger. Problem is, no one keeps an accurate record of all the bad things they were exposed to generally or knows enough about their family tree.

I remember seeing a medical report that smoking can lead to mouth and lip cancer, and whiskey straight up also, but drinking straight whiskey consistanly while smoking every day and the risk are many times more than the independent ones combined. There is a synergy of bad things the brings on a near certainty for sickness.

Again, I am no doctor, just posting an opinion, so take my words with a grain of salt...( but watch it, too much salt is no good for you...)

[Mick Bailey]

I worked with asbestos in my first job. Squares of material were cut by an earlier shift and I had to cut them to a rough circle, mount each one in a lathe and machine out the centre. Then remount it on the external jaws and turn the outside to a finished diameter. It then went into a fixture to drill holes. No mask and I looked like I'd been in a feather pillow fight at the end of the day. Later on when we got our first house it had old 60s Artex on the walls, painted over with gloss paint. I cut teeth into an old plane blade and planed grooves in the walls of 8 large rooms, soaked them with warm water and scraped it off. When it had dried, sanded the rest away. I later became aware that much of this was asbestos based. But not until I'd renovated another two houses that had the same stuff covering the walls.

So I'm now pretty cautious about anything that may contain asbestos. It could be that my luck runs out.