Asbestos in a Zenith C845? Other dangers?

[fltyrap]

Hi Everyone,

I'm new here, and I just acquired a Zenith C845 in great condition. I opened up the cabinet back last night and was surprised at how unbelievably dirty and dusty it was. So, of course I pulled off the knobs, then unbolted and removed the chassis. This is in the apartment I share with my girlfriend.

Well, she had a fit. It smelled, she said. Then she asked, "Is there anything dangerous in there? What about asbestos?"

Good question, and one I can't believe I didn't think of asking myself as someone new to old radios. I looked in the cabinet and didn't see any sheets attached to the cabinet, so sighed a bit of relief. Then, just to be sure, I looked under the chassis.

The C845 has a small square piece of foam, about 1.5"x1.5" and about 3/4" thick, attached to the center of the chassis. on the opposite side (in contact with the cabinet) is a thin metal plate a little larger than the foam. most of the chassis is suspended above the cabinet by this apparatus in the center and a small ledge on either side of the chassis.

So, I got that thing outside and in a plastic bag, and vacuumed up the dust from the cabinet that was on the table I was working on. My questions:

1. Does anyone know if that piece of foam/material contains asbestos? I see that other radios have asbestos sheets, but this was thicker than those-- and it seemed quite pliable. Anybody got a C845 that knows what I'm talking about?

2. If it was asbestos, how dangerous was it to work on this inside (and without a mask)? I mean, I didn't waste time once I saw it, but are these materials in radios generally fairly dangerous, fairly safe without repeated exposure, or somewhere in between?

3. Again, if it was asbestos, would careful removal and washing of the chassis eliminate the risk and make the radio safe for the home, or will it always be dangerous?

4. As somebody new to this, is there anything else I should know about hazardous materials in these suckers? Lead? Fumes from decaying parts?


I'd appreciate any information you have. I now have a disassembled radio on the balcony in a trash bag and a girlfriend who is telling me to throw it out. I would hate to, but I also want to make sure this hobby isn't putting me and my loved ones at risk.

Thanks!

[wa2ise]

AFAIK, asbestos looks like a fiberous crumbly cloth like white stuff, and not foam. You should be okay, and no need to toss that radio.

They used to use asbestos in cigarette filters...:smoke::eek:

[Mark W.]

asbestoes is only dangerous if inhaled and only if it's in a dust like form. I have hard sheets of asbestoes I used to shield things during heat treatment.

The problem comes from inhaling a BUNCH of the fibers which are a fish hook shape and after many many many years they work their way through the lungs to irritate the Plura covering the lungs this then can lead to a type of cancer. But the tiny amount of expose to this you might get cleaning up a Radio or TV wouldn't be a problem.

My dad used to bitch about how they removed the solid asbestoes insulation from schools and such since in that form the asbestoes was pretty much harmless. But once torn all apart and spread all over the place the risk increased greatly.

I have never heard of a single teacher that has had either form of asbestoes caused cancer.

MY dad who worked in the heating and HVAC industry died from Mesothelioma the worst form of asbestoes caused cancer in 2003 his exposure was to bags of powdered asbestoes he mixed with his hands into cement to be smeared onto steam pipes. His exposure ended in about 1964.

The only other person I know of who has contracted a form of asbestoes cancer is the mechanic who worked on the rigs at my dads sheet metal shop his exposure was from 30+ years of doing brake jobs before the industry finally let people know that was a risk.

if you want to know more just google it there's 1/2 million pages of stuff on asbestoes cancer. Much of it alarmest.

I won't go into the major companies involved in asbestoes removal being connected with the mob.




OH and by the way to the best of my limited knowledge asbestoes does not cause you to get sick it either causes one of the two forms of cancer or doesn't.

[radio63]

My opinion is that the risk from asbestos in radio cabinets is insignificant. I have worked on a number of sets that had asbestos sheets in them. I am careful to not disturb the sheets any more than I have to. But I don't sweat them being there at all. If you took the sheets, removed them, crumpled them up and inhaled the dust, that would be dangerous. But to just casually come in contact with them occasionally while servicing an old set is overreacting as far as I'm concerned.

Just be prudent. Don't disturb the asbestos any more than you have to, work in a well ventilated area, wash you hands afterward, and utilize the same caution you would while repairng or restoring the set you are working on. If you are interested in tossing the set, why don't you offer it here on these forums and I'm sure someone would take it off your hands. You are not putting anyone at risk with this hobby unless you want to stick your hand into a live B+ circuit while the power is applied. Then all bets are off. Good luck.

Gilbert

[drh4683]

What you described is not asbestos. That little square is just a black foam pad. Its placed as an isolation/dampener to prevent vibration between the chassis and cabinet, as the C845 is a "hi fi" radio and puts out the sound. the bottom of the chassis has a metal plate cover which can vibrate with excessive bass. This pad prevents that. Actually, Im surprized it still flexible. Most of the time those dry out rock hard.

Generally, asbestos is found in the top of the cabinet on the old radios above the audio output tube. Usually a sheet, very thin, about 1/16" and very fiberous, and whitish/grey in color. Sometimes, it can be corrugated sheet too.

Since it was brought up, I to had an asbestos fear as a kid, but then realized it is not hazardous if its non-friable. So if you dont go crazy shreading it and breathing it, its fine. It is however the best dang insulator ever and is chemically resistant to practically everything. Johns Mannville was a major manufacturer of asbestos related products, if not all of it. They were based in Waukegan, IL as was the processing plant. peices of asbestos wash up on the beachs in Waukegan and Zion and down to the Oak street Beach in Chicago all the time. Supposedly alot of asbestos debris made its way into lake michigan from JM. Thats another story.....

Asbestos is a natural element. Ive heard the ingorant old saying "If its from the Earth, it can't hurt you"........I think not!

[zenithfan1]

They still have signs down there warning of it washing up IIRC. You're right, the non- friable stuff is safe, or at least that is what the taught in the asbestos class I took when I started started working for Dist. 67.

[sprman55]

Hi nothing to worry about the lead.Worked in a small production area ,had EPA come sample the air.They left a thing in the room for 30days.Came and got it,told us there was nothing to worry about as levels were way below the set limit.Decaying parts are of no harm.More than likely you have more harmful stuff under your sink thats used for cleaning.Sprman55

[fltyrap]

Hi Guys,

Thanks for the great and fast info! Your replies have calmed the GF's fears and allowed me to keep the radio. I cleaned it up today (outside, of course), and thought I'd contribute a few photos. A couple are of the foam pad in question (it fell off the chassis, I guess due to old glue), and the others are of the chassis itself (#8C02), which is looking much better after a light cleaning.

[radiotvnut]

I do see one minor detail that needs to be taken care of. That blue finned thing on the front of the chassis is a selenium rectifier. It is used to convert the incoming AC voltage from the wall socket to a DC voltage. These do tend to short and arc. When they do, you'll get a foul odor similar to rotten eggs. I've read that the fumes cam be toxic if you are exposed to them for extended periods. The good news is that this selenium rectifier can be replaced with a modern silicon diode. Something like a 1N4007 or any other diode rated at least 400 PIV @ 1 amp will work. Just unsolder the leads of the original selenium rectifier and remove the rectifier from the chassis. Mount a suitable terminal strip to the chassis to solder the silicon diode to. The only thing you'll need to do when using a silicon diode rectifier is place a resistor in series with the diode. Silicon diodes have less voltage drop than the original selenium rectifiers and failure to use a resistor may result in too much B+ voltage. I'd say a 68 ohm, 5 watt resistor should work. Just connect one end of the resistor to the incoming AC lead. Connect the other end of the resistor to the anode terminal (anode is the end without the band) of the diode. Lastly, connect the cathode terminal (end with the band) of the diode to the remaining lead that goes to the filter capacitor. Make sure your connections are soldered good and see to it that the resistor will not come in contact with wire insulation, etc. These resistors do get a little warm.

Also, if there is a capacitor connected between one side of the AC line and ground, that should be replaced. In this case, it's probably a bumblebee cap. It will be black with colored bands around the case. Those bumblebees were not great to begin with and they are known to blow up, especially when used in line bypass applications. www.justradios.com sells about any kind of capacitor that you'll need for old radio restoration, including special safety caps that are designed to be used safely in line bypass applications. Capacitors are inexpensive and that's why I usually change any line bypass, wax paper, and electrolytic caps that I find in vintage equipment.

Of course, those parts I mentioned could work for another 50 years or they could go belly up tonight. You'd be better to just go ahead and change them just to be on the safe side.

Oh yes, that radio (along with many other radios from this time) has a "hot" chassis. That means that one side of the AC line is connected directly to the chassis. That means there's a 50/50 chance (depending on the AC plug position) that you have 120 VAC on the chassis. This will not pose a threat as long as the radio chassis is inside the cabinet. The ideal way to work on one of these outside of the cabinet is to power the chassis via an isolation transformer. Otherwise, use extreme caution.

I didn't tell you all of this to get your GF on your back. This is stuff that everybody entering the hobby of vintage electronics needs to know in order to get the most out of their equipment and to help insure that they live to an old age.

[Old1625]

The selenium rectifier is indeed of concern, and its switching out can result in much improved performance from the radio. But the rectifier can be excluded without its physical removal. The leads from it go to an existing terminal strip under the chassis, where the leads can be removed, and a diode can be readily installed in the same place without the addition of an extra terminal strip. I just did this to one of my Zenith sets. Use care in observing polarity, unless extreme excitement is your bag.

The isolation transformer as advised is also a prudent step. A lot of those old radios have the on-off switch on the return or neutral side going to the chassis. This means that if the plug is installed one way in the outlet the chassis will bite you when the radio is on--plug it in the other way and the chassis will bite you when it's turned off. It's a no-win situation that existed before the polarized plug prong design. My older sisters used to listen to a Zenith that was missing its knobs. They'd either stand on a pillow before touching the shafts, or they'd use a playing card stuck in the slot of the splined shafts to make changes.

[marty59]

About that A/C plug- hot chassis situation...I'm not sure about your model Zenith, but some have an interlock plug that mounts on the back cover, and it may not be easy to replace/upgrade. Replacing the cord with a polarized type would be a good measure for safety, as well as connecting the on/off switch to the hot side. You can also mark the hot "prong" of the plug so you can insure that you position it properly. Always remember that the neutral of a polarized plug is the large blade, if you change the cord.
Something else I'm in the habit of doing is plugging my old radios into a terminal strip or a plug in switch. For one, no wear and tear on the switch inside your radio, and no need to worry about unplugging it if it's not in use for an extended amount of time, keeping it isolated at all times!

[fltyrap]

Thanks, everyone, for all the excellent information.

I will certainly replace the selenium rectifier. I had no idea they were dangerous when they fail. And as for the hot chassis and other issues, it seems like before I get too into this I need to back up, get some practice circuits and electrical books, and teach myself some basics. First step: acquire a soldering iron.

Thanks again.

[radiotvnut]

Yep, get a soldering iron and a multimeter (even if it's an el cheapo model). These are the two most essential tools for antique radio repair.

[radio63]

Thanks, everyone, for all the excellent information.
It seems like before I get too into this I need to back up, get some practice circuits and electrical books, and teach myself some basics. First step: acquire a soldering iron.

Yes, don't work on any of these sets until you have read some good books and know about the dangers that can be lurking within. If you don't have much electronics experience, I would strongly suggest putting this radio away and learning some basic electronics along with learning to solder and using a multimeter. There are a lot of great older books that cover tube radio circuits. Don't be in a hurry to start on an old radio. Wait until you get a little more knowledge, then you will have more fun and be safer. Good luck!

Gilbert

[fltyrap]

So, I'm recapping this Zenith C845, and I don't know how I didn't notice this before, but there are two fairly stiff sheets of something on the front of the chassis-- in the area of the volume/tone knobs and attached to the tuning dial assembly. I've attached some pictures here so you can see what I'm talking about-- they are dark grey.

Would these sheets contain asbestos? These areas aren't really that close to any tubes, but what would these sheets be for if not thermal insulation?

I might be the hypochondriac in here, but if there is a chance this contains asbestos it will determine if I can work on it indoors, and how safe I'll feel handling it with my face up close in general.

Thanks!

[Bob E.]

Looks like "fish paper" to me...no asbestos. Just thick, high-dielectric paper.

[fltyrap]

Fish paper? Huh. I am a constantly amazed at the breadth of gadgetry to learn in one device.

I wonder why the radio would need electrical insulation between the chassis and the nuts holding the pots in, or between the chassis and the tuner assembly. Was this common practice?