Help needed cutting up old magnetron with torch
Ian W. Douglas
I have the magnetron from an old Amana Radarange which I took apart
a while ago, and since the oven was so old (presumably containing a
lot of out-of-production parts) I was thinking of cutting
the magnetron apart with a cutting torch, since this would be less
labour intensive than using a hacksaw. Also I have another non
functional microwave oven in addition to one which does work, so the
magnetron is even more expendable. The reasons I wish to do this
are (a) to see the resonant cavity inside this device, (b) recover
the soft iron magnets, and possibly (c) look at the filament area
and electrodes inside the cavity area. All this would enable me to
gain additional understanding of how a magnetron works.
Before I light up the torch, are there any potential hazards to doing
this which I should worry about, apart from the usual need for
precautions when using a cutting torch? Are the cavity and filament areas
under vacuum, and if they are therefore sealed, then should I worry about the
possibility of an explosion? Are there potentially toxic materials inside
this device which a torch would turn into harmful vapours?
The magnetron in question is a Hitachi 2M170, part #C87617-2TH (yes, Amana
ovens did have Japanese magnetrons in them).
Thanks in advance for any help,
Ian Douglas
Sam Goldwasser
is an unusual design. They should be outside the vacuum bottle.
I used a hand grinder to get inside the typical magnetron found in modern
ovens. See:
http://repairfaq.cis.upenn.edu/sam/maganode.gif
This is the cross section of the resonant cavity portion of the tube.
BTW, don't expect it to look like the photos/diagrams in your WW2 radar text!
--- sam | Sci.Electronics.Repair FAQ Home Page: http://www.repairfaq.org/
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Lord Garth
another piece of history in the Mostek IC that ran the touch
panel. It was from the Industrial Products division under the
Telecom department ... I might have the specs on that chip.
"Ian W. Douglas" <idou...@calcna.ab.ca> wrote in message
news:Pine.A41.4.05.100121...@srv1.calcna.ab.ca...
Jerry G.
loose their magnetism from heat.
There is a high vacuum in this tube, and chance of implosion rather
than explosion. The implosion can actualy be more dangerious.
Everything will want to cave in at high speed, and then excelerate
in the on going direction to the opposite sides of entry with great
velocity. I have had the experience of seen high vacuum tubes
implode, and this is a very hazardous conditon.
I have broken CRTs by placing them in a double duty heavy thick
cardboard shipping box that has a hole in it. I then run in a long
heavy steel pipe through to the neck of the tube. This is even
considered dangerious!
--
Jerry Greenberg GLG Technologies GLG
==============================================
WebPage http://www.zoom-one.com
Electronics http://www.zoom-one.com/electron.htm
Instruments http://www.zoom-one.com/glgtech.htm
==============================================
"Ian W. Douglas" <idou...@calcna.ab.ca> wrote in message
news:Pine.A41.4.05.100121...@srv1.calcna.ab.ca...
David M. Brodbeck
> There is a high vacuum in this tube, and chance of implosion rather
> than explosion. The implosion can actualy be more dangerious.
> Everything will want to cave in at high speed, and then excelerate
> in the on going direction to the opposite sides of entry with great
> velocity. I have had the experience of seen high vacuum tubes
> implode, and this is a very hazardous conditon.
--> Magnetrons are metal, not glass though, right? So I'd think instead of
a catastrophic implosion, you'd just get a brief bit of hissing when your
cutting tool first broke through.
---------------------------------------------------------------------------
David Brodbeck, N8SRE dmbr...@mtu.edu
finger gu...@cyberspace.org for my public key block.
"He's so dull, he ordered Irish coffee during a layover at Shannon
Airport with the instruction, 'Hold the whiskey, and make it decaf.'"
-- Margaret Carlson, writing about Warren Christopher.
Lord Garth
It in the center on the socket. It's safe too.
"Jerry G." <jerr...@hotmail.com> wrote in message
news:7ogZ5.26826$H52.5...@news.total.net...
kc8adu
berylium oxide and it is bad stuff.
"Ian W. Douglas" <idou...@calcna.ab.ca> wrote in message
news:Pine.A41.4.05.100121...@srv1.calcna.ab.ca...
>
>
Andre de Guerin
<idou...@calcna.ab.ca> wrote:
>
>
>I have the magnetron from an old Amana Radarange which I took apart
>a while ago, and since the oven was so old (presumably containing a
>lot of out-of-production parts) I was thinking of cutting
>the magnetron apart with a cutting torch, since this would be less
>labour intensive than using a hacksaw. Also I have another non
>functional microwave oven in addition to one which does work, so the
>magnetron is even more expendable. The reasons I wish to do this
>are (a) to see the resonant cavity inside this device, (b) recover
>the soft iron magnets, and possibly (c) look at the filament area
>and electrodes inside the cavity area. All this would enable me to
>gain additional understanding of how a magnetron works.
>
>Before I light up the torch, are there any potential hazards to doing
>this which I should worry about, apart from the usual need for
>precautions when using a cutting torch? Are the cavity and filament areas
>under vacuum, and if they are therefore sealed, then should I worry about the
>possibility of an explosion? Are there potentially toxic materials inside
>this device which a torch would turn into harmful vapours?
As it is such an old magnetron, I'd be concerned about beryllium oxide
ceramic (read-similar in danger to asbestos when fragmented), also
thorium dioxide on the filament . (radioactive, toxic)
Charles Godard
you buy it.
--
ChasG
Godard's TV & Computer Service
Delhi, La --- since 1978
http://qualitytuner.hypermart.net
"Andre de Guerin" <mand...@gtonline.net> wrote in message
news:3a353bf...@news.virgin.net...
Jorgen Lund-Nielsen
Andre de Guerin schrieb:
>
> >possibility of an explosion? Are there potentially toxic materials inside
> >this device which a torch would turn into harmful vapours?
>
> As it is such an old magnetron, I'd be concerned about beryllium oxide
> ceramic (read-similar in danger to asbestos when fragmented)
!!!!! Beryllium Oxide is *much* more carciogenic than Asbestos !!!!!!!
Don Bruder
<jerr...@hotmail.com> wrote:
: I have broken CRTs by placing them in a double duty heavy thick
: cardboard shipping box that has a hole in it. I then run in a long
: heavy steel pipe through to the neck of the tube. This is even
: considered dangerious!
Safest, easiest method of de-vacuuming (re-pressurizing?) TV CRTs I've
ever found is to look for the little glass "tit" that's used to pump 'em
down during manufacturing. It's almost always centered amongst the
connecting pins. Take a pair of pliers and crush it or snap it off.
After using that method on hundreds of CRTs (used to work as a
counter-droid/cleanup man at a TV repair shop, and the only way the
garbage collectors would take a dead TV set or old CRT was if the CRT
was physically broken or could be shown to be non-implodable) I can say
it's quick, safe, and effective. Never had a single one of them do
anything more violent than whistle.
<CLICK>
<FSWEEEEEEEeeeeeeeeee>
<cart to curb on Tuesday morning>
--
--
Don Bruder - Dak...@primenet.com
Horseman by day, 'net-freak by night. What a contrast, eh?
Don Bruder
<dmbr...@mtu.edu> wrote:
: In sci.electronics.repair Jerry G. <jerr...@hotmail.com> wrote:
: > There is a high vacuum in this tube, and chance of implosion rather
: > than explosion. The implosion can actualy be more dangerious.
: > Everything will want to cave in at high speed, and then excelerate
: > in the on going direction to the opposite sides of entry with great
: > velocity. I have had the experience of seen high vacuum tubes
: > implode, and this is a very hazardous conditon.
:
: --> Magnetrons are metal, not glass though, right? So I'd think instead
: of
: a catastrophic implosion, you'd just get a brief bit of hissing when your
: cutting tool first broke through.
Which is exactly what happened when I performed the exercise using a
hacksaw about 2 years back.
David M. Brodbeck
> Try using a Dremel tool. You'll find 1001 other uses for the Dremel after
> you buy it.
--> Wear safety goggles, though. The Dremel cut-off discs are brittle and
I've heard horror stories.
Rich Grise
the magnetron, since it's probably made of copper. You'll
end up with a huge mess and no usable magnets. With an
oven magnetron, I don't think implosion is anything to
worry about - if you've disassembled it this far, you've
probably already broken the vacuum anyway. I've found that
a Dremel-type tool with an abrasive disk and a vise-grip
style locking pliers can make pretty short work of a
magnetron!
Good Luck!
Rich
Lizard Blizzard
"Ian W. Douglas" wrote:
>
> I have the magnetron from an old Amana Radarange which I took apart
> a while ago, and since the oven was so old (presumably containing a
> lot of out-of-production parts) I was thinking of cutting
> the magnetron apart with a cutting torch, since this would be less
> labour intensive than using a hacksaw. [snip]
> Are there potentially toxic materials inside
> this device which a torch would turn into harmful vapours?
The magnetron and just about any tube that uses a filament has a
filament or cathode that can have a coating of oxide that may contain
barium or other possible toxic materials. If the cathode is at room
temperature, there is little risk of toxicity, but with a cutting torch
it's almost certain that thee will be gases with nasties in them. Do
all cutting outdoors and don't breathe the fumes.
Jim Adney
>I have the magnetron from an old Amana Radarange which I took apart
>a while ago, and since the oven was so old (presumably containing a
>lot of out-of-production parts) I was thinking of cutting
>the magnetron apart with a cutting torch, since this would be less
>labour intensive than using a hacksaw.
All the magnetrons I'm familiar with (not oven magnetrons) have copper
bodies. Copper doesn't cut well with a cutting torch, so if this is
what you have you won't learn anything this way; you'll just end up
with a pile of copper slag.
Try the hacksaw or a band saw.
-
-----------------------------------------------
Jim Adney jad...@vwtype3.org
Madison,Wisconsin USA
-----------------------------------------------
Sam Goldwasser
2 minutes on a power grinder, maybe 10 minutes on a hand grinder.
--- sam | Sci.Electronics.Repair FAQ Home Page: http://www.repairfaq.org/
Repair | Main Table of Contents: http://www.repairfaq.org/REPAIR/
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| Mirror Site Info: http://www.repairfaq.org/REPAIR/F_mirror.html
Koen Van Vlaenderen
My dad was using it at full speed (with safety goggles) and the disc broke and a
sharp piece ended up sticking in the goggle (plastic goggle) !
always use goggles and watch your eyes!
Andre de Guerin
<jorgen.lu...@desy.de> wrote:
>
>
>Andre de Guerin schrieb:
>>
>
>> >possibility of an explosion? Are there potentially toxic materials inside
>> >this device which a torch would turn into harmful vapours?
>>
>> As it is such an old magnetron, I'd be concerned about beryllium oxide
>> ceramic (read-similar in danger to asbestos when fragmented)
>
>
>!!!!! Beryllium Oxide is *much* more carciogenic than Asbestos !!!!!!!
How dangerous .. ?
I was under the impression that they'd stopped using it except in
things like VHF amplifier modules .
Jim_Thompson
Only Beryllium Oxide DUST is dangerous if inhaled...you can eat the
stuff without harm.
We used to saw the stuff under oil to make high thermal conductivity
substrates for hybrid circuits (~1970). Then we cleaned it with TCE
;-)
(If replying by E-mail please observe method of anti-spam.)
...Jim Thompson
--
| James E.Thompson, P.E. | mens |
| Analog Innovations, Inc. | et |
| Analog/Mixed-Signal ASIC's and Discrete Systems | manus |
| Phoenix, Arizona Voice:(480)460-2350 | |
| Jim-T@analog_innovations.com Fax:(480)460-2142 | Brass Rat |
| http://www.analog-innovations.com | 1962 |
For proper E-mail replys SWAP "-" and "_".
Lord Garth
>
> How dangerous .. ?
>
> I was under the impression that they'd stopped using it except in
> things like VHF amplifier modules .
Go back in the thread to the post I made and there is a link that will take
you to a US government document regarding beryllium oxides effects on
the human body.
Andre de Guerin
wrote:
What post .. ???!
Its not there .
>
>
>
>
>
Lord Garth
here is a repost:
----------------------------------------------------------------------------
--
It's not always purple. Here is an extract and the link:
http://tis-hq.eh.doe.gov/web/oeaf/oe_weekly/oe_weekly_98/oe98-08.html
The Environmental Protection Agency classifies beryllium oxide as a special
health hazard substance because it is a carcinogen. Beryllium oxide is a
white, odorless powder that is used in ceramics, glass, electron tubes,
electronic components, nuclear fuels, and nuclear moderators. Beryllium
oxide inhalation can lead to chronic beryllium disease. According to the
Environmental Protection Agency, chronic beryllium disease is irreversible
and can produce the following effects.
High exposures of beryllium oxide usually result in severe bronchitis or
pneumonia, within 1 to 2 days after exposure, accompanied by fever, cough,
and shortness of breath.
High exposures of beryllium oxide can result in death.
High or repeated low exposures of beryllium oxide can scar the lungs and
other organs. Fatigue, weight loss, shortness of breath, lung damage, and
heart failure can occur years after the exposure.
Exposure to beryllium oxide can cause an allergic skin rash.
High or repeated beryllium oxide exposures can cause kidney stones.
Additional information about the clinical characterization of chronic
beryllium disease can be found in the Defense Programs Beryllium Good
Practice Guide and in DOE G 441.1-7, Implementation Guide for use with DOE N
440.1, Interim Chronic Beryllium Disease Prevention Program
"Joe Bloe" <Joe...@thebarattheendoftheuniverse.org> wrote in message
news:enlb3tk1ofhk23ioc...@4ax.com...
> On Tue, 12 Dec 2000 00:21:09 -0800, "kc8adu" <nos...@spam.sucks>
> Articulated:
>
> >whatever you do do not break the ceramic and inhale the dust.
> >berylium oxide and it is bad stuff.
>
> Try beryllium oxide would be nearly instantly deadly as in DO NOT
> EVEN TOUCH IT! If you cut you finger with a beryllium ceramic
> material you can kiss your ass goodby. This is no shit people!
>
> Breathe hell... don't even look at the shit. I can't emphasize this
> enough! Purple is bad.
>
>
> TopQuark...
----------------------------------------------------------------------------
----
"Andre de Guerin" <mand...@gtonline.net> wrote in message
news:3a3bcacc...@news.virgin.net...
Jim Witte
> you can eat the stuff without harm.
I wouldn't...
Jim
Andre de Guerin
wrote:
>Your view is probably set to only display unread messages....
BTW is this stuff used in heatsink compound ?
Brad Thompson
Andre de Guerin wrote:
> >----------------------------------------------------------------------------
> >--
> >It's not always purple. Here is an extract and the link:
> >http://tis-hq.eh.doe.gov/web/oeaf/oe_weekly/oe_weekly_98/oe98-08.html
> >
> >
> >The Environmental Protection Agency classifies beryllium oxide as a special
> >health hazard substance because it is a carcinogen.
> <snip>
>
>
> BTW is this stuff used in heatsink compound ?
Hello--
No-- the white substance in heat-sink compound is usually zinc oxide, IIRC.
73--
Brad AA1IP
Clyde Manning
used it. I don't remember if it is the pure metal or an oxide. It is treated as a
hazardous substance when ground up, as the dust is very toxic.
Brad Thompson wrote:
--
邢 唷��
Charles W. Shults III
in packages, the package you order has a pre-made chunk of the ceramic in it
(usually) and that is what you bond to- well, there is a metal coating that
you make the eutectic bond to. But it conducts directly to the beryllium
ceramic which transfers the heat to the case or a heatsink.
Beryllium metal is pretty neat stuff if you ever get your hands on some
(but wash afterwards). It is harder and lighter than aluminum when properly
alloyed and is commonly used in nuclear reactor tubing for cooling or
whatever. I have a small sample that I used for some work a few years ago
and when it is in your palm, it almost feels like there is nothing there.
Cheers!
Chip Shults
SPAM free Email - aic...@gdi.udu.net but remove the .baryon
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