cleaning NOS cutting torch tips

I got a lot of really old but almost entirely unused Airco torch tips today. Many are of a kind I've never seen before. They are *old* new old stock, maybe WWII vintage judging by other items in the same lot. They came in original cardboard tubes which weren't airtight, and they have almost all tarnished. I don't care if a torch tip is shiny or not, but I'm trying to read the number off the things, and polishing 49 tips with Brasso would be tedious. I'm wondering if there isn't some passive method like an overnight soak in citric acid or maybe vinegar and salt that would clean off the tarnish safely.

Anyone?

Grant Erwin Kirkland, Washington

Reply to
Grant Erwin
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I use a buffing wheel and rouge. Less effort than Brasso and they end up nice and shiney. More effort than just soaking but faster. Only removes tarnish off the outside.

Citric acid will also work, but not quite as shiney.

Dan

Reply to
dcaster

Copper will not dissolve in sulfuric acid, but oxides do. You can restore them to almost new looking condition by pickling them in such an acid. Heating the acid will accelerate the cleaning action. (Tried method, not something I read). Don't use metal vessels. Wash well with clean water afterwards. An old auto battery might be a source of acid, assuming you can't find it elsewhere. Protect your eyes and hands. Yeah, I know, you already know that. :-)

Hope this helps-----that's a lot of polishing otherwise.

Harold

Reply to
Harold and Susan Vordos

Perhaps one of the vibrating polishers typically used by reloaders. Not too expensive for the small ones.

Pete C.

Reply to
Pete C.

I decided to try vinegar and salt, having had excellent luck on brass before with it. It worked amazingly well. I made up the solution in a little disposable tupperware and put in a handful of tips and stuck it in the microwave for a minute to let it get hot again, then simply took them out and rinsed them in hot water, wearing rubber gloves. I didn't see any etching or weirdness and they now all look new. Pretty surprising to see them go from dark brown to shiny copper in a minute.

Grant

Harold and Susan Vordos wrote:

Reply to
Grant Erwin

Great choice! Brass in sulfuric would be a bad combination, so not only is your system safer for handling, but safer for the products. Thanks for the tip, Grant.

Harold

Reply to
Harold and Susan Vordos

I'm from the caveman days.... *metal* in the microwave?????? Ken.

Reply to
Ken Sterling

Vinegar (acetic acid) would probably have worked by itself.

Jim

Reply to
jim rozen

I do not understand this. I've always heard if you put metal in the microwave that it would cause a spark. However, for years I have put small pieces of metal FULLY IMMERSED IN A CLEANING SOLUTION in the microwave, and nothing bad has ever happened. I think the resistivity of the liquid covering it may be enough to limit the current which would otherwise flow in the metal.

GWE

Reply to
Grant Erwin

It depends upon the microwave: I once had a Litton MW that could handle up to 3/4" metal. This enabled me to "cook" the old aluminum-panned TV dinners.

The one I have now will make sparks on the metallic trim of a dish.

Reply to
RAM^3

A extremely large factor (perhaps the most significant of all factors) in all cases is "How much metal stuff relative to not-metal stuff is present in the cavity?"

*EVERY* microwave I've ever encountered will produce a "lightning storm" if it's loaded with "mostly metal" and powered up. *MOST* microwaves I've encountered will cope just fine with *SMALL AMOUNTS* of metal accompanied by *LARGE AMOUNTS* of not-metal.

Then there are the tiny handful of units I've encountered that are either mis-tuned, or have ultra-huge power outputs, where even a missed snippet of the tinfoil-backed paper wrapper still stuck to the packaging will make a lightshow (and possibly even a fire) that'll scare the bejeebers out of you as you frantically jab at the stop button.

In the "fully immersed" scenario mentioned above, the quantity of cleaning solution is sufficient to overcome the metal's presence, resulting in a "no issues" situation. The Litton mentioned above was probably a low-power unit - I'd bet on it being under 700 watts, if not lower.

The "metallic trim" unit is probably a combination of high power and the exact shape of the metal in the trim - Some shapes won't spark in a microwave at any power level, no matter how hard you try. Other shapes - particularly those with "points" or "spines", will start sparking instantly when the power is turned on.

When you get right down to where the rubber hits the road, it all depends on how the material in question resonates in the microwave frequency bands. Water (which is what microwaves are tuned for) resonates quite nicely, and the radio energy gets turned into heat. Metal resonates differently, if at all, and the radio energy becomes electrical arcs.

Reply to
Don Bruder

The whole "no metal in the microwave" thing traces back to the beginnings of the consumer microwave oven, the overall lack of knowledge and the assumption that consumers would not understand the details of how to safely use metal in a microwave.

I've read many more recent microwave instructions that instruct in the use of aluminum foil to protect areas of food from overcooking, and some microwaves have metal racks to provide a second cooking level.

The real problem area are sharp points that concentrate the microwave energy and act as lightening rods and various small pieces of metal like twist ties and metallic trim on plates which will overheat.

I've scared friends when I've put entire stainless steel bowls in the microwave to warm the contents. The bowl has a rolled edge so it will not readily concentrate the microwave energy to cause arcing. The bowl also contains a reasonable amount of contents to absorb the energy.

When I'm microwaving something that will need to be stirred frequently, I'll simply leave the metal spoon in the container and insure that the handle is not too close to the walls of the microwave. Much easier than taking the spoon out constantly and having it drip on stuff.

Pete C.

Reply to
Pete C.

This is exactly it. As long as there are not regions of significantly different potential, there will be no arcs. Smooth transtions will not cause arcing.

If you want to prove it tear off a piece of aluminum foil and stick it in the microwave. Nothing will happen. Now take the same piece and crumple it up and flatten it back out loosely. There will be all sorts of wild arcing across the peaks.

JW

Reply to
jw

I agree, although perhaps not quite as fast.

Harold

Reply to
Harold and Susan Vordos

Actually not.

800 Watts according to its specs.

Its ability to handle metal was one of its best selling points - along with being $100 cheaper than the competing Amana.

It was Litton's top-of-the-line in 1974.

At last report, it's still going strong.

Reply to
RAM^3

Cool :)

"Dino-tech" in action :)

I wonder what made it more "metal-proof" than others? Maybe the tuning?

I just plain don't recall what the brand was (gimme a break! It's been almost 20 years!), but mom had this ancient thing that you couldn't kill if you drove over it with a tank - and if you tossed a wad of tinfoil into it, it would make a nifty light show :)

Thing lasted for years, but finally went tango-uniform when mom was on a cleaning frenzy and knocked the nearly full bucket of ammonia water she as using on the windows onto/into it. Even after rinsing and drying repeatedly, it never recovered. I expect the ammonia probably attacked the copper traces on the control pad.

Reply to
Don Bruder

I suppose the sharp edges of gold rings on cups are the edges themselves and not the band of metal that fuses and pops. I think currents are generated and arcs are another thing. Steel is high enough to inhibit current - eddy currents... Al gold and copper isn't .

Martin Martin Eastburn @ home at Lions' Lair with our computer lionslair at consolidated dot net NRA LOH, NRA Life NRA Second Amendment Task Force Charter Founder

jw wrote:

Reply to
Martin H. Eastburn

| > The real problem area are sharp points that concentrate the microwave | > energy and act as lightening rods and various small pieces of metal like | > twist ties and metallic trim on plates which will overheat. | >

| This is exactly it. As long as there are not regions of significantly | different potential, there will be no arcs. Smooth transtions will not | cause arcing. | | If you want to prove it tear off a piece of aluminum foil and stick it | in the microwave. Nothing will happen. Now take the same piece and | crumple it up and flatten it back out loosely. There will be all sorts | of wild arcing across the peaks. | | JW

I had a microwave with a factory metal rack in it. Messed with some folks' heads for sure!

For a fun trick, take that AOL CD and nuke it for a second or so. Very cool patterns. The eddy currents swirling all over the place blow thin places like fuses, making for some nifty but brief fireworks. If you can magnify the viewing as much as possible, you will find some really cool patterns burned into the aluminum film. The surface isn't so smooth anymore, though!

My 10 year old daughter put a Wendy's burger, with foil wrapper in the nuker the other day, then walked away. Burned away some of the plastic coating on the inside of the door screen where the foil came close. I cleaned up what I could, cut the bad plastic away, and put on some 3" clear electric tape to make it as invisible as possible. Kinda hard to get the crud that blew through the grid into the door cavity, though, and it fogs up on occasion, which is a real PITA. I never saw what the burger and wrapper looked like; that would have been cool.

Reply to
carl mciver

I just salvaged our old 1980 microwave - now we have a new higher power higher tech one. It was a monster - and it lasted. Fuse was ok - scrapped out lots of stuff. It had a metal rack as well and a metal tip thermo probe (metal wires) .

I think the idea is wavelength - if not a resonant size then it won't heat or absorb.

Like Radar on naval ships. I have seen Navy lock down doors that are sawed in two non-alike sizes. Semi-dutch like. When they fired up the 200' antenna (big baby) it worked just fine but made a door red hot and a couple of other things on the ship. The door was the only egress that was nice into or from the compartment. There was a cable way for emergencies...

My coffee mug had a gold ring around the rim - was heated once and the ring opened.

What did the final dead - I bet the filament burnt - three large potatoes cooking. High power load I suspect.

Martin Martin Eastburn @ home at Lions' Lair with our computer lionslair at consolidated dot net NRA LOH, NRA Life NRA Second Amendment Task Force Charter Founder

carl mciver wrote:

Reply to
Martin H. Eastburn

Emphasize the 1 or 2 seconds. Anymore and the thing starts burning and you will never get that smell out of the microwave! It is pretty cool looking.

JW

Reply to
jw

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