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Doctor Olds
I Need A Remedy For What's Ailing Me.
Premium,VIP
join:2001-04-19
1970 442 W30
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reply to robbin

Re: Well Water Black Metal Question

said by robbin:

Yeah -- I've looked that up also. Strange thing is I remember playing with my etch a sketch with a magnet when I was little. This would have been one of the original ones in the early sixties. I remember it acting as though it was extremely attracted by magnetism. I remember the particles lining up and even being attracted to each other to form "wiskers" around the magnet. Hmmm

This is a good source.

»www.nytimes.com/2013/02/04/busin···tml?_r=0
quote:
The complete eradicability of an Etch A Sketch drawing is born of the toy’s simple, abiding technology.

The underside of the screen is coated with a fine aluminum powder.
The knobs control a stylus hidden beneath the screen; turning them draws the stylus through the powder, scraping it off in vertical or horizontal lines that appear on the screen as if by magic. (An early French name for the toy was L’Écran Magique, “Magic Screen.”)

To erase the image, the user shakes the toy, recoating the screen with aluminum; tiny plastic beads mixed with the powder keep it from clumping.
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Raphion

join:2000-10-14
Samsara
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Aluminum, like any non-magnetic conductor, becomes temporarily magnetized in the presence of a changing or moving magnetic field, due to currents being induced within it. Maybe moving a magnet over the powder would temporarily magnetize them causing them to line up with one another.

Or maybe Robbin's memory is actually of something like »en.wikipedia.org/wiki/Wooly_willy ?


robbin
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join:2000-09-21
Leander, TX
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Wooly Willie -- Hmmm. Maybe my memory is confused. If so, not too much as Wooly Willy had a magnetite beard so that kind of keeps this on topic.

"Wooly Willy went on to become one of the 40 most popular toys produced during the 1950 to 1980 period. It was frequently copied around the world. One set made in Japan even had "Made in Smethport, Japan." Fortunately the copiers were never willing or able to make the engineering effort to duplicate Willy's quality featurers----special magnetite powder, a sturdy anti-static plastic dome, thick display card and a strong drawing magnet."

»www.smethporthistory.org/smethpo···page.htm

The site is an interesting read. I recognize another one of my early toys which was on it - "The Electric Toy Set". I remember the fish.



SparkChaser
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Downingtown, PA
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Reviews:
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reply to Raphion

said by Raphion:

Aluminum, like any non-magnetic conductor, becomes temporarily magnetized in the presence of a changing or moving magnetic field, due to currents being induced within it. Maybe moving a magnet over the powder would temporarily magnetize them causing them to line up with one another.

You need a strong magnetic field and continuous aluminum to get an electromagnetic effect. Won't work with powder.

If the well wasn't so deep I wonder about contamination. Magnetite is used in toners (Xerox) , inks US currency, etc.

Interesting problem.
--
"Facts do not cease to exist because they are ignored." - Aldous Huxley

"When a true genius appears in the world, you may know him by this sign, that the dunces are all in confederacy against him." Jonathan Swift


pende_tim
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Andover, NJ
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Reviews:
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I don't really think it is from any surface contamination, like toner etc. Since the well is pretty deep and there is a casing down about 50' it is "stuff" from the earth.

The pieces are actually quite large, relative to toner and ink. They are slightly smaller than the size of pepper mill ground pepper.
--
The difference between genius and stupidity is that genius has its limits.