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Branding Keys Typewriter is a manual typewriter that
types
without using ink, burning the letters unto the paper
instead.
This is possible because the individual letter forms all
contain miniature heating elements that make them
glow
red hot. This means that instead of making an ink
impression
on the paper when typing, they each brand a
tiny letter form unto its surface immediately on impact.
A dampness control mechanism, fed by a small reservoir,
ensures that the paper never catches fire. The energy to
heat the keys comes via a foot treadle (similar to that of
a
manual sewing machine) connected to a simple
generator.
You must use your branding typewriter carefully as
mistakes are impossible to correct, but the results are
worth the investment and additional effort.
Type Metal
https://en.wikipedia.org/wiki/Type_metal
Low-melt alloy; most durable is liquid at 330° C [8th of 7, Dec 24 2019]
the strikers are actually called type hammers
https://www.explain...com/typewriter.html
[xenzag, Dec 24 2019]
A Field Guide To The North American Utility Pole
https://hackaday.co...rican-utility-pole/
[Voice, Dec 26 2019]
Electricity in North America
https://www.energy....rature%20Review.pdf
[Voice, Dec 26 2019]
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Annotation:
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If the mechanism is enclosed beneath a transparent cover, the volume can be inerted with nitrogen thus removing the need for damping. The paper emerges through a slot with a silicone rubber seal, perfectly dry. |
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I can find no fault with this idea. Damn. |
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Allow us to assist. Hint: a "golfball" wouid be much more efficient and practical than individual type bars. |
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Inefficiency only makes it better. |
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It has to be the old manual typewriter with the
individual strikers, all poised together in a perfect
curve, with just the inverted letters glowing red
hot ready to spring forward into action. |
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The alloy from which the type is cast will melt and run away long before it reaches red heat. |
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A golfball machined from a radiothermal plutonium isotope would require no external energy source and would continue to operate perfectly long after the owner had expired from acute radiation sickness ... |
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That's for Linotype machines that use what used to
be called 'hot metal' - These typewriter keys are
very hard and made of some kind of toughened
steel that won't be bothered by being red hot. |
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We suggest sintered tungsten, then. Iron and its alloys will oxidise and form scale, degrading the sharpness of the typeface - tungsten won't do that even at sustained high temperatures. |
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Could there be a very high voltage between the type hammers and the paper, so that the letter is branded by arcing as the type hammer approaches the paper? |
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The arc would significantly disrupt the structure of the paper, making it likely to tear & fail. |
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The paper is an excellent insulator - in fact, paper is used as the dielectric in some capacitors. So a high voltage is needed between the typeface and the platen to get the arc to strike through the paper. |
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When it does so, the current (and therefore energy) will be excessive. The heat breaks down the cellulose fibres in the paper in the vicinity of the arc, driving off the bonded water and leaving the carbon (which is conductive). This is a known failure mode for capacitors. |
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Because carbon is an electrical conductor, the path resistance of the arc suddenly drops, allowing a greater current for a given voltage, so the energy transfer increases, rapidly heating and thus degrading the paper in the vicinity of the arc path in a cascade failure. The plasma channel expands rapidly; the area of the arc is related to the width by square law <Points at diagram on whiteboard/> |
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Now, the arc was struck before the typehead actually contacted the paper, so the distance is still decreasing. Having converted the insulating paper to conductive carbon, the arc increases in intensity as the distance shortens and starts to melt the surface layer of both the typeface and the platen. The liberated metal vapour further decreases the resistance of the arc. Finally, the typehead strikes the the platen - displacing the frangible carbonised remains of the paper - and extinguishing the arc. |
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The two surfaces then become welded together, providing a very low resistance path for the current. Since the power supply for the typewriter is an industrial arc welder, capable of delivering many kW of power at hundreds of amps <Giggling/>, Ampere heating causes the type bar to glow red, then yellow. Finally it sags and melts, but as it disintegrates the molten metal vapourizes and forms the perfect medium for a much bigger arc to strike and sustain. The entire output of the welder, which is buzzing loudly and jumping off the floor because someone has jammed a screwdriver into the cutout switch, is now being fed into a small item of office equipment <Hiccuping laughter and arm flapping/> which is totally unable to contain it. Plastic melts and ignites, springs twang, the structure explodes outwards. |
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At this point the secondary contactor operates, connecting the welder's output cables to a nearby 250 kV AC distribution line. The arc fills the entire room with blinding blue-purple light. The roof lifts and the walls blow outwards, masonry shrapnel mowing down all those fleeing from the catastrophe, leaving them as bleeding, twisted bodies as the fire boils over them. Gas mains shatter from the shock, adding to the fireball. Overloaded, the substation feeding the arc tries to open its breakers, but someone has bound the contact arms to the pillars with many turns of thick copper wire, meaning that the circuit cannot be broken. Now, the whole power of the electricity network is feeding the inferno, and a vast fireball erupts, overloading multiple generating stations and plunging huge areas of the country into darkness for days MUHWHAHHAHAHAHAHAH ! AHAHAHAHAHAH ! YOU FOOLS ! YOU SAID IT COULDN'T BE DONE ! HAHAHAHAHA ! |
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<Takes three little pink pills washed down with half a can of Carlsberg Special Brew/> |
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For homework, please review the next chapter, "Ten uses for an All-In-One printer you may not have thought of". We will discuss this next time. |
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<Exits, twitching slightly/> |
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Bravo! but there's something magical about seeing
those little letter forms glowing red hot as they
rest in anticipation of typing my latest letter to
the Australian ambassador, lambasting the
collective idiocy of his entire country over their
attitude to the global warming that's burning the
place into oblivion. |
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Yes, they should have adopted a more sensible policy years ago; cut down all the trees, and burn them for fuel. Job done ! No more bushfires ! |
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You could put a few in a tree museum, of course - but pave the rest of the cleared area, and make it into a parking lot. |
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Bravo [8th], but you forgot the step-down transformer, which failed, isolating the circuit one down from the substation. And the substation's primary emergency breaker. And the substation's transformer and its fuse. |
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// you forgot the step-down transformer, which failed, // |
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... by a dead short between primary and secondary... |
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// . And the substation's primary emergency breaker. // |
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... into which person or persons unknown had thoughtlessly inserted a length of scaffolding pole, jamming it in engagement... |
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// And the substation's transformer and its fuse.// |
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... which had by some peculiar mischance ended up with the input and output cables connected to the same terminals. Careless, careless... |
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An interesting idea but I foresee difficulties in
winding in cattle between the platen and the
paper table guides. |
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