[GreenKeys] introduction and Teletypesetter

[dmm at lemur.com]

Roy Morgan wrote:
>I think that if your teletype machine or any part of it gets as hot as  
>the lead in a typsetter, then your machine is in big trouble!  heheh.

Probably, yes :-)
The factory-recommended temperature for a Linotype pot was 535 degrees.
The Ludlow Typograph crucibles (a simpler linecaster) ran a bit hotter,
at 565 (12-point mold) to 585 (6-point mold).  Last year I had the
opportunity to help run a Thompson Typecaster for a day, casting 
individual types.  There we ran the pot at closer to 700 degrees,
but the alloy in use was quite different.  There are all quite low
temperatures compared to many casting processes, but still enough
to burn paper and make most oils rather unhappy.

Linotype alloy was actually the "eutectic" alloy of lead/antimony/tin:
84.5% lead, 11.5% antimony, 4% tin.  This is the alloy which 
both has the lowest melting point and which solidifies instantly
(vs. going through a slushy phase).  It melts and solidifies at
464 degrees.  Printers tend to refer it as "typemetal" or
"printers' metal" rather than lead, as a "lead" is a particular
piece of spacing material in letterpress printing.


>I remember a boy scout trip to the local newspaper where they used hot  
>lead to cast cylindrical press "plates" to print the paper that we got  
>every day. They Also used hot lead in the typsetting process to create  
>cardboard-like molds to make the "plates". Vivid memory from a LONG  
>time ago!

That would have been stereotype plate making.  The cardboard "molds"
were called "flongs" (a great word).  Stereo plate making is my
candidate for the technology with the greatest ratio between its
importance when in use (very high) and the degree to which it is
currently remembered (forgotten).  Even letterpress printers don't
remember that it was done (except those who worked in newspapers).
Yet it was the technology which enabled the high-speed rotary press
(rotary presses need curved plates; type as set is flat).

Gerry Block wrote:
> These may be better than Teletypes.  Isn't hot metal better than hot  
> oil?

A friend of mine is a retired tool and die maker.  A couple of weeks
after I hauled home my first two linecasters, he walked into the shop.
He stopped abruptly, breathed deeply, and smiled.  The smell of the
old machinery took him back to his tool and die shop.  It's the same
everywhere, or at least across many older technologies.


Anyway, I don't mean to go on too much about this; this is a 
TTY list, after all, not a hot metal list!  But thanks for the several
replies I've received, both on-list and offlist.  Much appreciated.

Regards,
David M.
===
Dr. David M. MacMillan * dmm at lemur.com * www.lemur.com & www.CircuitousRoot.com

   First do no harm. (Primum non nocere.)
       - possibly Galen; see also Hippocrates (Epidemics, Bk. I, Sect. XI.)
   The first rule of intelligent tinkering is to save all the parts.
       - Paul Ehrlich (1854-1915); Aldo Leopold