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IBM Punched Card Stock Specifications

- You can buy ANSI spec X3.11, info from Al Kossow

IBM Punched Card stock is paper :-)) 0.007 +- 0.0004 inches thick with rather tight specifications.

"Card size is exactly 7 3/8 by 3 1/4 inches (187.325 mm 82.55 mm). The cards are made of smooth stock, 0.007 inches (180 m) thick. There are about 143 cards to the inch (56/cm). In 1964, IBM changed from square to round corners.[42]"

A bit of background - added November 8, 2018
from Dag Spicer, "Hey, an older gentleman from Sacramento just dropped by the Museum this morning unannounced and offered us this object. It was used by the State of California to measure the dimensions, including thickness, of the sometime non-IBM punched cards they used for government purposes."
Ah, the punch card wars. "Everyone" wanted to make a bundle selling punch cards under the price and quality leader, IBM.
I presume gauges such as these were to
    - verify competing cards were "up to specification"
    - convince IBM to let customers to service/adjust IBM machines to better run the cheaper cards.

Specifications of paper characteristics you never dreamed of -
Well folks - time to get personal -

After working for G.E. and CDC, for about 5 years each, I worked for 17 years for Measurex - a paper process control company :-)) Measurex has since disappeared into the maw of another corporation :-((

We leased our process control scanners, gauges, and software to paper companies to help them control their paper making machinery.

If you ever get a chance to visit a paper mill - jump - it is unbelievable - HUGE equipment -
- - - YouTube (Wisconsin),
- - - another slow start, more complete
- - - and another (British) has a slow start, shows Measurex control display and later a scanning gauge on-sheet

Wikipedia now has a rather good description -

A quick overview

  1. a huge pressurized "head box" up to say 10 meters wide with tons of thin (wood pulp) mush
    - continually being refreshed from a 16 inch pipe from ...
    - with paddles to gently keep the mush uniform
  2. a thin ribbon of the thin (wood pulp) mush, 10 meters wide, from the head box
    - streaming at up to 60 miles per hour - 1500 meters/minute
  3. on to a "wire" screen belt say 11 meters wide and 30 meter long moving at the same speed
    to drain and vacuum out as much water as practical
  4. to the cooch roll, to squeeze and vacuum out as much more water as practical
  5. through huge drying sections say 75 meters long and 4 stories high
    with huge steam heated drums which dry the paper to about 6% moisture,
  6. through or past the calender stack depending of requirements
  7. to huge take up rolls that accumulate about 10 tons of paper each,
    - when full an empty roll magically begins to accumulate the streaming paper.
(Roland Sundstrand has kindly updated some of the above numbers. :-))

The same equipment (in general) (but with different pulp recipes and machine settings) can make news print, paper for books and magazines,
and - ta ta - IBM Punched Card stock. (IBM cut it into cards and printed on it.)

However, two kinds of paper used to give paper makers fits - very difficult to make spec -
- Xerox paper
- IBM Punched Card stock

Although technology now helps measure and control some parameters,
Papermaking is still very much an industrial art.
The paper makers on the machine are union members,
*but* get paid by the ton of on spec paper! Serious, thoughtful, alert, cooperative work!

This is not a paper makng lesson - a fascinating field in its own right.
The following are the specifications that IBM insisted paper makers meet.
Fail to meet spec on what you ship,
and your freight car(s) of multiple 10 ton rolls of card stock are returned to you :-((
- with you owing freight each way :-((

The tale of how the following documents got to my scanner and CHM is interesting.
Dan Ashton of Pleasanton visited the 1401 being restored. We got to chatting and he mentioned that he had specialized in making IBM card stock for Crown Zellerbach (now Crown van Gelder). Having had an extended interest in helping folks meet demanding customer specifications, I asked if he happened to have specifications for IBM card stock. NO - but he had prospects :-))

A month later Roland Sundstrom of Orinda called saying that he was a friend of Dan Aston and he had gotten specifications from old CvG friends in Holland (of the Netherlands) .

And here are the specifications !! :-))
- about 200 K bytes each -

Page originated February 2, 2005
Broken YouTube link replaced Feb 2012