return to main 1401 Restoration Page

IBM cards used round holes until the early 1930s,
then rectangular holes

Also, how do you make rectangular holes in hard steel dies?
and the IBM 1442 card punch used tungsten carbide punch dies

Table of Contents

from Alan Jones

I know nothing about how IBM did the rectangular punches. But George Judson, who was on the Pa. Turnpike job (I guess IBM got the job after Remington Rand) told me that they went from an 80-column punched card to a 40-column punched card because the card was held by hand by the collector as he inserted it in the machine. With the narrower punches, along with the guy�s (they were always male in those days) hand moving, they didn�t always read correctly. Doubling the width of the holes solved that problem. And, I guess, 40 columns were able to contain the information they needed.


Alan Jones
AlanJones @ stny . rr . com

from Grant Saviers
Subject: Re: [FWD: RE: Who Invented the 80 column, Rectangular Hole Punched Card?]

From: Grant Saviers
Date: Sun, Dec 30, 2012 10:54 am
Cc: Jim Strickland , Robert Garner ,
"Stan Paddock, " , "Frank King, " ,
Susan Sherwood

Some speculations and what I recall from a conversation some time ago in the 1401 room about "how did they do that?". IIRC, the die plate is two parts, a thick (.15"?) plate with coarse tolerance holes covered by a thin precise tolerance hole plate. And then each punch is hand fitted by judicious hand lapping.

So, how did they make these in 1929? The thick plate could be punched soft then hardened and ground flat. That way the plate manufacturing die set would last longer. Also, more die and punch relief (clearance behind the working surface made by tapering the punch and sometimes the die) is needed as thickness increases.

There is a slow speed hydraulically actuated punching technique for precise holes in thicker materials, but I forget the name of that process. It would make sense to broach the holes in either (thick or thin) of the production dies if the tolerances couldn't be held with conventional punching. I think broaches were common then.

They are not too difficult to make and can be resharpened fairly easily. Most likely all of the production dies and punches were hand lapped for fit and finish after however they were punched or broached. Of course, round hole dies and punches are the easiest to make and that would be a another starting point for broaching but the geometry of the rectangular hole then requires the broach to remove a lot of material, not good.

Also, the broach would be pretty fragile, starting with the something less than final rectangular hole width as its diameter. I think that argues for rectangular or oval punched holes as a starting point for broaching.

Perhaps the thin part was made by photo etching. The process goes back to the 15th century for print making. A little googling didn't turn up any history relative to photo etching holes, it seems everybody is interested in deep UV processes for 15nm semiconductors.



Part of Punched Cards - A brief illustrated technical history by Douglas W. Jones, Univ of Iowa

Punched Cards
A brief illustrated technical history

Part of the Punched Card Collection
by Douglas W. Jones
THE UNIVERSITY OF IOWA Department of Computer Science


The overall dimensions of punched cards used for data processing have remained the same since Herman Hollerith settled on the card format. 7 3/8 inches wide by 3 1/4 inches high by .007 inches thick. Prior to 1929, this was a standard size for many US banknotes, and Hollerith apparently chose it so that he could store cards in boxes made for the Treasury Department. Eventually, most of a century after Hollerith's work, these dimensions came to be standardized as the EIA standard RS-292 media 1 punched card.

The cards used to record the data from the 1890 census had 22 columns with 8 punch positions each (although there was room on the card for a total of 11 punch positions per column). The coding used on those cards did not encode data in columnar fields, but rather, each punch position was assigned a specific meaning. Hollerith continued tinkering with the way data was encoded, adding rows and columns to meet the needs of new applications. 24 colums of 10 positions each in the 1900 census (inferred from the 1900 National Geographic article), although published images of punched cards from the railroad industry in the same era all show 12 row cards with 36 punch positions per card. Cards used in the 1910 census apparantly had 27 columns of 12 positions each. By the end of the 1920's, IBM's established line of punched-card machinery used 45 columns of round holes per card and 12 punch positions in each column.

In 1928, Hollerith's company, now renamed IBM, introduced the rectangular hole 80 column format, almost doubling the amount of data that could be recorded on a card, and by the mid 1930's, IBM was predicting that round-hole cards would soon be things of the past. IBM's 1928 design was the basis of what, decades later, came to be the standard punched card, eventually defined by ANSI X3.21-1967 governing the holes in the card and ANSI X3.26-1980 governing the use of the Hollerith code to encode alphanumeric data on cards.

[round hole sperry punched card]
A high resolution scan is available.

In fact, the round-hole format remained in use into the early 1990s, but in a very limited set of applications! The last use I am aware of is toll tickets on some eastern turnpikes. There are two reasons that the round hole format survived: First, IBM had a patent on their new rectangular format, so competitors were forced to limit themselves to the old format. Second, Remington Rand, one of IBM's major competitors in the pre-computer era, moved from Hollerith's code to a 6-bit code that allowed 90 columns of text to be stored on the old 45 column cards. When Remington Rand bought UNIVAC, they naturally integrated their 90 column card format with UNIVAC computers. In many ways, the UNIVAC card code was superior to IBM's "improved" rectangular hole version!

Oliver J. Jones wrote me that, in addition to surviving on some eastern turnpikes, UNIVAC's 90 column cards also remained in use through the 1960's at Macy's Department store and Lerner Stores, in the retail sector, the US Navy Medical Supply office and the Polaris missle control system, in the military sector, the New York City Tax Department, Long Island Lighting, and more. He sent along an image of the cover from a Remington Rand brochure and a promotional poster.

Mike Albaugh wrote me that he helped dismantle a UNIVAC SS90 system in 1974 or 1975 that had been in use up until the week before. He also saw a similar UNIVAC system in use at the Concord Naval Weapons Station around the same time. These apparently used 90 column cards.

If you look at the punched card equipment sold by IBM after 1931, you will find complete hardware support for IBM's alphanumeric Hollerith code, but you will also find that the majority of the machines sold were limited to numeric applicatons. At a time when, for example, the University of Iowa was punching student names on cards using the Hollerith code, other universities were developing 4-digit numeric encodings of common names so that they could avoid the need for the more expensive alphanumeric equipment.

The book Practical Applicatons of the Punched Card Method in Colleges and Universities, edited by G. W. Baehne an published by Collumbia University Press in 1935, contains an excellent summary of the state of the art in punched card data processing in 1935, including an appendix that appears to be a reprint of IBM's catalog for that year and many illustrated descriptions of typical applicatons.

When cards were used to store fixed-format information for data processing applications, they were almost always printed with format information, so that a casual reader could easily determine what punches on the card held what information. This printing could be quite specialized to one application, or it could merely set off fields in a standard way, with no indication on the card of what the purpose was.

[punched card retail form]

The card shown here is typical of those used with IBM's line of card processing equipment from the 1930's onward. This particular example was printed for a range of retail applications where it must have been expected that the customer would handle the cards, as indicated by the warning: Do not fold or mutilate. This warning would be unnecessary if the card were only to be handled by data processing workers. While most fields of this card have no clear purpose, it contains an interesting and very specialized feature, a tab the cashier was supposed to tear off along a perforated line when the card was processed. A card with this tab removed would be seen by card processing equipment as having a punch in column 1, row 12.

It is important to note that the typical card processing applications from the 1890's to the 1950's did not require the use of computers! A deck of cards from a retail application, for example, could be sorted by the category field on a card sorter, and then each category could be run through a tabulating machine to sum the price fields of all cards in that category or similar accounting functions.


Conversation with Don Rex - Boca Raton, FL - Jan 2013
He said that the IBM 1442 uses "his" tungsten carbide punch die.

He was really not very interested in steel punch dies - old hat when he was in Endicott - He said they were made there, but he didn't remember visiting that factory. Since the process was not new he probably would not remember the visit anyway - He said that of course they used stepped broaches to make the holes rectangular, and then hardened the steel -

Indeed he knew Clair Lake of the rectangular data hole patent.

In the mid 1950s, working on the hydraulic paper handling system for the printer for the non-product 1133 ( never announced ) in Endicott, their group contributed their mechanism to the 1403 printer group - The only difference was that the 1403 used a different output shaft rotation direction -

He worked in San Jose on the punch for the System 3 which came out just as disks were taking over from punched cards -

He eventually retired, as an IBM Fellow - He does not want a computer in his home - apparently had enough of 'em at work ;-))

Stan's list for square or irregular holes
Electrical discharge machining