Guide to Autopoint and Dur-O-Lite Spiral Pencils
A Working Paper


Robert L. Bolin

This is a working paper based partially on conjecture.  I would appreciate any comments, corrections, and additional information. 

Return to the Web Resources page.


Spiral pencils and Mark Sense Technology
The Three Basic Designs
Commercial Models
Dur-O-Lite Models
Autopoint Models
Institutional Customers
The Bell System
US Government
H&R Block
Wooden Spiral Pencils

Spiral Pencils and Mark Sense Technology

In the late 1930s, the Dur-O-Lite Pencil Company, developed a pencil with a distinctive spiral mechanism. The mechanism is shown below in instructions for "How to Reload Your Spiral Pencil" from the 1985 Dur-O-Lite Catalog.

The spiral pencil design can be seen in this pencil made with clear plastic.

Also in the late 1930s, IBM introduced "mark sense" technology for use in punched-card data processing operations. A pencil could be used -- in conjunction with certain special equipment -- to record data on punched cards.  Mark sense applications required use of a special lead with high graphite content called "mark sense" or "electrographic" lead. The mark sense or electrographic lead was 0.46" (1.1mm) in diameter which was standard in the 1930s. 

The spiral pencil proved useful for mark sense applications because it could hold a long piece of lead. Dur-O-Lite sold many thousands of spiral pencils to AT&T which used mark sense technology to record long distance calls.

In the mid-1950s after the Dur-O-Lite patent expired, the Autopoint Company, a rival pencil company in Chicago, reverse engineered the spiral pencil and began producing it. Autopoint took great care to make its pencil appear identical to the Dur-O-Lite models. Autopoint expressly went after the Western Electric contract for electrographic pencils. 

Autopoint was able to outbid Dur-O-Lite and took over many of the contracts with institutional customers.

The development of the spiral pencil and the rivalry between Autopoint and Dur-0-Lite are outlined in my Web page called An Autopoint/Dur-O-Lite Mystery ¡ SOLVED !

The Three Basic Designs

  1. In the original spiral pencil, the tip assembly is about 5 inches long and there is no storage space for leads in the pencil. That pencil can hold a piece of lead about 4 inches long. Some of those sprial pencils had clips, but many do not. Three main variations exist:
    • Some are topped with erasers like conventional Autopoint or Dur-O-Lite pencils. 
    • Some are topped with an elegant metal "dialing ball." 
      • Dur-O-Lite sold pencils with the dialing ball to its commercial customers as well as to large institutional customers. 
      • Autopoint also made a version with the dialing ball but did not sell it to their commercial customers because Autopoint had been selling an excellent pencil with a plastic dialing ball since the 1920s. 
    • Some are topped with a plain plastic cap.    Both Dur-O-Lite and Autopoint made dialing balls on metal sleeves which fit on plain spiral pencils.  Also, a non-rotating plastic dialing ball could be fitted on the plastic cap.

  2. Both Dur-O-Lite and Autopoint made pencils with a short spiral mechanism like the one shown below. 
  3. The tip assembly is about 2¾ inches long. That pencil has a storage space for leads under the eraser like a conventional Autopoint or Dur-O-Lite pencil. 

  4. The third variant is a double-ended pencil in which two of the shorter tip assemblies are used for different color leads. 
    • Dur-O-Lite sold a pencil with a metal body and a pocket clip.
    • Autopoint made a version consisting of two short pencil segments held together in the center with a ¾ inch metal band. Both pencils with a black and a red segment and with two black segments have been seen. The Autopoint double-ended pencil had no pocket clip. That pencil did not appear in Autopoint commercial catalogs. Probably Autopoint did not advertise it to commercial customers because they had a double-ended mechanical pencil of another design that they had sold very successfully since the 1920s.

Commercial Models

Dur-O-Lite Models

Dur-O-Lite sold spiral pencils to their commercial customers as well as to large institutional customers.

Several models are shown on this page from the 1985 Dur-O-Lite catalog:

The "#560 DU-AD" is the double-ended pencil. The other models are: 
Hexagon Round
Lead Size .046" (1.1mm) .036" (0.9mm) .046" (1.1mm) .036" (0.9mm)
Short Spiral #111 #T-111 #111R #T-111R
Long Spiral #113 #T-113 #113R #T-113R
For many year .046" (1.1mm) diameter lead was "standard."
In 1938, .036" (0.9mm) diameter, "thin," lead was introduced. 
A single groove around the tip distinguishes pencils intended for use with "thin" lead. 

The "Steel Ball Dialing Pencil," #183, is shown on this page from the 1985 Dur-O-Lite catalog.

Autopoint Models

Autopoint sold spiral pencils to their commercial customers as "Pacemaker." There were four variations:
Lead Size Long-Spiral Short Spiral
Standard Lead No. 90 No.90S
Real-Thin Lead No. 190 No.190S
For many year .046" (1.1mm) diameter lead was "standard." 
In 1938, .036" (0.9mm) diameter lead, called "Real Thin" by Autopoint, was introduced. 
As with the Dur-O-Lite pencils, a single groove around the tip distinguishes pencils intended for use with "real-thin" lead.

The Pacemaker was listed in a sales flier issued with the Autopoint Newsletter, Vol.1. No. 2, September 19, 1960.  

The Pacemaker is shown on this page from the 1969 Autopoint catalog:

Instututional Customers

The Bell System

As purchasing agent for the Bell System, Western Electric bought a variety of spiral pencils in various colors from Dur-O-Lite and Autopoint in the 1940s, 1950s, and 1960s.
  • The most distinctive is the pencil with the elegant "dialing tool." The "dialing tool" was patented by Bell Labs in 1941. 
  • KS8300 appears to be a Bell System part number.  As mentioned above, Dur-O-Lite made a version of the dialing ball on a brass sleeve which would fit on a spiral pencil with a plain plastic cap.

    Autopoint also made a version of that pencil for the Bell System.  "Autopoint CHICAGO U.S.A." appear on the metal band below the ball.   Also, Autopoint made a version of the of the dialing ball on a stainless steel sleeve.   "Bell System" and "KS8400" appear on the sleeve.

    An unidentified manufacturer also made a version of the dialing ball with a solid metal ball and a stainless steel sleeve.    "Bell System" and "KS8400-1" appear on the sleeve.

  • Although "BELL SYSTEM PROPERTY" pencils in various colors -- including dark blue, powder blue, and yellow -- exist, AT&T appears to have used color coding for its mechanical pencils part of the time. This pattern is apparent:
    • Red was used to identify pencils intended for use in "Mark Sense" operations. They are marked "BELL SYSTEM PROPERTY" and labeled "MARK SENSE LEAD." They do have erasers. Some have no pocket clip and no brand name on them. On some, the word "Autopoint" appears on the ferrule holding the eraser. Some do have a clip with "Autopoint" on it. 
    • Green indicated pencils for general office and field use. Those pencils were marked "BELL SYSTEM PROPERTY" but not labeled "MARK SENSE LEAD." Some dark green "BELL SYSTEM PROPERTY" pencils have plain plastic caps and no pocket clips. Others have erasers and clips. The clips have the brand name of the maker on them -- either Dur-O-Lite or Autopoint. Some green "BELL SYSTEM PROPERTY" pencils used 0.046 inch (1.1mm) diameter lead, and others used 0.036 inch (0.9mm) diameter lead. 

      Note: Dur-O-Lite used the convention of incising a line on the tip to indicate that the pencil used 0.36 inch (0.9mm) lead. Since that lead had been introduced in 1938, the Autopoint Company had been marking pencils using 0.36 inch (0.9mm) lead with "FOR Real Thin LEAD." When it started manufacturing spiral pencils, the Autopoint Company adopted the Dur-O-Lite convention. Later it adopted that convention for its product line. Below is a picture showing the line incised on a pencil tip.

US Government

The US Government bought "MARK SENSE" spiral pencils. I have only seen copies with the "Autopoint" brand on them.


Esso bought spiral pencils. 

H&R Block

Apparently, the Blocks brothers liked the dark mark that mark sense leads made. They bought large numbers of spiral pencils from both Autopoint and Dur-O-Lite. Their pencils are not equipped with pocket clips. One person who worked for Block explained to me that they filled out returns in pencil and then Xeroxed them to "fix" them. The copy was signed and sent in.  

Wooden Spiral Pencils

In the early 1960s Dur-O-Lite introduced a cheap disposable wooden pencil based on a variation of the basic spiral mechanism. That pencil was developed in response to Western Electric's request for a cheaper alternative to the spiral pencils.

Over a period of 30 years, Dur-O-Lite sold millions of those "Keen Point" wooden mechanical pencils to Western Electric and many other customers.