You are currently viewing Mechanical Pencil Month – Day 16: Cone v. Cylinder

Mechanical Pencil Month – Day 16: Cone v. Cylinder

Over the last few days, the question of point shape has come up more than once. There was the Staedtler REG with its throwback conical point in an age of cylinders and the Pentel PG1000 which just couldn’t decide. All of the compass inserts mentioned on day 14 had conical points. Representing the cylinder camp there is of course the Rotring 600, along with most “serious” draughting fineliners of the last couple of decades. Even some recent 2 mm leadholders have cylindrical points, such as Rotring’s Rapid Pro and the Staedtler 925 35-20B.

It is one of those things that could just be dismissed as a matter of style, yet the relatively sudden appearance of the cylindrical point and the consistency of its form suggests there are other factors at play. Only as I was hunting around for overlooked oddities for today’s post did the answer present itself to me, lurking in the shadows of my K&E Leroy lettering set.

Keuffel & Esser Leroy lettering set

For the uninitiated, the Leroy system was an alternative to lettering stencils that operated on the same principle as a pantograph. Instead of being cut into a thin plastic sheet, the characters were engraved on the upper surface of a ruler-like template, the lower edge of which had a slot running its full length. A special scriber, comprising a tail pin, tracer pin and pen socket, was placed with its tail pin located in the linear slot and its tracer pin on the character to be drawn. With a tubular drawing point fitted in the pen socket, the tracer pin was carefully guided by hand around the engraved letter while the pen replicated its shape at a scale and slope determined by the scriber setting.

This was not an easy process, demanding considerable skill and practice to get even halfway decent results, but Leroy lettering was nevertheless very widely used in North American drawing offices and even found its way into comic books. The earlier sets came with a series of different width tubular funnel pens – essentially just a nib with a plunger – that could be clamped into the pen socket. Possibly as a result of customer demand, at some point K&E began to include another accessory in their sets: a mechanical pencil.

Keuffel & Esser Leroy 022 lettering set mechanical pencil

The Leroy pencil was much shorter than a conventional drawing pencil as it was intended only for use with the scriber, just like the drawing points. Most importantly of all, the pencil’s point was designed to the same dimensions as the pens, with a cylindrical neck that could be clamped into the scriber.

Keuffel & Esser Leroy 022 lettering set mechanical pencil in scriber

The earliest model I have seen had a twist-advance mechanism and took leads that were 0.020 of an inch in diameter (c.0.5 mm). This was succeeded by the pencil I found in my later set, the Leroy 022. As the name suggests, and for reasons unknown, the leads for this second generation pencil were 0.002 of an inch thicker than the original. While this difference might seem petty, the 1979 K&E catalogue still lists refills for both new and old pencils, the latter being described as the “discontinued model 61 0200 “020” Pencil” (see bottom of p. 19). Finally, some very late sets came with a 0.5 mm pencil (naturally, Dan Linn has them all).

Another change in the later sets was the inclusion of technical reservoir pens in addition to the small funnel pen points.

Keuffel & Esser technical drawing pen point detail

According to a fascinating in-depth history of the Leroy division written by a former employee (PDF here), these pens were made for K&E by Koh-I-Noor Rapidograph Company in Bloomsbury, New Jersey, while K&E returned the favour and made templates for Koh-I-Noor. To use them with the scriber, the metal point of the pen was designed in the same way as the pencil, with a cylindrical portion designed to fit the clamp. This explains why in 1976 when Rotring introduced their new Isograph pen (originally named the Rotring 2000), they broke with tradition and gave it a cylindrical point, in contrast to the conical points used for their earlier Variant and Micronorm pens (the removable nib sections were even called a drawing cone, or Kegel in German).

Around this time, Rotring also began to sell their own version of the Leroy set, known as the Controlled Lettering System.

Rotring Controlled Lettering System

This came with or without technical pens, but all sets included a small pencil insert to fit the scriber.

Rotring Controlled Lettering System scriber fitted with pencil insert

Typically for Rotring, this was entirely manual and fitted with a 2 mm lead, in keeping with the inserts used for their compasses at the time (see day 14).

Rotring Controlled Lettering System pencil insert

Contrary to the idea that Rotring were always ahead of the curve, when it came to technical pens with cylindrical metal points they were beaten by Standardgraph, who by 1973 were offering a pen to this specification.

Standardgraph Stano-pen cutaway from 1973 Technical Pens catalogue

Their catalogue text makes it clear that this was “for fitting special lettering instruments”. Standardgraph had their own pantograph lettering system, the Duograph, that appeared in their catalogues from the mid-1960s.

Standardgraph Duograph from 1960s catalogue

(Incidentally, although the Leroy scriber was patented by K&E in 1933, the idea for the lettering system goes back at least to 1922 and a German patent granted to Heinrich Kassebaum, who patented further improvements in 1925 and 1927, the latter in the USA.)

When Rotring released the 600 pencil in 1989, it also featured a cylindrical point that fitted a scriber – but only just!

Rotring Controlled Lettering System scriber fitted with Rotring 600 pencil

It seems that the black finish may have increased the diameter beyond the tolerance allowed for their metal pen points. The design of the Rotring 600 was based on their 500 pencil, first introduced around 1985 and with a chromed cylindrical point like that of the Isograph pen. Even as late as 1990, the Controlled Lettering Sets were still being sold by Rotring, so the cylindrical point may still have been an active consideration.

Since then, the Rotring 600 has gone on to inspire countless imitations and the stepped cylindrical point has become a standard feature of many professional draughting pencils, but almost certainly without any real understanding of why they are designed this way. It seems akin to the triglyphs and guttae of classical Greek temples that were once based on the features of earlier wooden temples – namely beam ends and wooden pegs – but having been translated into stone gradually lost their meaning and became purely decorative elements. Such is the fate of the cylindrical point.

Leave a Reply