Technical pen
Encyclopedia
A technical pen is a specialized instrument used by an engineer
, architect
, or drafter to make lines of constant width for architectural
, engineering
, or technical drawing
s. It has been also generally called "rapidograph", although that particular name is officially a trademarked line of products made by German company Rotring
, and by American manufacturer Chartpak, Inc. when they purchased the rights from Rotring to produce the pens in the USA under the Koh-I-Noor brand.
Most technical pens use ink cartridges which can be refilled or replaced.
s) consisted of a small pair of calipers, having one flat and one bowed leg holding ink between them. By adjusting the gap between the legs the width of the line drawn by the pen could be adjusted. Such pens, kept at a constant angle to the paper, were used for ruling lines, but not for cursive
handwriting, nor for off-hand flourishes. The Graphos technical pen introduced in 1934 miniaturized the caliper principle and made the points easily interchangeable.The Sheaffer company produced an expensive drafting set which included such pens for use on linen
prints. These sets were often presented to a draftsperson upon becoming 'time served', which is marking the end of the apprenticeship.
or other template (the ink had no immediate contact with the template's edge). Some special, more expensive nibs were equipped with tubes made of tungsten or with their tips made of synthetic precious stones, to slow their wear on hard surfaces.
. Such pens frequently came in sets of various sizes, and several pen points which were installed into the holders that also contained a filled fountain, which in turn would be screwed into a handle. The construction and amount of parts varied depending on the company, and the parts were not cross-compatible in most cases. Some later designs (like the Staedtler MarsMatic700) had especially designed channels to allow better air flow in between the wall of the external grip and the point assembly. This made ink flow more reliable. The general drawback of this group of pens is that they have to be frequently and carefully cleaned to remove all ink from the tubing, otherwise it would set and could not be removed.
For the rest of the world, the most recognized brands were Staedtler, Rotring and Faber-Castell; currently only Koh-I-Noor USA, Rotring, Rystor and Staedtler still make the traditional technical pen.
(ISO) called for four pen widths and set a colour code for each: 0.25 (white), 0.35 (yellow), 0.5 (brown), 0.7 (blue); these nibs produced lines that related to various text character heights and the ISO paper sizes.
Text (produced by an ISO stencil
template for use with the technical pens) of 5 mm in height has a stroke or line thickness of 0.5 mm, and so requires a brown-nibbed 0.5 mm pen. If this text were used in an ISO-sized document (e.g. A0), and the document were reproduced at half its original size (A1), the text would be rendered 3.5 mm high with a stroke thickness of 0.35 mm—the yellow-nib size. Thus, changes to reductions or enlargements can be made easily as everything is in proportion. This worldwide standard (excepting Canada and the United States) ensures that drawings can always be legible even after microfilming, photocopying, and faxing.
The main drafting sets of four nibs came in two kinds: Gold and Silver. The Silver was for rough tracing paper, and the Gold was for plastic film (velograph or durables). Drawing boards changed as a result of technical pens—a hard (not spongy) surface was required, and when plastic film was used, the static attraction between plastic cursors, T-squares, set-squares etc. meant that as one lifted the edge from the film, the film would rise through static
attraction and the ink would blot. The solution was to stick down a plastic
sheet (Osalid) that attracted the film more strongly than the drafting instruments. The tracing paper
or velograph sheet would be placed on the Osalid sheet stuck onto the drawing board and the air brushed away. Brushing charged the surface, and the film would then be taped taut (but released at the end of each working day to allow for overnight temperature expansions and contractions).
When pen plotters became widespread, a special variety of point assemblies was produced. These had the basic characteristics of the standard pen nib, but the tube was much thicker to strengthen it against quick lateral movements. Only the tip of the tube had the desired, line-size width. They fell out of use as plotters were replaced with ink-jet printers.
While the Rapidograph style of pen is still widely used by artists, the use of computer-aided design (CAD) has largely replaced the need for manual drafting
. Also, the development of felt-tip, allegedly pigment-ink-based pens have provided cheaper, lower-maintenance disposable tools that sell much better than traditional technical pens. In general, the development of technical pens has evolved through a gradual sacrifice of line and ink quality in favor of ease of maintenance and use.
s are used to make consistent marks on the paper. A technical pen can be attached to a pair of compasses to produce circles.
Engineer
An engineer is a professional practitioner of engineering, concerned with applying scientific knowledge, mathematics and ingenuity to develop solutions for technical problems. Engineers design materials, structures, machines and systems while considering the limitations imposed by practicality,...
, architect
Architect
An architect is a person trained in the planning, design and oversight of the construction of buildings. To practice architecture means to offer or render services in connection with the design and construction of a building, or group of buildings and the space within the site surrounding the...
, or drafter to make lines of constant width for architectural
Architectural drawing
An architectural drawing or architect's drawing is a technical drawing of a building that falls within the definition of architecture...
, engineering
Engineering drawing
An engineering drawing, a type of technical drawing, is used to fully and clearly define requirements for engineered items.Engineering drawing produces engineering drawings . More than just the drawing of pictures, it is also a language—a graphical language that communicates ideas and information...
, or technical drawing
Technical drawing
Technical drawing, also known as drafting or draughting, is the act and discipline of composing plans that visually communicate how something functions or has to be constructed.Drafting is the language of industry....
s. It has been also generally called "rapidograph", although that particular name is officially a trademarked line of products made by German company Rotring
Rotring
Rotring is a German technical writing and drawing instruments company based in Hamburg.-History:The company was established in 1928 as Tintenkuli Handels GmbH. The company's first product was the Tintenkuli, a stylographic pen—a fountain pen with a narrow steel tube instead of a conventional nib...
, and by American manufacturer Chartpak, Inc. when they purchased the rights from Rotring to produce the pens in the USA under the Koh-I-Noor brand.
Most technical pens use ink cartridges which can be refilled or replaced.
History
Early technical pens (ruling penRuling pen
A ruling pen is a vintage drawing instrument for drawing with ink or with other drawing fluids.A ruling pen contains ink in a slot between two flexible metal jaws, which are tapered to a point. It enables precise rendering of the thinnest lines. The line width can be adjusted by an adjustment screw...
s) consisted of a small pair of calipers, having one flat and one bowed leg holding ink between them. By adjusting the gap between the legs the width of the line drawn by the pen could be adjusted. Such pens, kept at a constant angle to the paper, were used for ruling lines, but not for cursive
Cursive
Cursive, also known as joined-up writing, joint writing, or running writing, is any style of handwriting in which the symbols of the language are written in a simplified and/or flowing manner, generally for the purpose of making writing easier or faster...
handwriting, nor for off-hand flourishes. The Graphos technical pen introduced in 1934 miniaturized the caliper principle and made the points easily interchangeable.The Sheaffer company produced an expensive drafting set which included such pens for use on linen
Linen
Linen is a textile made from the fibers of the flax plant, Linum usitatissimum. Linen is labor-intensive to manufacture, but when it is made into garments, it is valued for its exceptional coolness and freshness in hot weather....
prints. These sets were often presented to a draftsperson upon becoming 'time served', which is marking the end of the apprenticeship.
Fountain pen versions
In the 1950s, fountain pens with cylindrical points became available, but they were complex instruments with tubes holding a tiny shaft. To release ink the shaft is depressed and a line of about the width of the exterior diameter of the tube can be drawn. Additionally, in later models, the tube had a small ledge that effectively narrowed its end, that - while maintaining the line thickness - made the tube thicker along most of its length and also protected ink from spilling while drawing along the edge of a rule, set-square, T-squareT-square
A T-square is a technical drawing instrument used by draftsmen primarily as a guide for drawing horizontal lines on a drafting table. It may also guide a triangle to draw vertical or diagonal lines. Its name comes from the general shape of the instrument where the horizontal member of the T slides...
or other template (the ink had no immediate contact with the template's edge). Some special, more expensive nibs were equipped with tubes made of tungsten or with their tips made of synthetic precious stones, to slow their wear on hard surfaces.
Ink tubes
In the 1960s, the pen's design evolved to feature tubes of ink that were filled with an eyedropper or from a narrow spout on a special bottle of inkInk
Ink is a liquid or paste that contains pigments and/or dyes and is used to color a surface to produce an image, text, or design. Ink is used for drawing and/or writing with a pen, brush, or quill...
. Such pens frequently came in sets of various sizes, and several pen points which were installed into the holders that also contained a filled fountain, which in turn would be screwed into a handle. The construction and amount of parts varied depending on the company, and the parts were not cross-compatible in most cases. Some later designs (like the Staedtler MarsMatic700) had especially designed channels to allow better air flow in between the wall of the external grip and the point assembly. This made ink flow more reliable. The general drawback of this group of pens is that they have to be frequently and carefully cleaned to remove all ink from the tubing, otherwise it would set and could not be removed.
Brands
In the United States, several firms produced this kind of technical pen: WRICO, Leroy, and Koh-I-Noor. Each had its own proprietary sequence of line widths, meaning that the widths were not standardized across the industry, and each company's specifications for the widths did not match the others. And the specifications were given as fractions of an inch instead of fractions of a meter. In the case of technical pens made for the US market, they were marked with both proprietary symbolic expressions (4×0, 3×0, 2×0, 0, 1, 2 etc.) and standard metric dimensions denominated in millimetres.For the rest of the world, the most recognized brands were Staedtler, Rotring and Faber-Castell; currently only Koh-I-Noor USA, Rotring, Rystor and Staedtler still make the traditional technical pen.
Technical information
A full set of pens would have the following nib sizes: 0.13, 0.18, 0.25, 0.35, 0.5, 0.7, 1.0, 1.5, and 2.0 mm. However, the International Organization for StandardizationInternational Organization for Standardization
The International Organization for Standardization , widely known as ISO, is an international standard-setting body composed of representatives from various national standards organizations. Founded on February 23, 1947, the organization promulgates worldwide proprietary, industrial and commercial...
(ISO) called for four pen widths and set a colour code for each: 0.25 (white), 0.35 (yellow), 0.5 (brown), 0.7 (blue); these nibs produced lines that related to various text character heights and the ISO paper sizes.
Text (produced by an ISO stencil
Stencil
A stencil is a thin sheet of material, such as paper, plastic, or metal, with letters or a design cut from it, used to produce the letters or design on an underlying surface by applying pigment through the cut-out holes in the material. The key advantage of a stencil is that it can be reused to...
template for use with the technical pens) of 5 mm in height has a stroke or line thickness of 0.5 mm, and so requires a brown-nibbed 0.5 mm pen. If this text were used in an ISO-sized document (e.g. A0), and the document were reproduced at half its original size (A1), the text would be rendered 3.5 mm high with a stroke thickness of 0.35 mm—the yellow-nib size. Thus, changes to reductions or enlargements can be made easily as everything is in proportion. This worldwide standard (excepting Canada and the United States) ensures that drawings can always be legible even after microfilming, photocopying, and faxing.
The main drafting sets of four nibs came in two kinds: Gold and Silver. The Silver was for rough tracing paper, and the Gold was for plastic film (velograph or durables). Drawing boards changed as a result of technical pens—a hard (not spongy) surface was required, and when plastic film was used, the static attraction between plastic cursors, T-squares, set-squares etc. meant that as one lifted the edge from the film, the film would rise through static
Static
Static has several meanings:* Static electricity, a net charge of an object** The triboelectric effect, e.g. from shoes rubbing carpet* White noise, a random signal with a flat power spectral density** Noise , a type of radio interference...
attraction and the ink would blot. The solution was to stick down a plastic
Plastic
A plastic material is any of a wide range of synthetic or semi-synthetic organic solids used in the manufacture of industrial products. Plastics are typically polymers of high molecular mass, and may contain other substances to improve performance and/or reduce production costs...
sheet (Osalid) that attracted the film more strongly than the drafting instruments. The tracing paper
Tracing paper
Tracing paper is a type of translucent paper. It is made by immersing uncut and unloaded paper of good quality in sulphuric acid for a few seconds. The acid converts some of the cellulose into amyloid form having a gelatinous and impermeable character. When the treated paper is thoroughly washed...
or velograph sheet would be placed on the Osalid sheet stuck onto the drawing board and the air brushed away. Brushing charged the surface, and the film would then be taped taut (but released at the end of each working day to allow for overnight temperature expansions and contractions).
When pen plotters became widespread, a special variety of point assemblies was produced. These had the basic characteristics of the standard pen nib, but the tube was much thicker to strengthen it against quick lateral movements. Only the tip of the tube had the desired, line-size width. They fell out of use as plotters were replaced with ink-jet printers.
While the Rapidograph style of pen is still widely used by artists, the use of computer-aided design (CAD) has largely replaced the need for manual drafting
Technical drawing
Technical drawing, also known as drafting or draughting, is the act and discipline of composing plans that visually communicate how something functions or has to be constructed.Drafting is the language of industry....
. Also, the development of felt-tip, allegedly pigment-ink-based pens have provided cheaper, lower-maintenance disposable tools that sell much better than traditional technical pens. In general, the development of technical pens has evolved through a gradual sacrifice of line and ink quality in favor of ease of maintenance and use.
Related technologies
Drawing board instruments, such as set squares, shape templates, text stencils and French curveFrench curve
A French curve is a template made out of metal, wood or plastic composed of many different curves. It is used in manual drafting to draw smooth curves of varying radii....
s are used to make consistent marks on the paper. A technical pen can be attached to a pair of compasses to produce circles.