Introduction

The Baskerville font was designed by John Baskerville an eighteenth-century Birmingham printer who considered all aspect of the printing process, from the design of the thick and thin strokes of each letter which assisted in the legibility of the character, to creating the letter face on the three dimensional punch tool, to the type setting and quality of the ink that transferred the letter to the page.

While there are many eighteenth-century books containing Baskerville’s font, the books represent the final accumulative stage in the journey of craftsmanship that created those books. It is the transformative journey of craftsmanship, the material aspect of the punches manufacture, which this exposition will focus on. 

Baskerville’s workshop has not survived nor have any documentation with regard to his workshop practices. Therefore his punches are the primary source of evidence connecting Baskerville to his craftsmanship.

This exposition presents an interdisciplinary approach to investigating the punches utilising a combination of digital technology investigated through the lens of craftsmanship to interpret and reveal the hidden processes of craft embedded within these punches.

The punches are owned by Cambridge University Press and housed in the Historical Printing Room at the University Library Cambridge. The collection consist of approximately 2750 punches according to the records made at the time when the punches were donated to Cambridge in 1953.

This pilot study was supported by History West Midlands with a grant of £12,000. The project was a collaboration between the Centre for Printing History and Culture, Centre for Digital Design and Manufacture at the School of Jewellery, Digital Content Unit Cambridge University and the Birmingham Assay Office. Importantly the collaboration brought together a range of disciplines each with their own underpinning subject expertise and methodological approach. Collectively this provided an original methodology to allow for the visual, physical and material analysis of the punches.  The progress of this cross-disciplinary research was captured in a short film ‘The lasting legacy of Birmingham’s famous printer’ made by ICE Productions. 

For the purposes of this exploratory study and for means of comparison, the single letter form of the lower case g was selected in the ten largest point sizes of the Baskerville font from 14 - 60 to optimise the digital technologies deployed in the project. The sampling represents a fine example of the distinct thick and thin weighting of the strokes, a recognisable characteristic of the Baskerville font. The ‘face‘(image on the left) of the punch has always drawn the eye as the final process of punch cutting and the height of craftsmanship, it is also the most easily understood aspect of the punch. The shank (image on the right) in contrast has often been overlooked disregarded due to its rough and raw finish, however these surfaces have been left and bear witness to the marks of manufacture - witness marks. Could deciphering these marks provide valuable clues to the skills, level of technology and material understanding required for their manufacture?

 Evidence of workshop manufacture

The largest punch was selected in order to maximise the data collected, visual inspection by eye with the aid of a jewellers loupe provided a first appraisal to ‘scope’ the punch, and later on digitally through 3D laser scanning and reflectance transformation imaging (RTI).

In the process of visual assessment via the loupe, the handling of the 3D punch conveyed the tactile, haptic and physical weighting through the hand, presenting an opportunity to engage with the punches as the crafts people who forged, cut and made the matrix impressions would have done. The punch was a process of craftsmanship and one of many tools critical to the production of a book, the craftsmanship of the punch can reveal significant insights on its manufacture. Although the face of the punch varies considerably due to the point size, the shank of the punch is reasonably consistant. Determined by a human scale the length required to securely hold the iron bar in tonges and jigs as it is being crafted (forged, cut and polished) and by hand for its application as a tool (hammered into the matrix).

A punch would have started life as an iron bar, a punch template, sized by the forge to the requirements of the printer. The 60 point punch demonstrates significant forging in its tapered shape from a widening of the face end rectangular in profile to the narrowing of the hammer end square in profile. Tool steel can be transformed by tempering from a malleable material to hard material required for tools, a sought-after specialist iron alloy demanded a higher price, efficiency of material use would have been an integral aspect in the crafting of the punches. The face end of the tool would have gone through a process of ‘upsetting’ where the end of the shack was hammered down and the malleable metal spread horizontally at that point to accommodate the size of the letter, indents possibly from blacksmithing tongs or a straight edged jig are evident on the short side of the punch shank illustrating the buldging of the metal as it was held secure.

Witness marks graduate along the length of the shank from raw and uneven at the hammer end becoming more refined with parallel file marks polished out closer to the face. The shank presents finishes that were never intended to be seen beyond the printer workshop while the face of the punch was the working end which required a high finish. Although the face has always drawn attention looking beyond the face can reveal much about its hidden craftsmanship. Understanding the craftsmanship of the punch is important as the punch is the first metal tool and fundamental to a series of downstream metal skills that transfed the letter onto the page.

Creating the letter face on the punch requires the selective removal of material from the forged punch template. When creating the face the letter form has to be supported while the negative space within and around the letter form is removed, the material supporting the letter are known as the shoulders of the punch. The shoulders taper from the surface of the shank towards the edge of the letter form, the greater the negative space the deeper into the punch sides the taper is cut and the longer the length of the taper. On the 60 point lower case g punch the beginning of the taper starts half way down the shank creating a gradual taper that will support the letter design, while at the same time allowing the force of the hammer strike to travel directly along the shank and evenly spread into the shoulders when it is used as a tool to make the impression in the copper matrix.

The length and angle of the taper are also important to the maintenance of the tool. As a tool it will be subject to the wear-and-tear of use, with the sharp clarity of the face exposed to multiple metal to metal contacts.  A longer length of taper allows a smaller angle between taper and face therefor the face can be refinished several times to keep the edges crisp with minimal impact on the letter form.

Punch cutting is a highly skilled technique and each punch cutter brings their own approach, it is the marks left by hand behind the face of the punch that in isolation are unremarkable but collectively begin to reveal the sequence of craft skills and the decision making that those crafts people made in creating the punch.

The letter punch lower case g illustrates the shoulders with various angles of taper dictated by the letter form and how much material was removed. On the shoulders finer witness marks of manufacture are evident, parallel linear indentations left by the action of a file being draw across the surface which fade out towards the face, polished out to provide a consistent surface as the shoulders meet the face.

In sharp contrast to the shank, the consistency in the level and finish of the face surface is distinct, the process of crafting the punch was ultimately to achieve this final finish. This surface would be replicated multiple times in matrix moulds, although a this surface attracts much attention it is a surface that provides little evidence of witness marks.

Looking closely at the shoulders there is evidence of a fracture in the metal of the middle shoulder (image right). When the punch is being made the metal is malleable, the process of tempering transforms the punch into a tool which achieves the required hardness but can be brittle. Tempering utilises the intense heat of a hearth to transform  the punch, visually gauged by the craftsperson as a rainbow of oxide colours develope along the punch indicating the tempering point. The results of tempering are evident in the application of the punch as a tool and sometimes in a subtle colour change in the metals surface. Tempering is a thermal process and often difficult to detect - a hidden aspect of craftsmanship.

Observations on the condition and fracture in the punch prompted further questions on the craftsmanship and application of the punch as tool: Was the fracture a fault in the bar? Was it revealed when the shoulders were cut? Did the tempering process open up the fracture? Was it fractures due to wear-and-tear? Could the punch still be used?

Data Collection

Laser scanning is a non-invasive process were the object is held in a jig and the articulated arm moves around the artefact to capture scans from various perspectives. Using 3 points of physical reference on the artefact as points of registration, the software stitches the digital scans together to create a virtual point cloud of data. As such a digital skin of the high and low points representing the topology of the surface and accurately capturing the size, scale and texture of the punch. The digital skin data once cleaned and converted provided the virtual data for a 3D printed file around which the supports could be placed for downstream activities in translating the virtual into the tangible. 

The jig in this instance was a pair of long tongs coated in a rubber, this prevented metal to metal contact (which would not be appropriate for a historic artefact) and provided various degrees of tension to grip the different punch sizes.

An interesting observation was made while the punch was in the jig. From certain angles when scanning the punch face appeared to have blue marks on the surface, ink would not have been applied to the surface of master punches as the only surfaces the punch came into contact with was when it struck the copper of the matrix metal.  However there is one process that could result in a blue sheen on the metal surface, blue is one of the rainbow of colours that are created as an oxide in tempering. One of the characteristics of Baskerville font is the contrast created by the thick and thin letter strokes, from a metals perspective the iron punch acts as heat sink however the thick and thin aspect of the letters design create dissimilar heat sinks across the varying masses of metal, making the control of the tempering process very difficult. While some areas of the letter face will have achieved temper others may not, presenting an inconsistent oxide on the surface. Further analysis and comparison are required to fully explain this observation. 

Data Analysis and Interpretation

Once all the laser scans are registered to each other a virtual wire frame of the object can be built and rendered (image left), this is a digital output of data to which numerical data can be extracted to aid in analysis of the punches in design, scale and potential consistency of craftsmanship approach. 

A primary aim of this project was the integration of multiple methods of data collection which in combination would provide an original methodology with cross disciplinary outputs.

Image on the right utilises Reflective Transformation Imaging (RTI) a specialist photographic method used by the Digital Content Unit Cambridge University, which uses multiple images of the same object to create textured images of the punch face. The light grey represents the original 60 point punch, the red outline a modern digital version. The ability to overlay one data set with another provides useful comparative analysis. The modern strokes are notably thicker in areas and have lost some of the distinct character and movement of the original.

These punches are the closest evidence to Baskerville’s original design intent for his font.

Digital Output

3D printing is an additive process the complete opposite of the traditional manufacture used in the original punches.

The are two aspects to the physical 3D printing process, the building of the object itself, and the support structure that enables the object to be printed as it grows, without a support structure the print might fall over if top heavy or miss-register on the 3D printing platform.

A number of 3D printing test builds were undertaken to identify the most suitable supports. Image to the left illustrates support pillars on the base and along the side of the punch. When deciding which structure to use the access to and selective removal of supports is important so as not to leave modern 3D printing witness marks on the reconstructions. The base supports were the least invasive and did not interfere with the surface texture on the sides of the punches.

The 3D prints are tangible digital outputs, they can also be stepping off point for downstream activities. The 3D prints can be sacrificial masters for metal casting to allow haptic engagement, conveying the material weight and balance of the punch as well as scale and design.

In conclusion, this short exposition which articulates the practice-based research leading from the application of craft practice philosophy and material intelligence to provide new perspectives within interdisciplinary settings has detailed the testing and efficacy of the digital data collection methods in this case study. More research is required to fully understand the craftsmanship of these punches and a larger project is planned that will combine a number of methodological approached that will extend and improve our understanding of these punches.