Hamburg, Germany | Pen Production
Only by understanding the craftsmanship and time involved in producing this collection of Pens can you begin to truly appreciate the beauty of the Ebonite collection.
In 2018 we began searching for an Ebonite manufacturer who was not only willing to work with us but who shared our values for openness, quality and craftsmanship. This proved a challenge but we eventually located an incredible factory nestled on the banks of the Elbe river near Hamburg in Germany who produced the most exquisite and colourful Ebonite using traditional processes. After some initial tests in 2018, we decided to go ahead to produce our first collection which we launched in late 2019.
During the production of our bars, we made a visit to Germany to oversee the production and learn more about the unique process behind this beautiful material. We had the honour of being shown around the factory by the inspirational entrepreneur Mrs Meike Huijssen who brought Ebonite production back to Germany just over 10 years ago. Below is a little more information about the process so you can appreciate the beauty and story behind the new collection.
Ebonite is an organic polymer, commonly known as “hard rubber” or vulcanised rubber and is produced by combining high-grade latex with sulphur and linseed oil. There are still many technical and industrial uses for Ebonite, however, what we want to share with you is in reference to the beautiful hand made material that we work with to produce our Pens.
The Ebonite is produced by the combination of two core ingredients: natural rubber latex and sulphur. The mixture of materials passes through multiple production stages before it becomes the ebonite material that we can machine.
The best way to describe the process is that of a kind of baking bread, taking flour, making dough and baking as at every step measurements, temperate and time are critical to ensure a perfect result. The process to produce Ebonite takes a similar form; time-intensive, technical and requires a tacit knowledge that only years of experience can give you.
Ebonite is a unique material with a range of features unmatched by modern alternatives. It is durable, light, grippy (even when polished) and warm to the touch, making it a perfect material for a Pen. There is something extremely timeless about Ebonite which is extremely hard to describe and can’t be easily translated through photographs.
Unlike modern mass-produced materials, Ebonite is unpredictable. The variation of colours and patterns makes each Pen extremely special as each Pen in the collection is completely unique and individual. No two pens will ever be the same.
It’s true to say that working this way takes more time and skill, but this is what we crave and is the difference between forgettable and timeless.
How our Ebonite Pens are made
- The process begins with caoutchouc-tree (rubber trees), where the tear is harvested and collected.
- The caoutchouc (natural non-vulcanised rubber) is washed and then dried in sheets.
- Caoutchouc of the highest quality (crepe no. 1) is separated and selected. Our factory only uses Crepe no.1 sourced from sustainable forests.
- A rubber compound is made by mixing the Crepe No. 1 Caoutchouc with Sulphur and linseed oil. This rubber compound is floppy and elastic akin to a rubber ball or eraser, and is cut into sheets.
- The rubber compound is layered on trays which are stacked onto a rack.
- The compound is then loaded into a large autoclave (special pressured oven)
- Vulcanisation - The compound is placed under pressure and slowly warmed to a specific temperature until the vulcanisation reaction happens.
- The now vulcanised rubber is slowly cooled over 24 hours. This is a slow process as our factory uses traditional techniques that don’t include additives that speed up the process but result in an inferior product.
- The vulcanised rubber ‘plates’ are removed from the autoclave. The vulcanization has transformed the light yellow compound into a rigid, hard and shiny sheet with a black almost burnt appearance.
- The plates are firstly shredded using a mechanical cutter.
- Once shredded the material is then ground into particles
- The dust particles are then filtered into various grades 100μm/120μm/140μm
- The course grades are removed for industrial use
- This fine dust is Ebonite dust and is reintroduced into the process again.
- Fresh Crepe No.1 Caoutchouc compound is mixed with Ebonite dust and linseed oil which results in a Black ebonite compound
- The compound is then extruded through a press with/without colouring to produce rods.
- The soft rods are inserted into high-grade steel and depending on the diameter vulcanized between one and three days in the autoclave.
- Once the vulcanised rods are removed from the autoclave they are tested for a hardness > 82 D shore
- The Rods are then ground to remove the external impurities before receiving a mechanical polished and sorted into colours and grades.
- The rods are prepared for our order and ground again to our specified diameter
- On receiving the rods we check each rod and then prepare them for use on our lathers.
- The rods are then machining into Pen components using high CNC technology by our specialist in the UK.
- We receive the machined components at our workshop in our Manchester studio. The parts are checked and cleaned to remove cutting fluids.
- Once cleaned we sand the components using grades abrasive paper from 240g to 7000g.
- Once sanded they are checked again and then are polished using polishing mops and compound until they have a glossy mirror finish.
- Once the parts have been polished they re-checked and finally cleaned.
- Once they are cleaned we assemble and check each Pen before packaging.
We would like to say a big thank you to Mieke and the team at Schönberger Ebonite Manufaktur for their time and openness in sharing their story.