Renzo Jansema is
not your average thesis student
in order toMake thingsthat last
It started with a pen.
I made my first one
as a teenager, and
never stopped.
Self-taught on wood and metal lathes, one broken thread at a time. Nine years later, collectors pay up to €3,000 for a pen, and a Japanese industrial group commissioned one for its retiring CEO. This is how they get made.
I collect rare woods, burls and ebonite, and let the combinations decide what the pen becomes. A burl grows where a tree was hurt. Its grain is wild, soft and impossible to repeat.
Grip first: thickness, length, shape. Everything else balances around it. The ratio between body and cap makes or breaks a pen. Mine run a little larger than most, because they’re more comfortable.
Most burls are too soft to machine. Under vacuum and pressure I fill them with resin, so the wood keeps its grain but gets the hardness to hold a thread. Once it’s stabilised, it lasts forever.
The threads don’t live in the wood. I turn and thread ebonite sleeves and set them inside the body. Ebonite is vulcanised rubber: warmer than plastic, tougher than wood.
The hardest part, and where most pens broke. Inner and outer threads in ebonite with walls of one millimetre or less. It took years of trial and error to get a machining flow that doesn’t tear the wall out.
Where your fingers sit and the nib goes in. Bodies, caps, threads and sections are all mine. I buy only what a specialist does better: nibs and feeds from JoWo, and the filling systems.
Metal rings and inlays go in before the final shaping. Wood, ebonite and metal are then turned together, so every line runs straight through from one material into the next.
Sanding, polishing, then writing with it. Every pen is made once. Collectors buy them because nothing else on the market is like them, and because wood feels warm in the hand in a way metal and plastic never will.
Nine sides. Stabilised ebony. Fully sleeved in ebonite.
A pen for Nippon Sanso’s retiring CEO, with complete creative freedom. Faceting a round object nine times, by hand, with walls this thin, wasn’t possible with my existing tools. So I designed my own faceting jig and work holding, and a milling process for ebonite too thin to machine the normal way.
It took about three months, mostly design iteration, and I rebuilt my workflow to fit the Aalto workshops. The 14K gold nib is engraved with the company logo.
Then I learned
why it works.
The lathe taught me how to make things. Three degrees taught me how people use them, why they hold together and what they mean.
IpsumStudio, self-taught
The obsession.
Wood and metal lathes, a lot of broken pens, and the stubbornness to get a thread into a one-millimetre wall.
TU Eindhoven, Honours · Georgia Tech exchange, 4.0 GPA
How people use things.
User research, form and prototyping. As lead design engineer of TreeD I learned to lead designers, architects and engineers, and we built our own paste 3D printer.
TU Eindhoven
Why things hold together.
Mechanics, materials and tolerances: the maths behind what I’d been doing by feel. In parallel, soft-robotics research that won Best Demo at the Dutch Soft Robotics Symposium.
Aalto University, Helsinki
What objects mean.
One of the world’s leading design schools. Material culture, value and meaning. Here I made the Nippon Sanso pen and Meloen, and co-founded Rabbithole in the Aalto Founder Sprint.
With your pen company
All of it, in one object.
Six months from January 2027: craft, engineering and design research, pointed at your products. See the set-up →
Four things I bring, and the projects that prove them. Pick one.
Pens, products, materials, soft robots and a startup.
Choose a word to light up the projects behind it.
Curious. High-energy.
Happiest with
sawdust on my hands.
I need people around me, and I like a team that challenges each other to get better. I challenge, and I want to be challenged back.
A listener first, a clear communicator and a motivator. And we should have fun doing it.
I moved alone to a new country two days after a motocross accident left me unable to walk for months.
Oboe (Texas regionals and area auditions), saxophone in a Texas marching band, piano, motocross, sailing, skiing, calisthenics.
Six months, starting January 2027. An industry collaboration for my MA in Contemporary Design at Aalto University, with academic supervision from Aalto. You don’t need a topic ready. We shape the question together.
How can material and construction choices create a fountain pen that becomes more valued through years of use?
Directions: material ageing & repair, ergonomics & writing feel, AI-assisted bespoke craft.
Because I already think like one. I know a pen from the inside: material, threads, section, balance, and how it ages. Nine years of making, three degrees of rigour, and the energy to build the thing, not just describe it. Willing to relocate to wherever your pens are made.
