Samuel Kummrow, Team Leader New Technologies & Testing, is known for his enduring love affair with non-motorised two wheelers. Ever since childhood, there has been one idea at the back of his mind: “I’d love to build a bike from scratch myself one day!”
As I chat to Sam about his passion, that good old Swiss song, “Mir sind mit em Velo da” (We’ve come by bike) inevitably springs to mind! Sam is always out and about on a bike, and he recently became the proud creator of a bike brand all of his own.
All beginnings are difficult
Back in April 2008, Sam was one of the first engineering trainees at Pilatus. He gained an insight into various areas of work and learned a lot about manufacturing and processing metal. In 2017, there was an opportunity to set up a workbench in the warehouse of a bike store in Kägiswil. Sam bought professional welding equipment and a stack of scrap iron to practise on. “I spent two years welding a metre-long seam every week, only to throw it in the bin afterwards. I welded raised beds for the garden and made birds out of scrap steel”, he tells me.
Next, he got hold of scrap bike tubes from a bike frame builder in Zurich. He persevered in his attempts to mitre them at different angles, welding them together to form “exhausts”. “The tubes mostly ended up with holes in them after my machining, so I was disappointed. At that point, I was ready to abandon my project of building a bike myself. But after further exchanges with professional frame builders, watching various YouTube tutorials and even more practise, it suddenly clicked!”, Sam tells me.
A bike is born
Sam entrusts the task of drawing the bikes to a good friend who is equally enthusiastic about two-wheelers. He then cuts and grinds the special thin-walled tubes to size and places them in a special frame jig which is first aligned and adjusted to the model with a simple laser and spirit level. The ultra-thin tubes have to be mitred very precisely and without tension, which calls for a lot of patience and a delicate touch with the hand file. Making his first frame, Sam found out the hard way that you can’t finish welding it completely while still in the jig: He couldn’t get it out again due to deformation caused by the welding! “I was never good at listening and thought I knew better than the frame builders, who had warned me about the problem”, he laughs. So the final welding of the bike frame is done on the workbench. It’s important to weld in the right order and to keep the temperature under control so that anything that is deformed by the heat subsequently returns to its original form. The surface is then treated by an external company.
After painting, the frame returns to the workbench for recutting of bearing seats and threads, and removal of excess paint. Last but not least, all the other parts are connected to the frame to complete the finished product.
Bike versus aircraft
The value creation chain during bike building is somewhat similar to certain aspects of producing Pilatus aircraft. If you want to build and sell bikes, you have to be a designer, engineer, buyer, metrologist, jig builder, welder, mechanic and dealer all at once. As a Team Leader of the New Technologies and Testing department, Sam was heavily involved in developing the PC-24. He and his team now perform mainly structural tests on PC-24 components at the “Sustenhorn” Test Centre. “Building bikes is fantastic training for me! I sincerely believe it’s made me a more complete engineer”, he comments.
The sustainable bike from Central Switzerland
Sam has built eight bike frames so far. Now that he has all the parts in stock and has made a careful note of the working method, it takes him 30 hours to put together a hardtail bike frame a mountain bike with front suspension only. As a test, Sam took part in the Swiss Enduro Series in Laax where he put one of his self-built bikes through its paces and came fourth. “I have to admit I was pretty proud when the speaker at the event asked me what kind of nice hardtail I was sitting on”, he tells me. After the race, Sam discovered a small crack which he repaired with a reinforcement. His bike frames are all made of steel, which is a very good-natured material that is relatively easy for a layman to work with. Steel bikes are the most sustainable in terms of their environmental footprint, and even more so if produced locally. Switzerland also offers a huge number of small and medium-sized enterprises interested in this sort of project. In Sam’s case, small local firms take care of engraving work, surface treatments and production of milled parts.
The TJN – “Truisch ja nid” – model
A Swiss-German brand name for a product made in Central Switzerland would be a good fit, or should it be English after all? One day at the bike store, Sam was chatting to a customer who asked him when he’d finally be finished with the “Gländer” – that’s how folks from Central Switzerland refer to stair railings. And since the bike tubes look a bit like stair railings – that’s how the brand name came about.
The first model was named “TJN”. “When I was working on the frame I was super nervous about cutting the expensive special tubing; I measured, re-measured and measured again before the first cut”, laughs Sam. At some point, his designer friend remarked on Sam’s obvious lack of confidence – “You do not dare!” – and that became the name of the first model. The other models were called Wichelsee, Lopper and Mueterschwandenberg.
From engineer to craftsman
For Sam, all the welding, polishing and filing makes a refreshing change to his everyday work. “I enjoy leaving my engineer’s hat at work and putting on my craftsman’s hat at home”, he says. But he wants the bike building to remain a hobby, which is why he doesn’t get involved in any marketing. He’s currently working on a full-suspension mountain bike and may add a fat bike later. “But it’ll be a while before that happens. After all, I need time to ride myself!”, he grins.
