A newbie approach to the art of frame building
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A newbie approach to the art of frame building:
Crafting a Steel Mountain Bike Frame
INTRO
2023 was my third year living in Germany, and Ralf a colleague of mine. Even though we worked in different fields, the passion for DIYing, extreme sports and bikes, brought us together quite soon.
One day, I remember he made a post on Instagram offering his workshop and – most important – his knowledge, to anyone interested in building his very own bike.
I knew immediately that was a great opportunity, but I can’t lie when I say at first I was quite hesitant: I knew literally nothing of frame building and my building skills were basic; I already had experimented with wood in my life, but never had the chance with metal.
To complicate it even more, at the time I owned a motorcycle, which I loved, but that was my only mean to get around; how could I carry all the bits and pieces to the workshop every time? Lastly, the time factor: how long is this going to take? This definitively didn’t seem like a two weekends side-job.
There was no way I could make this happen.
A quick chat with Ralf at the coffee machine was enough to reassure me. Luckly Oliver, another friend of mine, accepted Ralf’s offer and from early January we started spending our weekends in Bischofsgrün.
The game was on.
THE VISION
When asked how I imagined my kind of bike, I knew I wasn’t aspiring to an aggressive geometry. Since the beginning, I liked much more the idea of an all-mountain frame which could accommodate enough bags and bottles to use it not just on trails, but for some bikepacking trips as well.
On top of that, I’ve always been fascinated by bike touring and I’ve done my fair bit of travels over Europe. When I started, there was one bike that was rocking over the competition and, at least for me, was the touring bike for definition: the Cinelli Hobootleg. A steel framed bike so strong yet so simple, it could be repaired anywhere in the world.
Cinelli Hobooleg (Courtesy of Cicli Servadei)
This frame, and what it represents, had to be the inspiration for what I wanted to create. With this in mind, I decided to go with a more relaxed geometry and opted for more space on the frame’s inside triangle.
THE BUILD
After a rough sketch of the project, we soon started with the bottom bracket, the first piece of the build. This is when Ralf introduced us to brazing: a classic welding technique used by frame builders, where a metal-to-metal joint is welded by filling the gap with some bronze melted by a torch.
With some trial and error, I managed to stick the three pieces of steel together. It felt like a massive accomplishment and I was so proud!
We perfected the bike geometry using BikeCAD, a software where I could input every parameter and minimize mistakes with the real-life material.
With a clear plan in mind, we ordered top tube, down tube and seat tube made from Columbus steel and we started fitting them to measure.
Talking about tools, one of the most important I got to use in the workshop, is the bike jig. Basically a big clamp where loose tubes can be locked in place and the geometry of the bike can be dialed with precision. I can say with confidence that Ralf owns the Ferrari of jigs, it’s called “Anvil” and it was a crucial aspect for making our lifes easier during the process.
Checking the bike’s geometry with the tubes locked in the Anvil
Top, down and seat tube - Cleaning 10 freshly brazed
bottle bosses inside my WG’s bathtub
By brazing, filing, sanding and grinding over and over, we got used to the process and went slightly faster. Ralf was always looking on top of us to avoid any major screw up, and helping us when needed.
Over the span of 4 months we worked during weekends and the frame was finally taking form. By connecting chainstays and seatstays to the droputs, the frame was complete. Something I learnt quite soon is that you could go on endlessly with the finishing touches, as it seems there’s always something new to refine and sometimes it’s better to accept the compromises than overwork too much.
Brazing
Now having the welded frames, Oliver and I got them professionally sandblasted and painted.
Of course I had to homage the Hobootleg initial inspiration. For this reason, I decided to go with a mild desert color, which fitted the bike perfectly.
From frame-builders, our job finally switched to bike mechanics.
Over the 5 months working on the frame, I had gathered from the second-hand market all the bits and pieces to complete the bike and I couldn’t wait to fit them on!
For all the bike-savvy ones here’s a list of what I used:
Groupset: Shimano Deore 1x12
Wheels: Orbea 29”
Tires: Maxxis Ikon
Fork: Rock Shox Judy
Headset: Chris King
Handlebar: Raceface Turbine
Grips: ESI
Brakes: Magura MT-4
Dropper post: LaPierre
Pedals: Magped
Saddle: Fizik
I’m not going to lie, assembling the parts and navigating every single standard in the bike parts industry was a real pain, but the reward was priceless: the bike was finally complete!
I remember going on trail for the first time: I was overthinking a bit and asking myself if the welds I made could handle the stress and vibrations. As I took my first ride and the wheels started rolling, I felt a deep sense of accomplishment. It was a culmination of hard work, dedication, and love for the craft.
Needless to say, the bike handled it like a charm.
The bike was ready to rock, and we surely put it good use throughout the summer.
A happy face and a complete frame
Taking the frame to be sandblasted
First time on trail
WHAT’S NEXT
The most trained eyes maybe already spotted an enormous amount of bottle bosses brazed in the inside triangle. Well, that was planned.
As said before, the initial vision was to build a bike capable of handling trails and bikepacking trips. The frame was custom-made for my riding style, so I loved the idea of adding a custom-made bag as well. My girlfriend Benni came to help for this step.
We first took the measurements of the inner triangle on a piece of cardboard, and then drew some mock-ups. The initial idea was having a big bag covering the entire triangle area, but in the end I figured a half-frame bag just made more sense: I could still carry a lightweight jacket, some spares, tools and food, without compromising the two bottle cages.
Taking the first measures
Fitting the paper pattern
Benni used some water-resistant fabric and two waterproof YKK zippers on both sides.
The bag was designed in order not to use strings or Velcro straps, instead some bolts from the inside of the bag are screwed on the bottle bosses. This clever design leaves just enough space for a 500ml bottle on the seat tube, and a 700ml bottle on the down tube.
The final result is a rock-solid bag and a super clean look. Thank you, Benni!
A perfectly fitted half-frame bag
Bikepacking configuration
CONCLUSION
Building a steel frame for a mountain bike was definitively the most unexpected and fulfilling journey of the past year.
We combined creativity, technical skills, passion, a whole lot of filing—and maybe a few headaches along the way! I must say I admire Ralf’s intent to spread as much as he can the passion he has for frame building, by giving tools and knowledge to two young guys who knew nothing and from zero skills, made it to build their very own steel frames.
Sharing this experience with Ralf and Oliver is what made it really unique, and it will stay with me for a long time.
Embrace the process, learn from challenges, and let your creativity shine!
As Ralf would say: “Don’t think, just do!”
Having dinner with Ollie, Andrea, Jara and Ralf