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Trial by fire: Remembering the Bicycle Academy

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Pete Muir
7 Dec 2022

In 2017, Cyclist spent two weeks at the Bicycle Academy to see if even the most inexperienced craftsman can really become a framebuilder

With the sad news that the Bicycle Academy in Somerset has permanently closed, we turn the clock back to 2017, when Cyclist spent two weeks at the  Academy to see if even the most inexperienced craftsman can really become a framebuilder 

Words Pete Muir Photography Adam Gasson

The brass rod wavers in my hand as I try to direct it into the millimetre gap between the nozzle of the brazing torch and the steel tubes that will, one day, become my new bike.

I mentally run through the checklist from my brazing tutorials, aware that if I spend too much time thinking about the process I’m likely to overheat the metal and damage it.

Tilt the flame, angle it into the join between the two tubes, a little bit more on the thicker tube to even out the temperature. Wait… not too soon with the brass rod or it won’t melt. Hold it steady, gently tease it into the join, wait… wait for it to give… there.

Now move! Bring the torch round a touch, don’t let it raise up, watch how the brass pools, spreading at the edges – not too much – now add some more brass quickly, move again, dab again, hold the flame steady.

‘Good,’ says Tom, who has been monitoring my progress. I step back, heart pumping, eyes aching, and inspect my handiwork. So far I’ve managed to complete about two inches of brazing work on the junction between the head tube and top tube and already I’m exhausted.

Tom releases the frame from the vice and rotates it through a few degrees, and asks me if I’m ready to continue. I will have to repeat this process several more times just to join these two tubes together, and we haven’t even got to the fiddly stuff around the bottom bracket yet.

I’m starting to rethink my preconceptions about what it takes to become a framebuilder.

Back to school

Like many people who work in an office, I have often dreamed about jacking it all in and moving to the countryside, where I will while away my days creating objects of beauty in my artisan workshop, a radio on in the background and a lazy dog asleep in the corner.

For me, the main obstacle to realising this dream is my utter ineptitude at all things practical. I can’t hang a picture without accidentally punching a hole through to the neighbours’ living room. The last time I built any kind of vehicle it was out of Lego, so I don’t fancy my chances of becoming a celebrated bicycle framebuilder any time soon.

Andrew Denham, a former engineer in the oil industry and founder of the Bicycle Academy in Somerset, assures me he can teach me everything I need to take those first steps towards my dream, should I decide to pursue it.

He believes that bike framebuilding has become unnecessarily shrouded in mystique and his aim is to demystify the process, distilling it into a format that can be explained, taught and understood.

‘Making a frame is in part the physical process of measuring, marking, cutting, shaping and joining the tubes together, and those things are not particularly challenging.

‘If you go into any industrial estate you’ll find people doing things like that every day, but they’re not celebrated in coffee table books,’ he says, although that’s not to undermine the skill it takes to create a great frame.

‘Making a frame that has any kind of value is about underpinning the design and having an appreciation of how you can refine its ride qualities and fit, and how you can work the material to get the most from it.

‘The reason I set up the Bicycle Academy was that nobody was really making any effort to communicate those bits of information.’

The Bicycle Academy isn’t the only place where people can go to learn how to make a bike, but Denham believes too many other courses have tutors who may be highly experienced framebuilders but are less adept at explaining what it is they actually do.

‘With many framebuilders the process has become so ingrained it’s effectively a case of muscle memory. They can produce wonderful results but they are unable to articulate how they do it to other people, which is why they tend to perpetuate this idea that you only become good at it when you have done it for many years.’

This emphasis on teaching the principles of framebuilding – rather than simply going through the motions of constructing a frame – is why the Bicycle Academy course is two weeks long, with much of the time spent in the classroom rather than just at the workbench.

Most of day two is spent with Denham, learning about brazing theory. He proves to be a passionate and articulate teacher, bringing scientific clarity to a subject often considered to be a dark art restricted to master builders.

There are only two pupils in the classroom – myself and Jean-Philippe, who has come over from Belgium to do the course – and we learn about the different welding and brazing methods, types of fillers, flame speeds and temperatures, flux, fillet shapes and depths, capillary action, stress risers and how heat affects steel.

On other days we are given lessons in bike design, geometry and structure by Tom Sturdy, who is not only a framebuilder himself but also has a background in aerospace engineering, holds a masters in biomechanics and is a former professional triathlete.

By the end of the classes my head is spinning with concepts like Young’s modulus, mechanical trail, yield strengths and hip rotation. We have discussed the variables that affect bike handling and argued about the relative merits of frame stiffness (I finally understand why aluminium bikes tend to feel harsher than steel, despite steel being three times stiffer than aluminium).

All I have to do now is put this knowledge into practice, preferably without slicing off any of my limbs or burning down the workshop.

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If at first you don’t succeed…

My plan is to build a road bike frame that I am grandiosely describing as ‘modern classic’. That is, the geometry is fairly traditional but it will be made from oversized Columbus Life tubing to keep it light and stiff by steel bike standards.

In my mind it will look like something that could have been created by Pegoretti, and passers-by will swoon over its refinement and elegance.

Jean-Philippe, by contrast, intends to produce a rugged mountain bike with a belt drive, which requires some complex planning, including the removal of a chunk of chainstay to accommodate the disc brake rotors, and a splitter in the seatstay to allow the fitting of the belt.

Fortunately for Jean-Philippe, his job requires him to TIG-weld industrial workbenches, so he’s already comfortable with the brazing torch.

I, meanwhile, have never done anything like this before, which is why a large proportion of our time on the course is spent practising brazing over and over again, under the watchful eye of Sturdy and fellow framebuilder Jake Rusby.

My first attempts are risible. We’ve been told to make a ‘stack of coins’ on a flat metal surface by creating small circular pools of brass that overlap each other to form a long fillet, but by the end my brass stack looks more like a worm that has been fought over by two birds.

Equally tricky is mitring tube ends with a curved file so that they form a perfect fit with other tubes. Each swipe of the file removes a tiny amount of metal, changing the shape of the mitre by minuscule degrees.

It’s a time-consuming and infuriating process: take a few strokes with the file, remove the tube from the vice, line it up with its partner, check for gaps, return it to the vice, take a couple more strokes, remove from the vice… now the gaps are on the other side.

Repeat again and again until you either have a pleasingly airtight seal or you have filed away so much material that the tube is now too short and needs to be thrown away.

It will be several days before we’re let loose on the tubes that will make our bikes, and I’m thankful for the time to practise the techniques and discuss all the elements of the final frame that need to be considered.

What type of bottom bracket should I be using? Do I want bosses for mudguards? What kind of seat clamp do I want? Should I go for a braze-on derailleur hanger?

I find the whole process fascinating. By working on my own bike, I have a better insight into which aspects are fixed by necessity and which can be manipulated to my own preferences.

I have a new appreciation for the skill and effort required, and my eyes have been opened to many of the myths and fallacies that surround framebuilding.

As Denham puts it, ‘Making a bicycle is absolutely a process. It’s not an art. It’s not about what music you listen to or whether you’ve got the right beard. Our motivation here isn’t to diminish the value that’s associated with framebuilding, I just want to demystify it, to stop it becoming this impenetrable, revered thing.’ 

Bicycle shaped object

It’s the end of the first week before I finally begin work on the bike proper. My chosen Columbus tubeset sits shiny and pristine on the workbench, and I am nervous about making the first cuts into the steel.

The tubes are butted – thicker at the ends than the middle – so it’s important to consider how much to remove from each end before wielding the hacksaw.

I measure the tube wall thicknesses using the brilliantly named ‘butt-checker’, then mark the tube for cutting. Then I measure it again. Then I get Jake to measure it. Then I do it once more for luck. Finally I pluck up the courage to slice into the precious metal.

Over the next few days, I meticulously mitre and measure all the tubes, and it begins to form the shape of a bicycle frame in the jig. I braze the dropouts into the rear stays, teasing the filler around the spaces with the flame.

I check groupset manuals to ensure there will be no issues with clearances. I drill breather holes in the tubes in preparation for brazing. And each day ends with more fillet brazing practice.

By now I’m getting the hang of it. I’m still far from expert, but elements of it have become natural enough that I can focus on the important stuff: the height and angle of the flame; watching the filler to see it flow into the root before dabbing the rod; feeling it shift ever so slightly in my fingers as a tiny amount melts into the pool; gauging the depth and width of the fillet, and moving at just the right speed to keep the pool liquid without burning the filler.

All the practice pays off. I manage to successfully braze all the tubes together, and by the final day of the course I am in possession of a handsome bicycle frame that I can say, with a certain amount of pride, I have made myself.

The question now is whether I could take the skills I have learned onwards to become a genuine artisan framebuilder in my country workshop?

I believe the answer is yes. It would take a lot more learning, a lot of extra practice and many more frames before I would put my name to one, but the essentials are there to get started should I want to. But would I want to?

I’ve discovered that framebuilding is certainly not the leisurely pursuit I’d envisioned in my office-bound daydreams. It requires patience and focus, with many laborious, repetitive tasks.

It can be stressful and frustrating, and that’s before you start dealing with awkward customers. I decide I will need to give my future plans more consideration, perhaps while riding my new bike into work each day.

Before I can ride my bike, however, I need to get it painted, and I’d like to smooth back the fillets to give it that polished, professional finish. Tom demonstrates how to scrape back the hardened brass with a flat blade and emery paper, and I give it a go. It seems to take a very long time to do even a small patch.

‘Yes,’ says Denham as he sips his tea. ‘To do the whole frame will take about 40 hours.’

Ah. That workshop in the country seems further away than ever.

Paint maketh the frame

Ian Patterson of Cole Coatings in London talks through the frame-painting process

‘When your frame came to us, it had a touch of corrosion because it had sat for a while, so we sand-blasted it to make everything smooth. The next step is to “key” it – adding a texture using abrasives so that we can get a mechanical bond.

‘We then give it an epoxy primer and allow it to cure for three days before keying it again so the primer bonds with the paint.

‘After painting we add a transparent base coat where the graphics will go. We custom cut the stencils for graphics, stick them on and heat them to remove any bubbles.

‘For this frame we dusted two or three coats of white for the graphics. We remove any stencils, mask up areas such as dropouts, then seal the building so there’s no dust around. We suit up, and then we clear-coat.

‘We wait a week for it to cure so that the clear coat is firm enough to polish. Only once the surface is perfectly smooth will it be allowed to leave the shop.’ 

For a closer look at the fruits of Pete’s labours, check out his What We Ride feature on his self-built PM road bike


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