Tuesday, January 1, 2008
Vacation Frame Building Camp
Talking to frame builders is a dangerous business. If you do it enough, you begin to think you know the craft. You start to develop your own ideas about frame geometry, the lines of a seat lug and how your name for a bike would be way better than what is out there.
Disabusing us of these ideas isn’t the business of the frame builder. Rather, we are left to our own devices and either we learn just how skilled the torch bearers are, or we decide to take up the craft ourselves. A few years ago, I was invited to take a middle road.
For those who follow the ranks of juniors, Toby Stanton is known for producing more national championship winning riders than any two coaches combined. Jonathan Page, Robby Dapice, Jesse Anthony, Larssyn Staley, Saul Raisin and Will Frischkorn all called him coach. He also builds and paints frames under the label Hot Tubes and in the late 1990s he began teaching frame building classes to the curious.
The class takes the uninitiated from un-mitered tube to painted frame. Choices along the way include lugs or TIG welding, not to mention the opportunity to design your own logo. Some in the industry have expressed some skepticism about Stanton’s ability to impart all that a frame builder needs to learn in a single 9-5 week. He is clear with everyone the workshop is not a trade school for future professionals, though that's not to say builders haven't apprenticed under him. Upon my arrival he stated repeatedly, “This is about your comfort level; you can do as much or as little as you want.” You could say it is frame builder fantasy camp—a guided tour, if you will.
For me, it was the perfect opportunity to test my theory that a ‘cross bike with a lower BB would corner more easily. What we settled on was a cyclocross frame with a 59-centimeter seat tube (measured center to center), a 58cm top tube, 42cm chainstays, 43 mm of fork rake, parallel 73-degree seat and head tube angles and the kicker: 7.5cm of bottom bracket drop—a full centimeter lower than most ‘cross frames. With a set of road clinchers this bike would have the bottom bracket height of a traditional Italian stage racing bike, about 26.5cm. Toby walked me through the steps for producing the drawing, which detailed the angle of each junction and each tube’s length down to the millimeter. We then mitered each tube and began fitting them together in the frame jig.
While the experience wasn’t meant to make you think like a framebuilder, Stanton’s coaching gifts came into play as we moved through each step. He would ask questions about each step to see if I understood why we were doing things in a certain way. Each question served to illustrate the methodical thinking a good frame builder must use to produce a strong and straight frame.
Most tubes received two cuts per end: one for the angle and one to conform to the round profile of the tube. I deburred each end on a belt sander, filed each edge square and Dremeled the inside of each lug smooth. Only then did we begin brazing.
The first thing I learned about the torch was that even though silver has a low melting point, we were working with temperatures in excess of 1000 degrees Fahrenheit. I had the skittish demeanor of a schoolboy trying to light a roman candle from 50 paces. Stanton passed his hand 10 inches in front of the flame without wincing. In doing so he demonstrated the most crucial facet of the framebuilder’s craft: heat is dispensed only where it needs to be. With a flame as small as he uses (he, like many builders, uses the smallest tip available: #0) what he waves around has all the focus of a camera lens opened up to F2—virtually no depth of field. What he gave me to wave over the joint had nothing in common with a flamethrower.
On the four joints of the main triangle he broke me in gradually, demonstrating first and then handing over the torch and silver rod. In a few spots where I seemed to have trouble coordinating torch and rod he let me hold one while he deftly wielded the other. Trying to heat the seat tube/bottom bracket joint while holding the silver rod in the right spot and see the joint without having some part of your anatomy brush up against hot steel is a little like driving a stick for the first time.
I burned up some flux, left some globs of silver and, in short, did what seemed really questionable work. Stanton’s voice was even and patient: “Okay, now you’re burning up the flux, so back off on the heat.” Once the brazing was complete, the filing began.
We had done nothing to alter the basic line of the lugs themselves, but I wanted to make sure that I thinned the points as well as removed all the casting seams. For an experienced builder the process is simple, but for the uninitiated, a minute can go by while you try to choose the right file to work on a curve. It seemed as if Stanton could remove in three file strokes what it took me ten or more to accomplish. Builders will talk about how silver is soft; don’t believe them. Silver is still metal and this precious element doesn’t file away like the wood in a Cub Scout’s Pinewood Derby car. Day two ended as day three would begin: with me filing.
By the time we brazed the fork my skill had improved dramatically, but I still waivered between so little heat that I bent the silver rod rather than feeding it in and heating the joint to the point that the silver was practically sucked into the joint like a chocolate bar into the maw of a five-year-old.
We checked both the frame and fork for alignment and I attempted to hide my amazement: They were as straight as a Nevada highway. Stanton handled the sandblasting and painting duties, though I understand he now guides students through these steps as well.
In 40 hours (maybe a bit more) we went from uncut tubes and a simple theory to a finished frame. After baking the paint overnight, I assembled it into a bike and raced it a day later at ‘cross nationals.
Given the long nature of this post, my riding experience will come in a subsequent post, an unexpected Part III, if you will.