snipped from text: "...But what is the head angle? Obviously he had to make every fork the same and there had to be some charts or formulas to go along with this system of narrow parameters for frames. " and: " It turns out the "55" is the "cutting length" of the top tube."
B2, the head angle is a resultant measurement. he would've built to a prescribed front center, most likely arrived at based on size, setback, tt length, and rake chosen. as such, the angle <is> what it <is>. and: the eeeenies measured the top tube from the point of the seatlug to the crutch behind the headtube lip.
e-RICHIE chester, ct
On Fri, 23 May 2003 09:25:45 -0700 Brian Baylis <rocklube@adnc.com> writes: One thing did get my attention. There was a Confente on display, frame #7 I believe. On display was the "build card" Mario used to write the dimentions of the frames. Having heard various things about how Mario went about building frames, which has always seemed awkward to me BTW; this build card sort of caught my attention. The first thinh I noticed was that this 62.5cm frame was speced with a 55 cm top tube. I looked at the frame and could tell the top tube was longer than 55 cm. I measured. It measured 57.5cm or thereabouts. That is more "normal" for a bike that size. Hummmmm. So why did the card say 55cm when it was actually 57.5cm? I also noticed a seat angle was noted at 73 1/2 degrees or so but there was no head angle given. At the bottom head lug there was an "S2" written in. No bottom head lug angle was given but I knew that Mario used to begin a frame by brazing the head tube to the down tube. VERY odd place to start a frame. I believe there were only 3 templates he had for these bottom head angles. That means that head angles on all frames are whatever results from the bottom head lug angle he uses. Odd. So how do you establish what angle to miter the top tube/head tube junction? It turns out the "55" is the "cutting length" of the top tube. But what is the head angle? Obviously he had to make every fork the same and there had to be some charts or formulas to go along with this system of narrow parameters for frames. Needless to say none of this works for full custom frames of a wide variety. I've heard that the related "book" does exist and I am going to check into it to see if learning more about it makes the system more understandable. Right now it seems like an odd and very limited way of building frames. Since I am a Confente owner now myself, I'm a bit more curious how he went about the process. I noticed that frame #7 and frame #24 have simular "traits" in the paintwork. Interesting.