Tuesday, July 22, 2008

Day 3: Brazing

After yesterday, the three of us were almost scared to step in to the shop. We were asked to sleep in a bit and to come in at 9.30, and we took full advantage of the extra time. Our anxiety was not helped by the fact that today we were to learn that most intimidating of tasks: brazing. Having now made it through today, I can say that it wasn’t nearly as bad as I feared. Actually, it was the best day yet. (For instance, I'm done, and I got through with my tasks by around 6pm.)

We started by working on a lot of the things we didn’t quite finish last night. Some mitering, namely. I got my two down tube miters done by about noon, and, since the Bridgeport mill was busy, did the down tube/bottom bracket miter by hand. Going in to the course, I would have thought that mitering was something you needed a mill to do. I can now see that, with some extra time, you could do it by hand. Since I’m in absolutely no position to be buying a mill, this is reassuring. I will be able to build my second frame almost entirely with hand tools – it just might take a few months!

After lunch Doug gave us a brazing demonstration. Since he’s so skilled at it, he makes it look easy, and does everything so smoothly and with such coordination that it’s extremely hard to see just what he’s doing. Luckily he called on Dan (and not me!) to be his first test brazer. It didn’t go very smoothly for him, but it sure was instructive to see the mistakes he made. I went second, and did, I think, a pretty good job. If you keep your torch movements gentle, slow, and even, it’s pretty easy to make the silver flow without burning up the joint. See my very first joint at right: a sleeve brazed to a tube. (Ed: I forgot to take a picture!) I brazed two more sleeves after that one — the first with the assistance of Doug’s assistant Herbie (who is an incredibly good teacher) and then one again with Doug. It felt pretty natural to me, and it was really, really pleasant. Mitering was interesting and necessary, but brazing is fun! I guess we’ll see how actual brazing of lugs goes tomorrow. (But note: the "artsy loser" did better than the predictions of doom set forth yesterday, and I consider that a victory!)



Another thing, before I forget. Before I came to the class, I had assumed that a customer ordering a custom frame could have whatever sort of lugs they wanted. If they wanted Richard Sachs Newvex lugs, or Pacenti lugs all files up into a certain pattern, or Henry James lugs, they just had to say so. Well that’s not at all the case. These lugs are only made in a few angles — so if you’re lucky, and your body proportions and riding style just happen to match the angles the lugs come in, you can get them. Otherwise you can’t. For example: I was thinking about using Rene Singer lugs from Richard Sachs before the course started, but the angles didn’t work. And Richard came to class with Henry James oversize lugs, but was forced to use the Pacenti Artisan lugs, because they’re the only oversized lugs that work with his design. (This means a lot more work for him, filing them into shape.) The exception to this (and there may be others) is the Henry James lugs for standard diameter tubing, which come in a variety of angles. Fortunately that’s what I’ll be using.

A final note: I was reading the fixture wrong. My frame will actually be around a 62.5cm c-t-c. I guess that’s a lot more sensible, but I sure was excited about a monster 65cm frame.

Tomorrow: forks!

[More photos here.]

1 comment:

ralph said...

I love reading your post. very informative and makes me want to go there. look forward to every post.