Tim Paterek Manual - Lug vs. Tig

Figure 1. Tim Paterek's Manual

Check this bad baby out. I've just skimmed it, but I 'll be reading the WHOLE thing, swear. I mean, its even got an index and it probably weighs as much as my organic chemistry textbook (Fig. 1, 2).

Figure 2. The Insides

From what I can tell, Mr. Paterek is a fan of lugs, which got me kind of interested in lug vs. TIG welding debates. I found this article debating Lug vs Tig from Rivendell (a lug supplier), which to sum, shrugs it shoulders and reverts to, what the English call, blibber-blabber.

"But a lug is a lug, and a tig-weld ain't."

Why Lugs are Good

1. Lugs strengthen the frame at the joints
2. Lugs allow brazing, which we believe is the kindest, gentlest way to join tubes, and certainly the one which allows the easiest tube replacements.
3. Lugs are interesting to look at, and over the years there have been hundreds of styles, some proprietary, some generic, some plain, some intricate, many just plain beautiful. All lugs are interesting. When you look at a frame joint formed with lugs, there's something to look at.

Lugs used to be the preferred way to build fine bicycle frames. Then makers discovered tig-welds, and almost overnight (considering the long, 90-year reign of lugs, the 6-year period between about 1981 and 1987 constitutes overnight), tig-welding took over. It is a strong way to join tubes. It is efficient. It has proven its merit thousands of times over. A body can appreciate a good tig-weld, and should appreciate the skills that go into it. But a lug is a lug, and a tig-weld ain't.

They are beautiful, no doubt it - but I don't know - if I did choose to Lug design, I feel like some naked minimalist would be pacing behind me furrowing his brow (looking real concerned). Here is another article which supports lug soldering rather than welding:

WHY WE STILL USE LUGS

Our steel frames are lugged for two reasons. Lugs are stronger and lugs are beautiful. Did we mention that Lugs are stronger? Almost all mass-production steel frames produced today utilize cost-effective tig welding to join tubes. This prompts a question: why do we still use silver soldered lugged joining? There are two basic answers. First, properly fitted and soldered lugged joints are considerably stronger than joints created any other way. Second, they give us and other traditional builders a way of showing off. We can demonstrate, not only our soldering skill, but also how we believe a frame's details should appear.

On Strength
In the late '80s, a team of scientists in the UC Davis engineering department undertook an in-depth look at the relative strengths of various steel joining techniques at the request of "Bicycle Guide" magazine. The three top frame builders associated with the three primary joining techniques were asked to supply joining samples using tubing supplied to the builders from the same mill run. Tom Ritchie provided the fillet-brazed samples, tig-welding was done by Gary Helfrich, and the silver soldered lugged samples were done by Spectrum's Jeff Duser. The samples were fatigue tested, in some cases to failure. In most cases, the joints did not fail. More often, the tubes failed at or near the joint. The team's study involved microscopic analysis of the crystal structure of joining zones, heat effected zones and failure sites. They concluded that all three joining techniques, done properly, are clearly of sufficient strength for the purpose of bicycle frame construction. The different results obtained from the samples resulted primarily in the heat-affected areas of the tubes themselves. Not surprisingly, the tubes that were soldered turned out to be stronger than the tubes that were welded or brazed. So, what does this mean in the real world? Frames built with silver soldered lugs will last longer than those that are fillet brazed and considerably longer than those that are welded. However, for most of our customers, the real practical difference is that lugged frames hold up in crashes better, and when it becomes necessary, they are much easier to repair.

So there is a lot of merit to Lug design - ease in tube repair, stronger, and arguably more beautiful (maybe easier to put together as well? - I'm not experienced so I don't know). I hope some boot strapped practical vintage-head (conundrum?) won't be strolling along behind me when I decide to choose TIG over LUG (both three letter words that end in G, by the way). The only reason I'm choosing TIG, I would tell him, is because I've gotten advice from other experienced people, because I myself, don't really know all that I'm getting into. "This is my first bike!" I would beg as he took out his 1940's era buck knife and tried to finagle me into some kind of novel 1/2 nelson. I just hope the naked, and modern, minimalist would be there to fend off the incoming dude.