Thoughts on Lugs, Then and Now

Lugset Pre-Bike
Those who love lugged steel bicycles arrive to that preference in one of several ways. Often they grew up with lugged steel. The look or concept of it either holds sentimental value or represents quality. Perhaps their dream bike - the one they'd see in the bike shop window every day on their way home from school- had distinct lugwork. Or else lugs are incorporated into a "they don't make'm like they used to" narrative. On the other hand, a person entirely new to bicycles might simply decide they like lugs - either for aesthetic reasons or perceived functional ones.

With me it was definitely the latter. I was born in 1979. The bikes of my youth looked like this. And as far as shop windows... Well, come to think of it, I don't even remember any bike shops around when I was growing up; bikes came from department stores.

I am trying to remember how I even learned what lugs were. I certainly did not know about them when I first got into cycling as an adult. Neither did I have an ingrained preference as far as frame material. Before I bought my first grownup bike, I rode a rented aluminum hybrid in Austria - which, frankly, I thought looked kind of nice. But it rode a little harshly, and when I mentioned this to the man at the rental place he advised that I buy steel - giving me a long, expert-sounding lecture about the benefits of steel over aluminum. This was among the things that sent me in that direction.

Fast forward a bit, and I remember standing at the Belmont Wheelworks bike shop, looking at a collection of hand-cut Peter Mooney lugs through the glass counterpane. Peter Mooney was the first custom framebuilder whose bicycles I saw in person, as well as the first builder whom I would meet face to face. I knew that the filigreed objects he made were those sleeve things I'd seen on some bicycles' joints. "Those are beautiful," I said. "Yeah, Peter makes his own lugs," replied the person at the counter. And I think that's how I learned what they were called. 

So I went home and looked it up online. Until that point, the artist in me thought the sleeve things looked beautiful, but I had assumed they were entirely decorative - much like embellishments on furniture and porch railings. Now reading about them, I understood that they served as frame joints and were inherent to the frame's construction. I also found many articles and posts expressing the opinion that this lugged construction was "better" (stronger, more receptive to repair, requiring more skillful execution) than other kinds. This was even before I stumbled upon Rivendell (although it set the stage for Rivendell's appeal); this was coming from individual framebuilders and from vintage bike collectors, of whom I soon came to know a few personally. The argument seemed logical enough: Modern bikes, like everything else that's made now, were fragile and disposable. The traditional method was meant to last. And what made me particularly receptive to this argument was visiting bike shops and trying the different city bikes that were available at the time. The bikes that felt uncomfortable or seemed poorly made, happened to be welded. 

This is all simplified of course. But it's not an inaccurate summary of how my preference for lugged steel came about. It wasn't a perspective I brought with me to the blog. But it developed pretty quickly within the first year of it. 

Interestingly enough, the first stages of its unraveling had to do with aesthetics. I liked looking at bikes and spent a lot of time doing it, studying frames from different eras and different builders. I also live in an area where handbuilt lugged steel bikes are plentiful, which gave me in-person access to a lot of the custom work. One thing I began to notice, was that lugs and their various relations (fork crowns, reinforcer plates, dropout sockets, and the like) gave bicycle frames a certain aesthetic uniformity. Most framebuilders do not make their own lugs but purchase pre-fabricated sets, and there aren't many of those to choose from. And while some builders modify existing lugs to the point that the originals are not recognisable, most do not. Because of its visual distinctness, lugwork has a strong influence over a bicycle frame's aesthetic. And the more frames I looked at, the more I started to feel that the same generic details were dominating many framebuilds' work. I began to question what it was that I was actually appreciating: the creativity, the craftsmanship, or the pleasing shape of a $1 reinforcer plate? With fillet brazed and TIG welded frames I may not have cared for the look of the joints, but had to admit that the work seemed less constricted by pre-fabricated parts. 

Around the same time that my thoughts started to flow in this direction, I began to encounter an increasing number of modern, well-made bikes that were not lugged and, in some cases, not steel. Demoing the aluminum Urbana bike had a big effect on me. This excellent machine was nothing like the half-heartedly made bikes I'd grown weary of seeing in bike shops, despite using similar construction methods. The same could be said of the Paper Bike and Pilen I tried soon thereafter, not to mention custom welded bikes by ANT, Geekhouse and Seven. The association I'd formed between construction methods and quality had been erroneous. The flimsy bikes I disliked were such because they were made and assembled poorly, not because they were welded. I still preferred the look of lugs, particularly unique lugs. But my appreciation for the other methods of frame construction grew.

The growth continued as I developed closer relationships with a handful of local builders and began to better understand their methods. With this, my sense of aesthetics shifted. When looking at a bicycle frame's joint, I now see it as an embodiment of the work and creativity that making it involved, of the opportunities and limitations that were created by the chosen method of construction. This does not so much overshadow the look, as it gives meaning to the look. And meaning informs our subjective judgments of beauty.

Having now tried my own hand at building a bicycle frame, my thoughts on lugs have gone through yet another iteration. When asked what I think of them, what comes to mind is that I appreciate them making brazing easier. I don't appreciate how time consuming they are to work with and the limitations they place on frame geometry. That reasoning is entirely devoid of aesthetic sentiment, which worries me a bit. I don't want to stop "seeing." And I don't think that I will; more likely I am just a little tired now, and still overwhelmed from having gone through the process so intensely and quickly. 

I remember how, after welding two bits of steel together myself, I tried to pry them apart a couple of minutes later. The strength of the connection took me by surprise. It felt like fusion (which, of course, it was), whereas a similar joint, when brazed, felt more like it held together with very strong glue. This doesn't necessarily mean anything, I know. But I would like to learn more, and I would like to learn it firsthand. 

Indifferent is a negative word, so I would not say I am now indifferent to lugs. I like lugs, particularly unique ones. One of my crazy dreams is to design and cast a lugset of my own some day. Until then... I sort of like it all, lugs included. 

Comments

  1. It's hard not to resist a tasty, well built lugged frame. That being said, neither of my current rides have lugs - they're TIG welded and strong as nails.

    Perhaps one of these days I'll be able to convince my spouse to let me add one more frame to my collection - perhaps a beautiful lugged frame from Brent Steelman.

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  2. Ah lugs, I was in a high end road cycling shop the other day and they had a couple of columbus zona and spirit Marinoni's amongst their carbon fibre. The owner started yacking to us as I was intrigued by the new steel, but didn't like the oval weird oversized shape. and not very nicely brazed either. Lugs were deemed to heavy and unnecessary so they stopped being used in the 90's which I recall with sadness. The weird shaped tubing is supposed to stop flex. But he went on and on about carbon fibre. I want to be open minded, but horror! Yet that morning I had seen a pentalon of senior citizens zooming through Stanley Park and thought it looked fun. For years I associated top latest technology carbon fibre bikes with senior citizens because they seemed to be the only people who could afford them.
    I'm a few years older and remember lugs from a childhood perspective, recall seeing people riding their 70's road bikes all luggy and chromed....I would try riding some old bike boom 10 speeds in the 80's that belonged to friends' parents. We would fly off the handlebars and giggle. It was all bmx, but I rode my mom's old raleigh 3 speed in high school, but the early 90's onward were about mountain bikes. Road bikes vanished from bike shops and I was at a loss because I had dreamed of riding the bikes I saw when I was little. My first mountain bike was lugged, next one wasn't. I had a beat up old lugged mixte or two while at art school, such fine steel bikes disappeared from sight. If I had thought about what I was riding, I could have gotten beautiful high end lugged bikes for nothing because nobody wanted them. Now try getting a deal on a an old lugged bike
    ....then in the early 2000's I was dismayed to discover aluminium had taken over. Like anything there is high end aluminium, but most generic bikes are not and I went through a few. Overall I think aluminium was a mistake. It also corrodes something fierce which gets even better quality AL bikes.
    I discovered Rivendell and nearly died(to go to rivendell?), but of course could not afford them, and am happy to find a revival of lugged steel construction. I still can't afford anything new but have a raleigh sports much like my mom had in the 70's and a couple of beautiful lugged road frames from early 90's-that if I had been in the know might have found more suitable than that old 'katmandu' or hardrock. The funny thing about the mountain bike craze is everybody was road riding on them and wondering why it was so sluggish. What I considered 'mountain biking' could have been better accomplished on a 650b or cyclocross bike.

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    1. "For years I associated top latest technology carbon fibre bikes with senior citizens..."

      : ))))

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    2. That may have been the case at one time but the new senior citizens' material is titaniuan along with carbon and steel from any number of local artisans, and it has been that way for some time. I recall riding in the western burbs in 2003 or so and running into a Boston businessman and his son. The son had the dad's cast off expensive carbon fiber bike. The dad had the Seven seniors' bike. He also had a twin Seven in his office for those rare lunch time rides. Not that I think Sevens are only for seniors - I'd love to have one and one day will.

      Rob V. can correct me on this. My memory says carbon fiber but what struck me at the time was the son's bike was a lot more expensive than my bike, hence a seniors' bike.

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    3. "...try getting a deal on an old lugged bike."

      What's a deal? Earlier today a 51x52 650B Rene Herse rando from 1983, barely used, complete bike with a full complement of RH goodies went for $2000. Only lasted couple hours.

      At a more basic level 531 or Columbus frames with Campy ends and lugs are going for 75 to 100. Stickers are worth more than quality. A Motobecane or a Raleigh can always be sold even if it's near junk status, many excellent
      handbuilts end up in the dumpster. If the 531 sticker is missing it does not matter that the tubing can be identified by shape, the frame has little value. A Motobecane Team Champion with lots of handwork but possibly Gipiemme ends and Vitus 971 tubes and fewer stickers than what buyers expect is much harder to sell than a Motobecane Grand Touring that looks familiar. Old Motos with the Motoconfort stickers might as well be Huffys. There are lots of deals. It is currently easier to find good bikes than it is to give them away.

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    4. I don't know, those must be "johnnie come lately" seniors, the kind who just returned to adult cycling after a years long hiatus. I'm a senior, have been for a while, and I have never even considered a carbon fibre bike. Nor an aluminium one, although my wife recently bought an Opus step-through with internal gear hub and hub brakes - even a skirt guard. No, it's never been anything but lovely lugged frames for me. The only one of my 'collection' that isn't lugged is the 1965 Moulton Type I. Long live the lug!

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  3. The flimsy bikes I disliked were such because they were made and assembled poorly.

    This isn't necessarily true-they may have been poorly speced or those materials weren't a available at that price point.

    Be aware that s what you experience trying to prise tubes apart in your weakened hand condition and limited upper body strength may be construed as comfort in ride quality.

    Its important to think of these things as inter-related.

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    1. "what you experience trying to prise tubes apart ...may be construed as comfort in ride quality."

      Hm.

      Hmmm.

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  4. I think it's fairly normal for aesthetically-minded people to first connect with cycling visually, and especially with traditional, classic equipment--like well-crafted lugged frames.

    But perhaps it's also normal to evolve more toward the functional aspects of cycling the more one rides.

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    1. This was certainly the case with me--not only the bikes but the people riding the bikes--way back in the early 70's. Now it's not so much that lugs are uninteresting as much as hearing folks talk about them endlessly as something special. My current bike is simply high quality function, built and equipped with things I never would have imaged 30 years ago. And I love it!

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    2. I raced for awhile on a Colnago with extraordinary lugwork, clovers in all the lugs, Campy Super Record components with heart-shaped pivot points, a flashy paint job....the works. It was a superb bike.

      I later raced on a Ti Litespeed with Ksyriums, Campy Record Ergo etc. No artisanal details at all, but a vastly more competitive racing bike than the Colnago.

      I loved both, but the Litespeed was ultimately more satisfying because it performed better.

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  5. And lugged bikes don´t even have to be made of steel ! going with Heather topic, a senior cyclist from my neighborhood rides an 80´s Alan: carbon tubes and aluminum lugs (glued and screwed ), the thing is a beauty!.

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  6. Lug, TIg, fillet braze are all fine with me.

    As long as the bike is well thought out, aesthetics typically follow.

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  7. I definitely admire lugged frame construction, but I'm not all that picky. While most of my current bikes are lugged, or mostly lugged, there are exceptions. Over the years, most of my fleet has been TIG'd. Had a few electro-forged ones as well. I have been obsessing over getting a F-B'd frame for some time, and it's bound to happen eventually. I enjoy almost every method of frame construction, although the Kabuki Sub-Mariner frightens me quite a bit...

    These details don't bother me that much, but I will say that I have owned a couple of aluminum bikes, and ridden countless others, and they totally turn me off. And that's what really stands out for me. Personally, the material matters the most, and I can't find any love for Al. TIG'd steel looks fine, with narrow, "stack-of-dimes" welds. TIG'd aluminum looks atrocious, with floppy, "stack-of-pancakes" welds. I've never heard of fillet-brazed Al frames, but I do know that the lugged Al frames of yesteryear were notorious for early failure. Speaking of which, Al frames become riddled with little dents at an alarming rate. (Ok, there are exceptions and some of these things lasted: http://classiccycleus.com/home/1936-monark-silverking/ )

    I get the benefits of Al: it's stiff, lightweight, cheap, and ubiquitous. I'm not trying to talk anyone out of it. It just gives me the heebie-jeebies. I'm not into Ti or Carbon, either, although those materials don't crinkle my nose the way Al does. It's been a cliche for decades, but steel really is real. I don't intend to ride anything else.

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  8. It's way easier to learn how to braze properly than it is to weld. Lugs were designed to make production easier and cheaper since TIG wasn't a thing way back when. Now that there are so many TIG weldors in the world it's not such a saving.

    Personally I find most neo-classical styled bicycles that seem popular on this and many other bicycle sites to be overwrought and almost tacky when the lugs get way too ornate... BFD someone can use a coping saw and a file!!! OMG

    I don't buy the rivendell kool-aid that modern frames are made to be disposable because they don't use lugs. They don't need to use lugs anymore because TIG welding is more economical and more than strong enough for a bicycle. Despite the protestations of "luggites" the science of metallurgy just keeps on advancing and lugs are obsolete.

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    1. "It's way easier to learn how to braze properly than it is to weld."

      This is unambiguously true, I think.

      The rest of what you write is one side of an old argument that plays out like a broken record anytime it's started. In a sense both sides of that argument and right and wrong, at the same time. Only thing left to do is to make what you like, ride what you like. Lots of options available now no matter what you are into.

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    2. The real craftsmanship with lugs comes after the brazing.

      There are some builders - Peter Weigle, Tom and Jeff at Spectrum, Johnny Coast are my examples - who are exceptionally adept at filing the lugs so the end disappears into the tubing. Peter especially is also a master at modifying his lugs such that the form engages in a perfect dialogue with the function of the part.

      Tig, fillet, lugs all have their good points. Lugs well done can be just as exceptional as the perfect Tig or fillet.

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    3. Let's be fair here. I have seen plenty of TIG-welded steel frames from the 80s that are still in service and doing fine. I have seen plenty of Electro-forged steel frames, dating from the fifties, that are still kickin', too. And a friend of mine has a late-60s(we're guessing...never bothered to look up the serial#) fillet-brazed Schwinn Supersport that is peppered with surface rust but still totally intact. So, yes, GP is absolutely, 100% *wrong* when he claims that frames without lugs are somehow "disposable".

      Yes, it is easier to replace a spent tube within the context of a lugged frame, but I've yet to meet someone IRL who has been thru this process. Folks type about it online all the time, and it is theoretically true, but it is rarely practiced, and rarely necessary.

      Are lugs obsolete? Absolutely not. To be sure, you can make a frame without them now, but that has been the case for over a century. Lugs do, indeed, add to the cost and weight of a frameset (all other things being equal). But, there's still a place for them on the market, as evidenced by the large volume of lugged frames being sold today. I think that, at least among road bikes, the steel frame will survive primarily in the form of lugged construction.

      They still press music on vinyl, too... and ppl still buy LPs. Eclipsed, perhaps, but not exactly obsolete.

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    4. I still like lugs but I think they are just fetishized a bit too much these days. The rivendell marketing material sounds a bit too preachy and while I can respect the experience GP has his approach doesn't work for me. As a welder I can appreciate the beauty of a nice fat stack-o-dimes tig bead too, dunno why some "luggites" have to slam that kind of craftsmanship and skill in order to promote lugs. Lugs are pretty all on their own but since they come pre cut and polished it's easy to pass off mass-production as hand-crafted too. Older lugs needed way more work to get them pretty so I guess if someone wants to recreate that and call it more authentic it's fine but I dunno, seems kind of pointless to me.

      As someone who has brazed on production lines it's not really all that much fun, I can see why a one-man shop type place would be fun to work at but I'm fine letting robots to all the welding for bicycles.

      I volunteer 20-40 hours a week at a co-op so I'm pretty jaded when it comes to "bicycle culture" as a whole and even the disposable nature of everything in our society. I work as a welder (when I'm not volunteering) and I used to braze for a living too, so I know enough about bicycle building that there isn't really any mystique to it, or most other type of metal fabrication.

      I guess the mystique of something wears off if you already know how it goes together and comes apart... and having to trash hundreds of nice (and mostly not-nice) bicycles I've really become detached from them... so yeah. Sorry for being trollish with that anon post up there.

      Check out my flickr for some of my rescued bicycles... I only have one modern aluminum bike now (I still love it too!)

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    5. My sister has inherited my mother's 80s ladies touring bike, (a raleigh lady richmond) and last year someone crushed the top/upper downtube while the bike was locked to a pole. As the bike hd sentimental value as well as a reasonably nice 531 frame, she had a frame builder replace the tube; so I know at least one instance of tube replacement. I don't know that it would be that much more effort to replace a tigged tube, depending on the frame alloy.

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  9. I like lugs because...well...I like lugs. More seriously, every bicycle I've owned since I was 17, with perhaps one exception, whether gaspipe or Reynolds, has been lugged. I don't think it's that I go looking for lugs, but they just happen to be there. Since I graduated high school in 1976, it may just be that the bikes that appeal to me have a lot in common with the 10-speeds of my college years, and those were, of course, lugged. Dunno. But I have seen some truly lovely bikes without lugs as well.

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  10. 'That reasoning is entirely devoid of aesthetic sentiment, which worries me a bit. I don't want to stop "seeing." And I don't think that I will; more likely I am just a little tired now, and still overwhelmed from having gone through the process so intensely and quickly.'

    this makes little sense to me.....you won't stop seeing, nor do you have to, it's who you are. you now see better, as it should be.

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  11. I think the "lugged look" became very popular again because it works as a signal of authenticity and craftsmanship in a world where mass production is perceived to have overwhelmed everything. (Ironically, in that lugs were a technology used to facilitate mass production themselves.)

    With the resurgence of handmade, craft, well designed mass-produced, etc. bikes, I think view that only lugged steel is "authentic" has also begun to fade.

    To me it sounds like your personal change of perspective is more driven by deeper experience with bikes' design, performance, and manufacturing. Most people don't get this level of exposure. And yet many of us seem to be moving in the same direction. Are you driving the culture or is it driving you?

    More specifically, are lugs a sign, signifier, token, or a glyph? hmmm

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    1. We are driving each other around in circles? Cycling rather; no one is doing any driving.

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    2. touché - are you drafting the culture or is it sucking on your wheel?

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  12. It's nice to hear of your evolution. We all evolve and dialogue is more meaningful when that premise is understood. You're not unique in your thinking about lugs and their importance or their benefits or aesthetics.

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  13. I think lugs are lugly - lugly bicycle!

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  14. You left out the main historical reason for lugged building. The traditional bicycle tubes could not tolerate the heat of welding. The amount of finish work does not really reflect how well the bike rode. It was often commented on how poorly finished the true race bikes, (as opposed to commercial bikes), were finished.

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    1. So, these days I wonder if lugs are more or less frivolous, sentimental?

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    2. They are just one out of several approaches you can take to joining a frame's tubes. As with the other methods, there are pros and cons to them. Many reasons to use lugs that are friv/sent-free.

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    3. no, i get...just say'n

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  15. I like lugs, but sometimes they do make a bike look like it was built by William Morris elves; it makes my eyes tired. I do appreciate a square-cut 1940s gas-pipe bike lug, simply for the emphasis on utility

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    1. "William Morris elves..."

      Hey, they need jobs too.

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    2. Or possibly in the age of the Sun King. I periodically google modernist lugs, or something similar, but I have yet to find a boatload of alternative designs. Nothing like a modern fluoro cyclist all pimped out in the latest Jetsons gear, riding a bike with Fleur de Lys lugs. Fusion!

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  16. My favorite style is brazed. Liquidy, smooth, and unadorned. Lugged is next.
    Stack of dimes tigged - just can't develop a taste for it. I know it delivers the most strength for fewer dollars that you can get. A vendor who has to deliver warranties along with their frames to get bike-shop business would do well to consider them. And I'd look for one for a gravel-grinder or a mountain stump jumper. But I'll never have one IN my house, it would be a garaged bike. And I'd never put polished components on it either, as it wouldn't deserve them.

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  17. Connecting lugs to elves, hobbits, gnomes, otaku monks is neither accurate nor good sales promotion. Lugs were the dominant way to join frame tubes for a bunch of generations and they still work quite well. There is a reason for those $1 plates. They do make the frame stronger. TIG welded frames get seat collars and gussets under the downtube and maybe rings around the headtube - lugs just means you decided to do the full monty in advance.

    Norman Taylor walked to the shed in the morning and built a frame. After lunch he did the racks and the stem. Bernard Carre built two frames a day for decades, if they were only to wear Gitane stickers he might build three. It was work. Factory builders went much faster.

    The old formula "one craftsman, one week, one Cinelli" was for real but the week started with whittling down a massive sandcast lugset, bracket shell and crown to half their size and perfect Cinelli form. After the frame was built it got polished to the nth degree to prepare for chrome. Even what wasn't to be chromed had to be very good because the Milanesi paint went on thin. And still the one week formula entailed magnificent patronage from Cino - all his subcontractors had their own frames and their own clients. Building a frame is only monkish and time-consuming if you want it to be.

    There have always been builders who saw their work as artistry. Good. It's one way. Probably there are more artist/framebuilders in lugged steel in the US right now than anywhere else ever. There are builders like Chris Kvale or Columbine Cycles who have never built anything short of a showbike and still treat it as a job, sell the bikes at fair and very competitive prices, and send the customer out to ride without a lot of fuss.

    Lugs are vocabulary. You can say a lot of things in lug. It has to be the most fully articulate way to build. And after a century of refinement the good ones ride well indeed.

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    1. "TIG welded frames get seat collars and gussets under the downtube and maybe rings around the headtube - lugs just means you decided to do the full monty in advance."

      Welding doesn't require these things, there was as simultaneous evolution in the design of bikes. So at that time stuff like adjustable height seat posts for going downhill were coming into vogue, That thing that looked like the spring in a safety pin. People might adjust a seat more times in one short ride than a classic bike would be adjusted in it's lifespan. These dictated different parts. There is also an art to correctly strengthening tube joints. But when art gets into it, whether lugs or spider web gussets on choppers, they usually strengthen the wrong part, which leads to tube crushing in crashes. Form follow function, if you let it.

      "Norman Taylor walked to the shed in the morning and built a frame. After lunch he did the racks and the stem."

      In part because when we moved from the only way, to the gnomy way, all kinds of silly claims had to be sustained. So you have people assembling tubes on surface plates. No harm in it really, and in the post industrial world those beautiful plates are getting sold to people for wood stove fire breaks, but the time and silliness it takes to pretend to align tubes to the thou, does tend to slow stuff down.

      "Lugs are vocabulary. You can say a lot of things in lug. It has to be the most fully articulate way to build. And after a century of refinement the good ones ride well indeed."

      Unfortunately the voice is pretty odd with all the 18the century doo dahs built into the shapes. Welding has at least as much voice, but people are not familiar with the vocabulary to the same extent. One needs a cartoon like symbolism to snag the punters. People can't read the welds, or the structures they make possible as easily as looking at spades and clubs.

      Tom

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  18. This is an old entry, so it might be strange for me to comment on it now. But I'd like to say that your blog first got me into preferring lugged steel bikes, so this is an interesting direction you've taken. It was through reading this blog that I saw how ugly the giant weld marks on my hybrid are. Which is amusing.

    You also got me into mixtes, though I can't ride them very well yet. I am alas, still a fairly clueless n00b.

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    1. "It was through reading this blog that I saw how ugly the giant weld marks on my hybrid are. Which is amusing. "

      If they look like droppings of mud where there is a splat above the surface and a rounding under before they meet the tube. Amazingly that kind of stuff works, but it is a bad/cold weld and quite common on Chinese frames, motor lifts, etc... But dimes, that is an amazing thing. Liquid metal pooled and each set with heat controlled by hand with an electric arc, and a through a brighter than the sun halo. Magic really.

      There is a lot of talk about hand work that is generally pretty ignorant, and can mean some predictable process like running a milling machine "by hand", or even using hand tools, which are in fact normally quite predictable. That is why there are so many of then, each does one little thing without much skill required. But real hand making, like freehand drawing, or clay, or TIG, is relatively rare. But the guy who uses highly predictable patterns, to stencil out some lugs is the artist.

      Construction wise TIG is to lugs what riding a bicycle is to riding a bus.

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  19. Nobody seems to have mentioned one simple fact. When you're joining pieces of steel together, the less heat you use, the better. Welding, which is done at a high temperature, causes all sorts of undesirable changes to occur in the steel, such as a predisposition to rusting. Those of us who were car enthusiasts some years ago will remember that every old Mark Two Jaguar you saw had a line of rust down the front mudguards (fenders), corresponding to a weld on the other side. Welding temperatures also anneal, or soften, the steel. In some processes, like making clock springs, the steel is re-hardened afterwards, but not in ordinary car, motor cycle or bicycle manufacture. The very best bicycles were silver-soldered. I think this was true of Schwinn Paramounts. Brazing is hotter, and is fine in the hands of a craftsman, whose touch, instinct and experience will prevent him (or her - many bicycles were put together by women in factories like Dawes and Raleigh) from overdoing the heat. It's a fine line to tread, though. One of my bicycles is an MTB dating from about 1999, with welded joints which have been nicely ground down and finished, but a lot of welded bikes are anything but aesthetically pleasing. Lugs spread the load over a larger area, but a weld presents a narrow line where failure can occur in the future.

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  20. "Nobody seems to have mentioned one simple fact. When you're joining pieces of steel together, the less heat you use, the better."

    Not true.


    - Many tubes made today are actually air hardening, which means they get stronger with heat. I can take the other side of that argument, but won't bother here. Manufacturers make the tubes to either be stronger after welding, or the strength that is missed is not needed, see butted tubing.

    - It isn't just how hot, it is how long and how much. Even if we were worrying about heat, which we shouldn't, not all heat is the same. OA (as used with lugs) torches are so hot they will melt a steel welding wire held 7 inches off the flame. The heat affected zone from lugs and brazing is hot enough, and lasts longer, and that does weaken tubing. But we needn't worry, see butting.

    - How is the heat affected zone shielded. Even if we were worrying about heat, which we shouldn't, the heat affected zone in TIG is either conpletely shielded, or shielded on the outside. It has to be or the steel would simply burn away. But the upside is that the shielding is far more advanced than on other processes. But it doesn't matter either way, see butted tubes.

    Most of the nonsense about heat is no longer talked about by people in the know. Since the first world war when the Germans pioneered the use of metal 4130 tubing in their aircraft, these tubes have been welded. That is what they are designed for. It is one of the Big Lies one comes across that this is some big problem, as if there were Italian craftsmen lugging together all the miles of tubing in nuke plants.

    The misunderstanding arises from a partial understanding of the damage heat does to steel or steel products. But humans have understood the tricks around that since they first forge hardened carbon steel. In the modern world the trades of toolmaker and steel worker, etc... are separated, as are the processes and materials used. If one floats around the various trades one runs into people who have picked up that in the other trade there is this big problem (like ruining the temper of a tool), they assume these problem affect their structural steel in the same way, when they don't. Understandably the materials have been engineered for specific processes and the cheapest workers possible, who don't see the full picture, but you get blowback from that also.

    " Welding, which is done at a high temperature, causes all sorts of undesirable changes to occur in the steel, such as a predisposition to rusting. Those of us who were car enthusiasts some years ago will remember that every old Mark Two Jaguar you saw had a line of rust down the front mudguards (fenders), corresponding to a weld on the other side."

    Probably wasn't TIG, and the back side wasn't shielded, and the steel wasn't anything you would find in a bike. They had a time horizon in mind that didn't include the cars being used today. 2-5 years.

    "Welding temperatures also anneal, or soften, the steel. In some processes"

    Not so much, but the process of drawing temper as you mention below starts at temperatures well below the melting point of silver solder, and further still below brass. This is the misunderstanding referred to. I temper tools at around 400 degrees F, and springs, I forget, I think around 500. By definition a braze is a solder type process that takes place over 800 degrees, so it makes no difference whether you braze, solder, or weld these materials, temper wise. It's gone in the HAZ. Silver solder used on bikes is misnamed, it is the lowest heat but over 800 braze we commonly find. There is actual silver solder that works at very low temps, but it is nothing like strong enough for our uses.

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  21. "like making clock springs, the steel is re-hardened afterwards, but not in ordinary car, motor cycle or bicycle manufacture."

    True because their performance does not depend on it. See butted tubes. 953 is a sort of exception, and of course aluminum, but not for most steel. And after the initial 953 nonsense, they just sell it like any other butted tube, hardening is no longer done by most builders.

    "The very best bicycles were silver-soldered. I think this was true of Schwinn Paramounts. Brazing is hotter, and is fine in the hands of a craftsman, whose touch, instinct and experience will prevent him (or her - many bicycles were put together by women in factories like Dawes and Raleigh) from overdoing the heat. It's a fine line to tread, though."

    Silver is a braze it operates over 800F, it is cooler than brass. Talk about treading lines is for amateurs. Pros repeat to mind numbing cycles the same process and never mess it up. Difficulty is normally irrelevant, and in an industrial process highly undesirable, because you have to pay people. In frame building courses the brazing side is easy enough that students also within the same week get to build a fork. With TIG they are still struggling not to burn through, far more skilled.

    "One of my bicycles is an MTB dating from about 1999, with welded joints which have been nicely ground down and finished,"

    One is not really supposed to grind down welds. The weld is essentially a casting, like many modern lugs. If you grind through the lines of deposition, you open up stress risers. Better to bondo it on up. Or if you are supremely skilled there are guys who can lay a perfect fillet without dimes, I am in awe of Don Ferris. When I write that about grinding it has a bit of a sound of the other myths out there, but that is what we are told.

    "but a lot of welded bikes are anything but aesthetically pleasing. "

    Beauty is in the eye of the beholder, I just think it is sad that a more resolute attempt hasn't been made to actually explain TIG, and it's beauty.


    "Lugs spread the load over a larger area, but a weld presents a narrow line where failure can occur in the future."

    I don't know if there is a category of Lugs Engineer. I do know there is a very broad and well researched area known as welding engineering. Most of us are dependant on the performance of welds at some point in each day. The actually size of the fillet required in a weld is about a radius 2x as great as tube thickness. So standard weld radius would be less than 1.6mm. Yet one rarely sees a radius anywhere near that small. The real mystery is how they get the fillet as large as they do on tubing as thin as it is, without blowing through or cold welding. And why. That is the question one should ask.

    Of course fillets on Al bikes can be enormous.

    Tom



    Sorry didn't realize the size limit, will do better next time.

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