dbrk
contributor
  
Reged: 12/18/03
Posts: 201
Loc: Finger Lakes, New York
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Awhile ago I had the privilege to see a slew of frames all hacksawed up, cut across the lugs and in ways that revealed the underlying construction. A few things came to light.
First, frames without paint do NOT reveal what's going on inside the lug as far as penetration and completeness in brazing is concerned. In the vast majority of cases the frames that had poor penetration were not less safe nor were they likely to fall apart or even handle a crash poorly---though in one case a "famous" builders frame came easily apart in a crash and the view from the inside of the lug revealed work that would make even an inexpert eye look with askance. Of course, taking a hacksaw to a bicycle frame could mean that you don't ride that one again anytime soon. Everything has its price.
Second, I was repeatedly reminded that most European made frames, including those from very famous builders, are not even close in quality to even the average Japanese or American work. The brazing penetration and overall cleanliness of the job was not favorable in comparison, even though, again, this is unlikely to affect the ride or the consequences of longevity or a crash---it's almost a matter of quality that doesn't matter, in a certain way, unless you think it does. Euro frames from this eccentric point of view would never sell by quality standards in terms of build so either you like the geometry, the ride, or the romance but if you knew what was in that sausage...yikes!
Third, I gathered a new respect for Japanese builders. Of course, junk is junk and I'm not talking about that. But I saw a handful of frames from the Toyo shop in Osaka---the six person operation that currently builds for Rivendell and used to build for Ritchey before those bikes were moved to Taiwan to save money. Toyo's frames were nearly as nice as the best one-off American framebuilders just in terms of simple quality of the brazing and construction details, down to the millimeter of placing bridges and bits.
Last, the best American builders are unsurpassed when you look this closely. The VERY impressive work that I saw belonged to Curt Goodrich and Joe Starck (who no longer builds bikes). These builders so _obviously_ surpassed others that it was like day and night. I shan't mention the famous builders whose work was less than impressive in comparison but it's all in the details since, like I said at the outset, there is no reason to think that the bikes won't stay together and ride just fine.
This comment has nothing to do with geometry or design and even less to do with the "ride" which is even more intangible. But it says plenty about skills and attention and levels of detail that can't otherwise be surveyed or easily. But, to me, this was interesting to see. I'm not likely to bring a hacksaw to my new Nagasawa but there are nice pictures of it here: <http://yellowjersey.org/trnaga.html> But I would bet donuts, real, live, tasty donuts that this bike is in league with the best in terms of pure brazing build qualities---but that too we would not know with paint or without it, unless we did something _very_ painful, costly, and foolish, like hack it apart.
Sometimes on this little group I feel like I'm talking primarily to myself. Thanks for that, Kahuna. I mean, I've started every thread so far and traffic seems low, but at least I get to talk about the stuff I find interesting. Anyone out there? Got hacksaw blades? Got Italian rigs we can cut up?
dbrk
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GoJavs
new member
Reged: 01/22/05
Posts: 21
Loc: Florida
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dbrk - you are certainly NOT alone. I'm thrilled to hear you got your new Nagasawa. Unfortunately, I don't have any Japanese frames to spare that you can cut-up! I like my rb's just as they are. You have made me curious about the craftsmanship on my '95 Pinarello Stelvio? Um...
I've had limited exposure to Goodrich's work (my brother has a very nice crown-fork made by Curt), but from what I can see it does seem to be exceptional work. Starck seems to post quite a bit on bikelist.org, but I can't figure out why he no longer builds?
In any event, I appreciate your efforts in getting this forum kickstarted. I'm sure other lugged-bike lovers will find it in time!
Javier
-------------------- GoJavs
Miami, Florida
Steel? Bikes? Brilliant!
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Dave_Thompson
prophet
   
Reged: 12/19/03
Posts: 720
Loc: Spokane, Washington
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Douglas, you have a basement full of bikes with a good representation from a wide variety of builders and origins. I can come to your house with a fine-bladed hacksaw so we can inspect your bikes in detail. I'll bring good wine too.
How are you doing? What's new?
-------------------- Steel lover, but then I like Ti with carbon too.
Licensed bike geek.
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andreu
new member
Reged: 05/09/04
Posts: 21
Loc: Spain
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There is no way I am letting anyone near my Marcelo with a hacksaw, in any case it doesn't have lugs - I guess this brings me to the question or my point - can lugs hide a multitide of sins - With a TIG welded frame wysiwyg (to pinch a computer acronym)? I'd be interested in more detail on the differences between "a well lugged bike" and "a poorly lugged bike". Also, was it possible to retro strength test the join? Or is the some other factor apart from strength of the join that needs to be tested? Thanks, A
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dbrk
contributor
  
Reged: 12/18/03
Posts: 201
Loc: Finger Lakes, New York
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Quote:
andreu wrote: ...Can lugs hide a multitide of sins - With a TIG welded frame wysiwyg (to pinch a computer acronym)?
The "sin" as such is the penetration of the braze and the completeness of the work with the torch. However, like I said, whether this is done perfectly or merely adequately, the frame is very unlikely to fail. Lugged construction holds up unless it is done poorly, not just imperfectly. TIG welds also hold up well if they are done neatly and evenly or if they are done in less pleasing ways. With all due respect to great TIG welders, I think there is no aesthetic comparison between even the best TIG welds and a nice lugged steel bike. Everyone has their preferences. TIG, as far as I am concerned, is only for bikes that can't be brazed because of tubing diameters or design concerns.
Quote:
I'd be interested in more detail on the differences between "a well lugged bike" and "a poorly lugged bike". Also, was it possible to retro strength test the join? Or is the some other factor apart from strength of the join that needs to be tested? Thanks, A
When you look at the flow of the brazing material from the inside (only possible with that hacksaw...) you see how far and how evenly it moved through the lug. Also, you can see if the joint was over-heated; things scorch and burn and start to melt; none of these are good things. However, to say this again, a bike joint can put up with a lot of indignity before it fails. Further, it doesn't have to be perfectly done to be perfectly strong enough. Strong enough is not the same as perfectly done either. It's not really the strength of the joint that is at stake past a certain point of competence. Rather, it is the skill of the brazing as such which adds up to very little if things are done competently enough. When a joint is really sloppy in brazing with little penetration or a burnt joint then you may have a bike that will eventually fail but, as we all know, this is rare enough even when joints are cooked by machines and suffer other indignities as well. Looking at a lug sawed across is an exercise in "quality" that is hard to quantify: it is partly for safely, partly for competence and skill, partly for aesthetics, but all of those issues are ameliorated in light of the simple fact that bikes hold together (for the most part), that builders only have to be competent enough, and that this is a level of aesthetics invisible to the eye even if the frame has no paint.
dbrk
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dbrk
contributor
  
Reged: 12/18/03
Posts: 201
Loc: Finger Lakes, New York
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Quote:
Dave_Thompson wrote: Douglas, you have a basement full of bikes with a good representation from a wide variety of builders and origins. I can come to your house with a fine-bladed hacksaw so we can inspect your bikes in detail. I'll bring good wine too. How are you doing? What's new?
I suppose we could do this only if we drank enough before we started. I think, for the most part, I am content to know that the bikes are brazed _well-enough_ and that what I can't see even without paint is going to be left a matter of faith. I should say that the bikes that were hacksawed apart were done so to inspect deeper safety issues. There is at least one small company out there that REALLY cares about whether bikes are built safely and I am sure there are others (Specialized is famous for their testing for safety, btw).
As for me, I'm working on a number of fun projects. When it rains, it pours, this not being ideal in a financial sense but so it goes. After two years of wait, two Nagasawas have arrived: one road, the other track. I puzzle over how to build the road bike; the track bike (which is drilled for brakes and has road geometries) will get mostly an NJS-style build. Then the Saluki from Rivendell has finally shown up as well, about on time. I'll build up two, one with DA9 STI and the other with Suntour retrofriction bar end shifters, the former with modern Paul's cantilevers, the latter with DiaCompe centerpulls. Both bikes because they are 650B will get Berthoud stainless fenders. I'll post some pictures but these could take some time to build because of the details, especially fender lines, front carrier, things like that. I lean to resolved solutions rather than resourceful make it work for now solutions. And the prize of the winter season: a nearly new Bstone RB-2, in red from '94. I would rather have that singularly simple, cheap, old bit of Japanese production than, say, 99% of all the new bikes advertized in the magazines or touted as the lastestgreatest. I've only a few projects in the works including a custom Mercian made of 531 Pro tubing and then there is Cycles Tournesol. Look here cyclestournesol.com ---this is a project that will reveal a whole new commitment to being on the cutting edge of yesterday. Thanks for asking, Dave! Busy with work too! Finishing a book.
dbrk
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andreu
new member
Reged: 05/09/04
Posts: 21
Loc: Spain
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Thanks for the reply. This is really interesting. I mentioned TIG only as a reference I know this is the "lugs" department and don't want to get into a TIG versus Lugs debate.
I guess there is probably a way of doing this type of Quality Control non-destructively (at a price) I remember getting a tour of the Airbus factory in Germany and they were doing some non-destructive testing using ultrasound (I think) to look for cavities. I suspect this is a little overkill for a bicycle frame.
Thanks anyway, A
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GoJavs
new member
Reged: 01/22/05
Posts: 21
Loc: Florida
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Douglas,
Funny...with Nagasawas and Salukis hitting your front door that you describe your RB2 as the find of the winter. I too feel the same way about my '93 RB2. It's solid, steady and looks like it could last forever. Yeah, it's 25 lbs., but at the speed I go who am I kidding anyway?
Meanwhile, we look forward to seeing pics of that wonderful Mercian when it comes in. I'll have photos of my Jackson Nervex Pro up as soon as its ready!
-------------------- GoJavs
Miami, Florida
Steel? Bikes? Brilliant!
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dbrk
contributor
  
Reged: 12/18/03
Posts: 201
Loc: Finger Lakes, New York
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Quote:
andreu wrote: I guess there is probably a way of doing this type of Quality Control non-destructively (at a price) I remember getting a tour of the Airbus factory in Germany and they were doing some non-destructive testing using ultrasound (I think) to look for cavities. I suspect this is a little overkill for a bicycle frame. A
This is an interesting point. "Overkill" is likely just cost though I take your point: there is likely enough to say a frame is built well-enough using the techniques that the bike industry uses (stress tests of various sorts) and far short of the hacksaw revelation. But there are all sorts of areas in bike construction and finishing where cost is the simplest reason why things are done the way they are done. One that quickly comes to mind is paint. As nice as some paint is on bikes---say, the best of the best, like Joe Bell---the technology in the auto industry is beyond comparison (at least as Joe would tell it, not to speak for him but just to say...). In contrast, does anyone remember that video from Colnago that used to be somewhere on the Internet where the lugged steel bike was on a conveyor belt and you saw a machine heat up the lugs and at the end of the belt a real human finally put on the final touches? The certain implication was that this method was a modern technological advance when what it looked like to me was a short cut to eliminate humans with a device that did nothing to improve quality and likely diminish it (by over heating the lugs). Of course, I'd bet these bikes held together just fine. I suppose my point is that in the European mind---when they were still building lugged bikes...and Colnago still does at least partly, and I am MUCH disappointed with their tacking a plastic wishbone rear end on the Masterlight this year---the craft was meant to move along, get onto the new technology of the assembly line or something, but quite the opposite of advancing a romantic notion of handbuilt frames (which was likely always a very romantic notion).
dbrk
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Riccardo
new member
Reged: 12/17/05
Posts: 14
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A few thoughts:
A builder friend who does repairs thinks highly of the joinery of Pinarello but not of Colnago.
Any builder who doesn't learn by cutting up joints (usually test joints) doesn't know much about their brazing.
Beyond simply getting fill and not cooking the joint, there are other considerations. Regarding the fill, when silver or brass is applied intelligently, it's easy to recognize a filled joint. With practice one learns to read when the joint is getting too hot and how to avoid it. For any but the most novice brazer, missing fill is more likely caused by overcooking and boiling some of the fill out.
Other considerations are how evenly heat is applied to the joint, how quickly the braze is done and heat can be withdrawn, and how well aligned the joint is after cooling. A good brazer doesn't need to cold-set much if at all. This is good because the newer generation of tubes are much hard to cold-set. Moreover, selective application of heat to a tube can change (and improve) alignment. Its a matter of learning how one's tubes react to one's technique and adjusting the later to achieve best results.
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Insightdriver
captain
 
Reged: 03/07/04
Posts: 472
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I would like to interject that with modern controls, machines can make higher-quality joints than a human because of tight time-controls, heat-controls and positioning-controls. Only a craftsman can shape lugs in pleasing and creative ways, but machines today can do things with precision far beyond the capabilities of organic creatures.
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Riccardo
new member
Reged: 12/17/05
Posts: 14
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yur rite bout machhines cept'n ef thur uman oporaterz don't mange dem good
It all depends on the attitude of the builder(s) whether craftsman or production line
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Allan
journeyman
Reged: 05/04/04
Posts: 198
Loc: Bds,W I
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I dont think the guys over at places such as Moots would like to know that a robot welder unit would put them out of work. However i'd really like to see the comparison weld bead and penetration percentage from a machine, compared to those legendary Moots welds all done by hand.
-------------------- Its time to ride.
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Insightdriver
captain
 
Reged: 03/07/04
Posts: 472
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It's already proven in many industries. A robot, though, is only as accurate as the program that was made for it. The proper programming, using the algorithims that take into account the metals being joined, the current, type of anode material, dwell time, etc. are all taken into account. Paths can be generated mathematically and often, nowadays, cameras actually keep track of where the robot is. It's already proven their worth in all the industries that make cars and other mass-produced hard goods.
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