I would like to hear people's thoughts/tips/criteria for evaluating craftsmanship of vintage frames. Another recent thread started to discuss what constitutes sloppy craftsmanship. Rather than hijack that thread, I thought it would be useful to create a new thread to discuss tell-tale signs of a well-made or poorly-made frame. We all know when we see chipping paint and/or chrome, or beautifully detailed lugs, but it is not so obvious (to me at least) whether the welding and brazing was done well. If an apprentice and master builder were both given the same tubeset and building specs, what would distinguish the two frames in the end?

Indicators of poor workmanship

Little balls or smears of brazing material on the tubing or lugs.

Insufficient braze material such that the fillet is starved.

Excessive braze material such that the fillet is a bulge rather than a fillet.

Uneven filleting (size of fillet is not uniform).

File marks or sanding marks on the lugs or tubes.

Welds that are unevenly ground down.

I look for excess or deficiency of material in the welds and/or brazing. I also look for proper tubes that haven't been crushed or dented. I also look for symmetry in the frame. Asymmetry of more than a small amount is often a telltale sign a car has backed over the bike and someone has tried to straighten it out poorly.

I also look for straight forks and clean drops that don't have serious dents or deformities.

I'm not really looking for perfect, but what I'm doing is eyeballing for damage or cheap workmanship.

Really nice brazing--my Ebisu's seat cluster:


Not-so-nice brazing--my '72 Raleigh International's seat cluster:


Neal

Neal, when I finally make it to Boston I will happily pay admission to come gawk at your bicycles.

Heck, I'd come take that ugly & unappreciated International off his hands. While in town, maybe I could trade it to Scott for something more interesting.

Thanks for the feedback. Neal, those photos sure make it more clear!

Something I've noticed on my LOOK frame is a "thinning" of the point of the lug at the top of the downtube by the headtube.

Here is a photo:


And for comparison, the seat cluster:


What might cause differences in the thickness of the lug points? I should add that the downtube on this frame was replaced many years ago. Is possible this lug was thinned during the replacement of the downtube (though there is no thinning at the BB lug)?

P.S. Neal, what is that beautiful braided brake cable housing on your Ebisu?

File marks under chrome-Yuck!

Gaps under lugs where brass didn't flow.

Excess brass/silver around lugs.

more pics of bad stuff vs good stuff would make the differences clearer I think.

No admission fee necessary! Just try not to mutter, "Is this guy crazy, or what?" or (which is more common) "Wait until I tell my wife/spouse/partner; and she thought I have too many bikes."

Don't presume it's ugly and unappreciated just because of that photo. Well, actually, the '71 International is pretty ugly with lots of corrosion and a few dents to add to the worksmanship, but it's one of the best riders of the fleet. I was on it today to head to a distant grocery store. In fact, I like the Raleigh International so much that I currently have three of them (including the '74 frameset, which I got from Scott in exchange for some choice Fuji-esque parts).

neal

The thickness of those points is a function of how much filing was done. I've had some frames in which you could cut your finger on those lug points. I don't think that's quite the idea.

That housing is the "metallic braid" cable from V-O:

https://www.velo-orange.com/vocahoki.html

Neal

Clean shorelines, no undercuts, smooth lug surfaces.

I don't think it really matters. Some of the brazing I've seen on highly desirable frames has been rather poor, in fact that is quite common.

Just messing with you. I'd give one a try before flipping it that fast, unless something silly was offered to me. Maybe if I ever make it out to Boston, I'll hit up his Fuji collection and your English one.

There are many cans o' worms to be opened here. But those photos of lug thinning are useful. When cast lugs were introduced, much less of that was done - cast lugs can be thinned. But it's a little harder than with pressed lugs, and cast lugs were widely embraced in part because they needed less work to be presentable and therefore saved money. The aesthetics of this kind of thing are hard to pin down, and to some extent subjective. There was a school of lug filing following Albert Eisentraut that went for super-thin lugs, which some folks find overdone and maybe a bit showy. Check out Mark DiNucci's work in this tread:
https://www.bikeforums.net/classic-vintage/339945-images-mark-dinucci.html
Many folks feel that the idea is a degree of thinning that makes a smooth transition between the lugs and the tubes, creating a sculpted, flowing look that over- or un- thinned lugs can't capture. Check out the sculpted quality of this De Rosa, which I used to own (in particular that exquisite lower headlug):
https://www.flickr.com/photos/2358521...7618581982271/
A lot of handwork went into that De Rosa and the DiNucci I posted above. Nothing against the Look frame, but there's much less handwork there (very astute to pick up on the fact that some apparently at least took the trouble to shape the lower headlug).
I personally like the very thinned lug look as well, except when it's excessive. I also like cast lugs when they're very tidy with clean "shorelines" and contribute to the overall aesthetic:
https://www.flickr.com/photos/yangeva...7606035181695/
Very different look Samson is going for (monster framebuilder, by the way - Harada, I believe).
Once you can distinguish which frames truly represent top level handwork, the key is to decide what style/elements you admire and why. There is a lot more to it, obviously.

We don't need no stinkin' lugs!



Neal

Be aware that paint can hide a multitude of sins. Sometimes it can be a real shock when you strip a famous-maker frame for repainting.

And here we come to the crux of the issue, atmo.
Look at some of the famous marques, and here I'm talking about frames
revered in racing circles. Sometimes the lug work was horrible, filing? maybe a few strokes for
fit, not finish. These were tools of the racer, not some holy grail work of art. I've seen a few
Italian frames sans paint and they ain't pretty. Thats not to say all of them are that way, but a
lot are. Take some of the big French marques, the poor workmanship is legend, then so are the
number of races won on those same frames.
I would say the trend towards more artful lugwork, filing etc. started in England and was
carried over to the U.S. with the big surge in custom builders in the 70s.

So is that all there is to a quality frame is the quality of the brazing at the lugs?

I suppose there is no way, at least by looking, to judge the quality of the ride. Have to just get on it and ride? What to do if there is just a frame and
fork?

I'm really glad you asked this...I'm learning a lot...

On my International, and to a lesser extent the International in that thread, the lugs look dripped on. There is a lack of uniformity. If you look at Kurt's, it's even worse. In contrast...my Raleigh Professional faux Team looks extremely sharp.

Ride quality is very subjective in any case. But as mentioned above, there's more than brazing (which can be hard to asses with the paint on, as also mentioned). There's also the way the lugs are filed and finished, and the way the tubes are mitered. Checking the interior of the bottom bracket shell to see how the tubes are mitered can be a big clue as to the attention the frame got from its builder. Then you can look for little clues as to the extra effort a builder may have gone to. Take Grandis frames, for instance. Many from the steel era have an extended tang on the bottom bracket that is a separate piece brazed on to create the extension - it's a bit of a "signature" flourish that tells you the builder took pride in his work and was willing to take the time and make the effort to make it distinctive. That's just one tiny example.
It's also very true that plenty of frames with big reputations don't evidence really careful attention. Doesn't mean they were merely "tools" - aesthetics is usually involved to some extent. It's just that the builder may have been cranking out a bunch of frames and didn't think anyone would be poking around inside the BB shell to assess the mitering and identify shortcuts he may have taken. In Italy, for example, a lot of US frames from some of the newer, filing-obsessed builders emerging in the 70's were dismissed as over-finished or "filed to death." It's a different sensibility as to what defines or determines "craftsmanship."
And it's also very true that craftsmanship in the sense it's being discussed here is not the same thing as ride quality or durability - lots of sloppily built frames ride great for decade after decade. But often someone who has refined his or her skills as a builder has refined their whole act - aesthetics and good frame design into the bargain. In this respect, sometimes the "handed-down" principles help and sometimes they hinder.

Clean mitering and joinery in the bottom bracket. (like Piccio Special just mentioned... actually, I think he summarizes the topic quite well)

When we get into ride quality, that's when we get into whether the forks are straight and whether the frame has damage or bends in it. We also get into frame angles/slackness etc. That's often about geometry and measurement.

+1. And fit (correct frame for rider) and fitting (correct stem, seat post position, seat position, &c).

Body filler, the painter's assistant for good perceived value of the final product.

I agree any number of "fine" bicycle makers can be variable.

A finished bike will show the attention to the lugs prior to brazing and attention after. Overheating can sometimes be seen with the paint off depending on how the bike was prepped for painting. Obviously one cannot see this with the paint coat on. In general, if they bothered with the lugs they probably cared in the construction throughout.

The French are probably the poster child for showing poor workmanship but an effective frame. The Italians can go the other way, pretty where you can see it, maybe not elsewhere.

There are plenty of sound straight frames that show poorly on the outside, they will always be the last to get asked to dance but will make a pleasant partner when you get to know them.