mikeread

Custom Bicycle Frame ? Aesthetics of Design

Doing a bit of googling and stumbled across this article. I thought you might find it interesting/amusing :-)

Andrew R Stewart 

As I read this blog I noted the various mistakes in the tubing and lug references but then the shot of the welded lugs came up and my heart skipped a beat. Not sure I'd want to be seen riding this frame

This blog does show the new generation coming to frame building that has little exposure to the traditional ways, design and execution. For better or worse... Andy

Nessism

NO!

unterhausen

The owner is gonna die and it will improve the species.


rejecting tradition is the way of designers everywhere. That's how new things happen. But it also means they are constantly learning the lessons that others have learned many times before them.

dsaul

I am more concerned about the grinding than the welding. The welded joints weren't pretty, but they appear to be good enough to make a rideable frame. His attempts to smooth out the welds by grinding have undoubtedly removed material from the tubes and compromised their strength.

TiHabanero

Good night Irene! Function over form?

CliffordK

Those are long weld joints with a lot of material that is welded.

So poorly fitted, and covering it up with welding, grinding, and tapering the welds so almost all the added weld material is gone.

I believe the lugs are designed to have internal support from the brazing/soldering material. So, in this case, almost all the lug support is at the tips of the deeply ground welds.

I don't know, I might ride it, watching it carefully, but I'd certainly be concerned about the joints, and would inspect it regularly.

GrainBrain

I had more of the sharp, short intake of breath. A gasp?

You're telling me he went to all this trouble but didn't research how to join everything? Then he goes on to state that he'll be brazing on some other bits?

Besides grinding away the welds I'd be worried about the metal fatigue from the heat.

CliffordK

It appears to be new sourced tubing.

Columbus Max Niobium Steel I'm not seeing anything that specifically notes whether or not it is considered a weldable alloy.

Ahh, found it in the catalog. The MIG wire probably isn't the Columbus suggested wire, but the typical MIG/TIG wires tend to be very hard, and probably would be fine in itself.

That appears to be MIG welding, but not a bad looking bead for many of the welds, and should be little different in effect at the welds from pure TIG welding the frame.

Except, of course, the style of welding and grinding.

One other note. Trapped moisture, and especially trapped salts could do nasty things to that frame.

Cantona

Dread to think what it will look like once it's painted.

unterhausen

he did have a picture of Max, but then he said it was standard dimensions. Which would mean SL, I think. Same tubing material though. I suspect there will be bondo involved in the finish. I thought the welds looked reasonably good except at the ends of the beads. Couldn't really tell what was going on there. But when he ground them down it seemed like they were okay. If it starts cracking, it's going to be at one of those points.

duanedr 

That is what I noticed. On the DT at the HT especially there is quite a bit of material removed from the downtube. I can only imagine how thin it is in that highly stressed location.

unterhausen

seems like it is student work. The prof is in mechanical engineering.

CliffordK

The project is called Aesthetics of Design. I presume part of the goal was to build sleek lugless tapered joints.

But, of course, that could have been done with either Filet brazing or Nova sells an internal lug set.

https://www.cycle-frames.com/bicycle...ZE-FRAME-.html

Or, one could do traditional brazing the joints, then filet out slightly beyond the end of the lug and smooth it down to a nice taper.

FrameBuilders Supply also sells blanks that might be easier to shape as desired.

https://framebuildersupply.com/collections/lugs

I suppose an advantage of brazing lugs is it is easier to visualize material layers when finishing.

rando_couche

I wouldn't trust it any further than I could throw it. It's amazing that he didn't burn right through the tubes.

David Tollefson

Not even on the trainer...