Lugged vs. Welded Steel

[serenaslu]

I am considering a steel frame as a possibility for a badly needed new bike. The last steel that I owned was an old Ross back in the early 80's. What are the advantages/drawbacks of lugged vs butt welded construction on modern frames. As an example two frames I have been considering are the Torelli Countach and Mondonico Futura Leggero. Both made by the same company from the same tubing, same geometry but one pin-lugged and one TIG welded. Only about 3 oz and $150 difference. Thanks

 

[boudreaux]

Originally posted by serenaslu
I am considering a steel frame as a possibility for a badly needed new bike. The last steel that I owned was an old Ross back in the early 80's. What are the advantages/drawbacks of lugged vs butt welded construction on modern frames. As an example two frames I have been considering are the Torelli Countach and Mondonico Futura Leggero. Both made by the same company from the same tubing, same geometry but one pin-lugged and one TIG welded. Only about 3 oz and $150 difference. Thanks

Functionally no different if equal quality of construction. Some people just like lugs better,but everything else being equal there is usually a bit of a weight penalty. Both are quality frames by a top builder.I just like lugs better...YMMV.

 

[531Aussie]

This web page is a very enjoyable read, especially if you're leaning toward steel (http://www.henryjames.com/faq.html); it tells you all the things you want to hear.

Infact, after reading this you'll probably never want anything else but a lugged steel frame, but you've gotta remember, Henry James is VERY pro-steel.

 

[Doctor Morbius]

Originally posted by serenaslu
I am considering a steel frame as a possibility for a badly needed new bike. The last steel that I owned was an old Ross back in the early 80's. What are the advantages/drawbacks of lugged vs butt welded construction on modern frames. As an example two frames I have been considering are the Torelli Countach and Mondonico Futura Leggero. Both made by the same company from the same tubing, same geometry but one pin-lugged and one TIG welded. Only about 3 oz and $150 difference. Thanks

I have just the article for you. Enjoy!

http://www.mmsonline.com/articles/109505.html

From article:
In the manufacture of lug frames, the tubes were cut manually to a required length with a milling machine. One end of the cut tube was inserted into a lug, which was a pre-formed metal piece made into the desired angle for a particular bike frame. Lugs came in different sizes and shapes to fit a variety of tubes. A brass charge contained in the collar of the lug melted during a brazing process. As the melted brass cooled and solidified, a brazed joint is formed between the tube and lug. Upon inspection, if rework was needed, it had to be done by hand. Finally, the bicycle frame went through a pickling procedure to clean off the black residue left by the flux from the brazing process.

"Obviously, this was a very time-consuming, labor-intense and potentially dangerous process," said Mr. Wilkinson. When Raleigh began making changes in the bicycle design to respond to the consumer demand for mountain bikes, the Waterloo facility had to look at different methods of welding the frame together. Welding was an impressive alternative because it maintained quality consistency, which ensured Raleigh's high manufacturing standards.

With welding, metal is fused to metal, eliminating the high costs of brass charges and pre-fitted lugs. "Welding was a less expensive manufacturing process that produced stronger joints and looked more attractive. So welded frames quickly replaced lug frames," said Mr. Wilkinson.

 

[boudreaux]

Originally posted by Doctor Morbius
I have just the article for you. Enjoy!

http://www.mmsonline.com/articles/109505.html

From article:
In the manufacture of lug frames, the tubes were cut manually to a required length with a milling machine. One end of the cut tube was inserted into a lug, which was a pre-formed metal piece made into the desired angle for a particular bike frame. Lugs came in different sizes and shapes to fit a variety of tubes. A brass charge contained in the collar of the lug melted during a brazing process. As the melted brass cooled and solidified, a brazed joint is formed between the tube and lug. Upon inspection, if rework was needed, it had to be done by hand.

With welding, metal is fused to metal, eliminating the high costs of brass charges and pre-fitted lugs. "Welding was a less expensive manufacturing process that produced stronger joints and looked more attractive. So welded frames quickly replaced lug frames," said Mr. Wilkinson.

There is alot of hooey in that article. Welding is a higher temperature process than brazing,especially brazing with silver and can have a much more degrading effect on the material. Newer air hardening alloys negate that effect,but were not around when that article was written.Welds don't necessarily look better and some are downright crappy. Welding is just simply cheaper for mass production, and can be done by robots. That does not mean that quality frames cannot be built by skilled craftsmen tho. The 'brazing' process described is the one used on junk and low end frames and not the method used in quality work.

 

[ewitz]

I would liken this argument to oxen to plow the fields or horses.

Enter the era of modern frame materials you Luddiites.

 

[fushman]

Originally posted by ewitz
I would liken this argument to oxen to plow the fields or horses.

Enter the era of modern frame materials you Luddiites.

no, like said above the only real difference is expense so your analogy is stupid

 

[dhk]

Originally posted by boudreaux
There is alot of hooey in that article. Welding is a higher temperature process than brazing,especially brazing with silver and can have a much more degrading effect on the material. Newer air hardening alloys negate that effect,but were not around when that article was written.Welds don't necessarily look better and some are downright crappy. Welding is just simply cheaper for mass production, and can be done by robots. That does not mean that quality frames cannot be built by skilled craftsmen tho. The 'brazing' process described is the one used on junk and low end frames and not the method used in quality work.

Do you think torch brazing a lugged frame with silver would be a way to go for the homebuilder who doesn't have the equipment and skill to do TIG welding? I've been thinking this would be the way I could build a steel frame at home. Not a cost-effective deal, but a good winter-long project...I used to enjoy brazing with a torch.

 

[boudreaux]

Originally posted by dhk
Do you think torch brazing a lugged frame with silver would be a way to go for the homebuilder who doesn't have the equipment and skill to do TIG welding? I've been thinking this would be the way I could build a steel frame at home. Not a cost-effective deal, but a good winter-long project...I used to enjoy brazing with a torch.

Silver takes more skill than brass.Tolerances have to be closer,and silver will not fill misfits like brass.

 

[dennis dee]

Originally posted by boudreaux
Silver takes more skill than brass.Tolerances have to be closer,and silver will not fill misfits like brass.

Silver (960 degrees cent.) has a lower melting point than brass (1083 degrees) and therefore has less chances to thermally weaken the tubes than when working with brass.

 

[fushman]

Originally posted by dennis dee
Silver (960 degrees cent.) has a lower melting point than brass (1083 degrees) and therefore has less chances to thermally weaken the tubes than when working with brass.

ya but apparently the cons outweigh the pros for an amateur builder

 

[armchair_spacem]

Originally posted by serenaslu
I am considering a steel frame as a possibility for a badly needed new bike. The last steel that I owned was an old Ross back in the early 80's. What are the advantages/drawbacks of lugged vs butt welded construction on modern frames. As an example two frames I have been considering are the Torelli Countach and Mondonico Futura Leggero. Both made by the same company from the same tubing, same geometry but one pin-lugged and one TIG welded. Only about 3 oz and $150 difference. Thanks

Lugs start to become difficult if not impossible to find (and correspondingly expensive) if you want other-than-round tubing profiles and/or uncommon angles. This may not be the case in bigger markets but it certainly is here in the Antipodes. Some builders even fabricate their own, but that brings the expected cost.

 

[jkwas]

They are both good. To me, lugged steel requires more skill and time, with extra attention to details. That means in all likelyhood a more experienced craftsman built it.

 

[dhk]

Originally posted by jkwas
They are both good. To me, lugged steel requires more skill and time, with extra attention to details. That means in all likelyhood a more experienced craftsman built it.

To me, fine TIG welds without lugs take more skill, because there is nowhere to hide poor joint fits or inconsistent weld bead. But, no doubt both types require plenty of time and skill to do well.

There are certainly many examples of poorly built lugged frames around. My 30 year old Raleigh Grand Sport, built by the Carleton Frameworks, is one of them.

It could be that the more experienced craftsmen continue to build lugged steel frames simply because those were the high-end frames 20-30 or more years ago when they built their reputations, and they have no need to change.

 

[comprex]

www.richardsachs.com

dhk, take a look at the discussion of fork crowns.