Framebuilders - Does anyone make a glued lugged frame?

Glued might be the wrong word. I would think an aerospace bonding agent similar to what they use on plane wings would work well and not alter the composition of the metal like welding can do.

thats why lugged frames are lugged. So they can be brazed (less heat). But to answer your question; Not to my knowledge. The closest thing I can think off are the ones made of plastic.

oh and those bamboo ones.

the raleigh technium frames from the late 80/early 90s were "bonded". my mountain bike has an aluminum top tube and downtube, with the rest of the frame being cromoly, including the head tube. mine was made in the early/mid 90's- i haven't cared enough to track down more info on it. its still together, so i can't complain.

Miyata made an aluminum lugged, ti tubed bike. Bonded is the word they used. They failed occasionally as did the Raleigh Techniums. They stopped making them.

Regular lugs don't have enough surface area, so you'd have to make a lug which would require welding/brazing anyway. Bruce Gordon has recently done a bonded ti lugged bike with what looked to be regular lugs...but that actually involved fabricating much more complex lugs- they have to have an inner and outer sections to bond to. A bonded frame like that would be far more expensive than a regular frame.
Really, the heat is a non-issue w/a lugged steel frame. Bonding is for parts that can't be welded.

Weren't the Grafteks bonded and lugged? I rode a bonded aluminum Trek 1000 for almost 20 wears, and I regret getting rid of it everytime I post about it. grrrrrrrr. It was not lugged, but it was an incredible bike to ride. Very stiff and responsive.

The Italian company ALAN made a lugged/bonded aluminum frame (http://james.architectureburger.com/cycle/alan.html) in the 70s. "Screwed 'n' glued" we called it, because the tubes were actually threaded into the lugs and held with epoxy.

my mountain bike has an aluminum top tube and downtube, with the rest of the frame being cromoly

When those break, you have to go get the special welding rods that has aluminum on one side and steel on the other.....really tough to find.

Key here is as mentioned above; the lugs are different for a bonded frame compared to a brazed frame - bonded lugs have a lot more surface area since the bonded joint strength is lower than brazing.

Glued might be the wrong word. I would think an aerospace bonding agent similar to what they use on plane wings would work well and not alter the composition of the metal like welding can do.

Vitus frames were built with aluminum or carbon fiber tubes bonded to cast aluminum lugs:
http://equusbicycle.com/bike/vitus/brochure/index.html
The aluminum frames were/are very light with a reputation for flexibility, while the carbon-tubed "Carbone" frames were even lighter. The earlier carbon frames suffered from galvanic corrosion and joint failure.

Alan still makes bikes with carbon tubes glued to aluminium lugs. They probably aren't the only ones.

http://www.alanbike.net/2009/index.php/cyclo-cross-2009/top-cross

Mike Burrows and his recumbent tricycle (Windcheetah) Speedy etc... still uses bond or some new product from Loctite to bond the cast pieces to the main tubing. Not sure of the temps required to heat it out for repairing problems.

Place I work for makes space reflectors using different forms of bond to build liteweight alum/graphite tubing structures.
DH

Bruce Gordon makes Titanium lugged frames - titanium 'lugs' with titanium tubes bonded in - but any competent builder could do that as it's no different to bonding carbon to carbon or Ti to carbon.

Anyway, welding does not alter the composition of the frame at all. A properly welded frame is for all intents and purposes an homogeneous structure.

Bingo on the welding. There can be oxidization from welding. just as there can be traggic denting in the shipping department if people are incompetent. There can be heat effects, but they run the gamut, generally no important change, sometimes an adverse change, and also welding can induce positive changes due to heat effects.

"thats why lugged frames are lugged. So they can be brazed (less heat)."

That's what they say, though lugged frames were probably brazed initially, because they didn't know how to weld them, or need to worry about it since the steels were simple. Welding of bikes goes back 100 years. Welding light tube airframes was once a pretty "air age" kinda thing. The Faulker factory used it to good effect and promoted it in the post WWI period in the US. Not sure when it jumped to bikes, or from what point of origin.

Lugged frames are currently brazed to sell frames that people like to buy, as made by people who like to make them. This process is advanced by the deployment of of some pretty sketchy arguments. End result is very good quality.

My friend has a bonded Miyata with Ti tubes and Au lugs. The epoxy did fail on the stays, I repaired it with JB Weld after consulting my friend at the shop. It was that or spend $80 on the epoxy from the factory. He thought this would be the direction he would of personally would of taken also.

Those Al glued and screwed frames from Vitus and Alan used to rule in cyclo-cross events but they are considered old fashioned now.
Quite a few carbon frame makers including Time, Look, Colnago use carbon lugs and tubes. This allows more choice in sizeing and geometry without the expense of a separate mould.
You also get bikes with titanium lugs and carbon tubes. The ti lugs are actually welded into the correct angles and often have really pretty designs cut in which also distribute stress. Basically its showing off.

Many modern carbon frames are actually of glued modular construction, Trek, Cervelo, Felt... etc etc.

http://www.youtube.com/watch?v=2nVbmcnsXXs

I have exxon graftek lugs if your interested. E-mail me at dpowers@harris.com

I have exxon graftek lugs if your interested, email me at dpowers@harris.com

I have a late 80's aluminium Peugeot Comet that incorporates glued tubes. I still ride it 100- 150 miles a week with no problem.

Thats a sharp bicycle.

I had a couple questions along the lines of this subject. First I was curious if anyone sells carbon lugs? Also, do the carbon rear ends that you glue into a steel sleeve/lug made by Columbus, etc., does this make a lasting frame? And finally, do these carbon rear ends save much weight over a steel rear triangle made out of a medium-light weight steel. I rode Look frames for a long time and they are the best riding frames I have ridden. If there was one bike frame I wish I had built it would be the 595. Luv it.

On the subject of bonding, has anyone powder coated a bonded frame? I have an old Technium that I was thinking of refinishing. I really don't want to powder coat it and have it fall apart. Nobody seems to know for sure what temp the frame can be subject to without the glue failing.

the raleigh technium frames from the late 80/early 90s were "bonded". my mountain bike has an aluminum top tube and downtube, with the rest of the frame being cromoly, including the head tube. mine was made in the early/mid 90's- i haven't cared enough to track down more info on it. its still together, so i can't complain.

I own both a Raleigh technium mountain bike and a road from this timeframe. Both are luged and bonded and they have been going strong since I bought them, I dont ride them often anymore since I have purchesed newer bikes. I dont like down tube shifters.

George

Our custom Zona tandem has handmade carbon fiber lugs (with window cutouts).