Hi,
i usually hang out in the recumbent section but i recently had questions about exactly how "green" the bicycle industry and bicycle production in general is. Aren't there nasty waste substances involved when welding a frame? are they worse for different materials? And where does the steel/aluminum/carbon/magnesium come from anyways? do they make frames from scratch, or use preassembled pieces, or what? How hard is it for a small builder to make one from "scratch" (or as "scratch" as possible)? Are there any notably "green" bicycle makers? (I know Chris King components are really good, but i don't think they make frames. Shimano claims to be concerned with the environment, but they don't make complete bikes either.) thanks

The whole bicycle industry is "green" in my opinion. I'm pretty sure that ALL the toxic waste from the bicycle industry in one whole year is a fraction of the toxic waste produced by even the "greenest" auto maker in a DAY! Plus, once the bike is made, it produces very little toxic waste for the rest of it's life. Like maybe the old tires, tubes and the like. But how many bicycle tires could be made from just ONE car tire? And a car uses 4 of those tires!
Sooooo....

What's your point?

Be assured that I do not intend to put down the bicycle industry in any way at all. I just would like to make sure that the bicycle I build will not produce noxious waste that the earth could never break down. Are there any such cases with welding metals together? I realize that bicycles are probably about 3000 times more green than autos (which makes me proud to be a biker), but I do see the possibility for irresponsibility because of that fact. I don't think that the "we're already greener than cars, so we have a little leeway" viewpoint is too green. While I know that we will probably never be able to achieve an earth that is as clean as we would like it, I want to do as little damage as possible. I'm not trying to rag on you framebuilders. I just wanted some information about the welding process and about its waste products if any. I know next to nothing about welding and metals in general except for the fact that they compose my lovely little bike .

From a frame perspective i don't think welding is a big deal. There is very little actual welding in a frame. Meaning that while obviously it is one of the key steps, it is a fairly trivial amount of work. When I am welding I am using about 20-30 amps of a total 150, that tops out around 30 amps input. So I am using about 5 amps input, about the same as a loaded electric drill.

The shield gas used is inert. The welding wire is just more metal.

Now behind all this stuff you have the electronics industry, the electrical power industry (my welding juice is all nuclear), and the steel industry etc... But what we all do with that stuff is pretty benign.

The paint used is probably a bigger at source of production problem than anything else.

Aluminum is a lot more consumptive than 4130. So maybe we are talking about running several electric drills for a while...

Yep eg China loadsof bikes no pollution but as economy grows and cars become the norm pollution will be as bad as Tokyo

China's pollution does not come from autos like here in the states. China is currently driven by coal which causes 85% of the pollution issues that have global effects. The current issue is over the emerging middle class in China and the most dramatic increase in car ownership in the world. If they make the jump to a hydrogen based society (which they are in an almost perfect position to) then they will probably be the new middle east in hydrogen production.

What's the trick there? Don't then need titanic amounts of conventional energy to "make" Hydrogen?

Not really but 90% of Hydrogen is currently made using fossil fuels, but that will change as new technologies are created. My point about China was more that they are in a position to leap frog to a hydrogen society and become the global leaders in the technology. They don't need to wait for a capitalist system to make it financially feasable, they can make a governmental mandate and push it.