Now this is getting interesting. I suspect we do agree broadly, and not just about what's (not) on TV. So, as far as appropriate materials for the job go, we can probably aren't that far apart on the idea that aluminium alloy with a seasoing of scandium is probably a good idea for a tubeset - depending on what kind of frame you want to build, of course. The leaves the question of whether it makes sense for unwelded tubes, like my KCNC bars (which I like mainly because they have quite a lot of sweep); whether there is really 400kg available annually; and whether "scandium" makes sense for things like brake calipers. Last point first - I'm with you on the brake calipers, I think. In fact, as I understand it, the desirable kind of flex you can get with thinner, but stronger "scandium" tubesets is its principal advantage for building non-arse smashing frames, but brakes probably have rather different engineering requirements. The flaw in the welding argument occurred to me about 10 minutes after I edited my last post. I don't it that ends the story, however, even where bars are concerned. Small amounts of Scandium significantly increase the "yield strength" of the alloy, which means you can have tubes with thinner walls that are just as strong as thicker walled tubes of other alloys. That is a good idea for handlebars and baseball bats (thinner walls, springier bat, ball goes further; thinner walls, lighter bar, bike is lighter and still doesn't break). Sure, strong enough is strong enough, but if stronger means you can go lighter, well then, how strong is too strong? Now, on to cost and the vanishingly small quantities of the stuff that are supposedly available. These sporting goods Al alloys have less than a quarter of a percent scandium. As that paper I posted a link to points out, in high end bicycle parts, materials cost is relatively small proportion of the final cost. This is where the marketing bullsh*t comes in, and where we are definitely in agreement. There are some interesting numbers in the paper on the cost implications of adding 0.2% Sc to Aluminium - it roughly triples or quadruples the price at 2005 levels by adding about $4/kg to the price of the alloy. But the price of Sc master alloy is falling, and new supplies are becoming available which may bring that figure down to $0.8/kg. So, we are almost certainly paying more for the benefit than the materials cost justifies, which is not quite the same thing as paying for no benefit at all. Which brings us to final remaining point, the mythic 400kg. That number refers to the production of the pure metal, but the master alloy is made from the reduction of much more readily available Scandium Oxide. Even Wikipedia makes this clear: "World production of scandium is in the order of 2,000 kg per year as scandium oxide. The primary production is 400 kg while the rest is from stockpiles of Russia created during the Cold War." There is more available, I am pretty sure, in the form of recycled MIGs. When the Russian jets are all melted down, red bauxite will apparently fill the gap at a lower price. So the volume of pure metal on the market is a bit of a red herring. Also, the pure metal may be more expensive than gold, but the equivalent quantity of scandium oxide cost about $2000/kg in 2005, which is a good deal less than gold. In short, it is probably good stuff for both frames and bars, but the upcharge may well be out of proportion to the increase in the cost of the underlying materials. Rims? I don't know, but expect the same "thinner, stronger, lighter, a bit more expensive, and a bit more compliant" logic should apply. Of course the benefits are probably overhyped, as are the prices, but I think the KCNC stuff is pretty reasonable. That said, I'm not about to swap out my campy brake calipers. Ok, I expect you'll knock that one out of the park, but I hope it'll take five minutes, so I'm off to eat dinner. pistadex2009-01-27 14:06:33
