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I will be having a road race built shortly and need to decide between scandium and 7000 series aluminum. While the scandium should be minimally lighter and a bit more expensive, the main concern is responsivenenss but not terribly harsh. I would like to use for winter training as well. The size will be 51-52cm. In that size, does the material really make all that much difference? I likely will not use carbon stays since I'm not convinced they add enough if any comfort to justify the expense.
 

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Marketing hype or factual, who knows. From Easton

"Finally Easton had realized the potential of Scandium. Higher strength combined with the lower density of aluminum allowed for lighter, smaller diameter tubing. Better compliancy was realized without sacrificing fatigue life. Lighter, more lively frames. Less harshness and better feel. Easton's Sc7000 has now become the choice of cyclists worldwide."

 

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What's generally called "aluminum" in the industry is an alloy of several elements. Typically, the alloy is made up of 80-90% aluminum (Al), with other elements added in mostly single-digit percentages to increase workability, strength and fatigue resistance. Aluminum alloys are properly abbreviated Al xxx and Al xxxx, with the numbers designating materials properties.

Several aluminum alloys contain a smidgeon of scandium (Sc) - around 4% or so. To call one of these alloys "Scandium" and abbreviate it "Sc7000" isn't exactly a scam, but it certainly is clever marketing hype. The stuff is a good aluminum alloy containing a bit of scandium, that's all.
 

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Aspen said:
I will be having a road race built shortly and need to decide between scandium and 7000 series aluminum. While the scandium should be minimally lighter and a bit more expensive, the main concern is responsivenenss but not terribly harsh. I would like to use for winter training as well. The size will be 51-52cm. In that size, does the material really make all that much difference? I likely will not use carbon stays since I'm not convinced they add enough if any comfort to justify the expense.
Yeah. What wim said.

Take a gander at this. It's a bit esoteric but otherwise informative.

http://www.ameslab.gov/ric/June98News.html

"The advantages of scandium/aluminum alloys begins with metallurgy. Scandium is a potent agent when added to aluminum because its ability to refine grain size, inhibit crystallization, increase plasticity, enhance fatigue resistance, and provide greater strength to the alloy. In fact, scandium provides the highest increment of strengthening per atomic percent of any alloying element when it is added to aluminum {Acta. Metall. et. Mater., 42, 2285-90 (1994)}. "

"Ashurst Technology, Ltd., Hamilton, Bermuda, has licensed its patented AlSc Alloys and AlSc-based products, such as tubing for bicycle frames, shock absorbers and handlebars to Easton Sports for use in its Sc7000 alloy bicycle frame tubing and accessories. The Sc-Al alloys are reported to be 50% stronger than conventional aluminum alloys currently used in bicycle frames, yet are up to 12% lighter {Adv. Mater. & Proc., 152, [5] 14 (1997)}."

Sc7000 is simply an aluminum alloy with a small amount of scandium mixed in. There is apparently a great benefit to a frame's integrity using scandium mixed in as the Soviet Union had used it in manufacturing their MiGs. Don't be mislead into thinking that it's pure scandium however.
 

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Well, not quite

Antonio_B said:
There is apparently a great benefit to a frame's integrity using scandium mixed in
It would be much more accurate to say that "There is apparently a SLIGHT benefit to a frame's integrity using scandium mixed in." The scandium containing aluminum alloys are slightly stronger and therefore the tubes can be made slightly thinner and the frame, therefore, slightly lighter. There is NOTHING magic or negative in the ride of frames made from this alloy compared to any other.
 

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Kerry Irons said:
It would be much more accurate to say that "There is apparently a SLIGHT benefit to a frame's integrity using scandium mixed in." The scandium containing aluminum alloys are slightly stronger and therefore the tubes can be made slightly thinner and the frame, therefore, slightly lighter. There is NOTHING magic or negative in the ride of frames made from this alloy compared to any other.
Some people would consider empirically-derived figures of fifty percent increase in strength correlated with a twelve percent decrease in weight is quite significant and of great benefit. I would anyway.

Again, I offer: "In fact, scandium provides the highest increment of strengthening per atomic percent of any alloying element when it is added to aluminum"

Semantics, I guess. :D
 

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Kerry Irons said:
It would be much more accurate to say that "There is apparently a SLIGHT benefit to a frame's integrity using scandium mixed in." The scandium containing aluminum alloys are slightly stronger and therefore the tubes can be made slightly thinner and the frame, therefore, slightly lighter. There is NOTHING magic or negative in the ride of frames made from this alloy compared to any other.
Easton didn't expect magic at this point because (according to my sources) the magic is coming in a blockbuster news release this spring: a "scandium" tubeset with silicon carbide nanotubes mixed in. The silicon carbide nanotubes will allow the tubeset to withstand temperatures as cold as those found at the second Lagrange point (L2), temperatures as high as those in molten lava (in case you crash during the Ironman), and pressures as high as those in the Earth's core. The tubeset has no known critical stress, is 58% lighter than a beryllium tubeset and 93% as toxic when cut and dust is produced. Note that the handlebars made from this new, Uber Material will not be warrantied unless they're used with a 4 bolt stem. I've attached the ad they're placing in spring issues of the bike mags. Powerful stuff.
 

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my only experience on 2 frames

olympus zeus scandium and coppi ksc (columbus airplane aluminum)
with the same build up otherwise was that the scandium is in fact more comfortable--as in it is less harsh and transmits less to me.

granted that is not a huge comparison--but my body could feel the difference.

happy shopping
jim
 

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Aspen said:
I will be having a road race built shortly and need to decide between scandium and 7000 series aluminum. While the scandium should be minimally lighter and a bit more expensive, the main concern is responsivenenss but not terribly harsh. I would like to use for winter training as well. The size will be 51-52cm. In that size, does the material really make all that much difference? I likely will not use carbon stays since I'm not convinced they add enough if any comfort to justify the expense.
Interesting thread.
I have a 2003 Scott Team Issue, ( jean delatour ed. ) with a " scandium frame" to me this bike feels very comfortable and there are no harsness at all in the ride. After some 80hours of use the down tube cracked in two places approx 2mmm of lenght 0,3 mm. wide, due to having contacts I got it examined, and Scott did not argue about Warranty. so now I have a new set, but to me this is more or less a single season frame. I would be surprised if it will keep up for some 5 years or so. to me sub 1kg frames is not on the shopping list for coming bikes....
 

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Let's be clear

Antonio_B said:
Some people would consider empirically-derived figures of fifty percent increase in strength correlated with a twelve percent decrease in weight is quite significant and of great benefit. Semantics, I guess. :D
It's not semantics, it's a false comparison. Aluminum alloys with scandium are not 50% stronger or 12% lighter than other high performance alloys. These numbers are likely in comparison with pure aluminum. It's how marketing people get us to believe that what they are offering is somehow a miracle, when in fact it is an incremental improvement.
 

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The difference

jimcav said:
olympus zeus scandium and coppi ksc (columbus airplane aluminum)
with the same build up otherwise was that the scandium is in fact more comfortable--as in it is less harsh and transmits less to me. granted that is not a huge comparison--but my body could feel the difference.
Do you suppose there was ANY chance that frame angles, chainstay lengths, wheelbase changes, steering geometry, tube thickenesses, tube shapes, etc. were different between these two frames? Any differences between them (not to mention differences between the wheels) are much more likely attributable to these factors than to the alloy used.
 

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Kerry Irons said:
It's not semantics, it's a false comparison. Aluminum alloys with scandium are not 50% stronger or 12% lighter than other high performance alloys. These numbers are likely in comparison with pure aluminum. It's how marketing people get us to believe that what they are offering is somehow a miracle, when in fact it is an incremental improvement.
Not to nitpick Kerry, as I see you have many more posts than I do (probably meaning you're more informed on such matters as these) but had you bothered to read the paragraph I included, you would already know that the figure included therein is from a peer-reviewed publication.

I'll paste it up in case you'd like to overlook it again:

The Sc-Al alloys are reported to be 50% stronger than conventional aluminum alloys currently used in bicycle frames, yet are up to 12% lighter {Adv. Mater. & Proc., 152, [5] 14 (1997)}.

I should add that I'm not completely convinced that a scandium-alloy offers a better ride than an alloy made without it simply because I've never had the opportunity to test it myself. My arse is quite comfortable with the steel I've chosen to ride.

In any case, I simply included this information for the benefit of the poster who had posted the query.

Cheers.
 

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kerry--as i said not much of a comparison

that is why i said what i said--they were the exact same build except for the frame.
and sure it might be tubing/shaping/etc. i sold the coppi so can't check it. however the olympus is full scandium (no carbon rear) whereas the coppi ksc has a carbon rear--still the coppi was noticably harsher.
it would be better if someone out there had the exact same bike made with the 2 materials and then you'd have your answer definitively.
at least i had the frames built exactly the same--too many threads here talk about ride feel and such when the bikes are NOT built up the same.
if i stuck spinergy spox on my coppi it would probably be smoother than most bikes i have ridden--those things soak up most of the vibrations i can feel.

jim
 

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Kerry Irons said:
Do you suppose there was ANY chance that frame angles, chainstay lengths, wheelbase changes, steering geometry, tube thickenesses, tube shapes, etc. were different between these two frames? Any differences between them (not to mention differences between the wheels) are much more likely attributable to these factors than to the alloy used.
Actually the nice ride quality of Scandium tubed bikes is real and for a secondary reason. The addition of Scandium actually changes the fatigue limit and yield strength. This allows Easton to draw smaller , thinner diameter tubes resulting in a more "steel" like ride. Check the diameter of the tubes of any Easton Scandium alloyed frame and you'll notice they are smaller in diameter than Easton's EA series tubesets. Ride quality of any Metallic frame is almost solely based on tube diameter and frame style and not build material.
 
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