are these steel or aluminum?
11-01-21, 10:51 AM
#1
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are these steel or aluminum?
They're sugino gp's. I just honestly can't tell what they're made out of.
11-01-21, 11:34 AM
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Crank arms gotta be aluminum. The rings look to be steel.
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11-01-21, 11:51 AM
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11-01-21, 12:11 PM
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Steel cranks would be roughly 1/3 to 1/2 the size of those cranks in cross-section.
11-01-21, 12:34 PM
#6
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100% right on that one.
I had a pair of stainless steel cranks laying around and I compared them. Side by side it's really obvious, but for some reason these threw me off. Thanks for all the help guys!
I had a pair of stainless steel cranks laying around and I compared them. Side by side it's really obvious, but for some reason these threw me off. Thanks for all the help guys!
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11-01-21, 02:36 PM
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That has to be easier than the water-in-a-bathtub test. 
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11-01-21, 02:53 PM
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Low end aluminum arms are sometimes chromed, so a magnet will barely attract to it. If you're not familiar with how hard a magnet sticks to real steel, you can get confused by this. Chromed aluminum arms are also really difficult to polish, unlike anodized arms which can be cleaned up easily with lye.
11-01-21, 06:14 PM
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Low end aluminum arms are sometimes chromed, so a magnet will barely attract to it. If you're not familiar with how hard a magnet sticks to real steel, you can get confused by this. Chromed aluminum arms are also really difficult to polish, unlike anodized arms which can be cleaned up easily with lye.
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