Grind freely?
#1
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Grind freely?
Like many of you, I have some NR era Campy cranks with cracks in the webs. I have one (at least) on a bike and a couple others put aside. I've been hesitant to take a file to them, worried that I'd screw them up and only make matters worse.
The other day, while searching for something else, I came across an orphaned SR Apex right crank arm. I was surprised to see how much material from that section SR removed. I realize they didn't do it in a haphazard fashion, but I think if you replaced the missing material, you'd probably be left with about the same profile in that area as a garden variety Campy NR/SR crank, including the sharp edge which would leave it susceptible to stress risers.
So, grind freely, my friends. (I think.)

The other day, while searching for something else, I came across an orphaned SR Apex right crank arm. I was surprised to see how much material from that section SR removed. I realize they didn't do it in a haphazard fashion, but I think if you replaced the missing material, you'd probably be left with about the same profile in that area as a garden variety Campy NR/SR crank, including the sharp edge which would leave it susceptible to stress risers.
So, grind freely, my friends. (I think.)
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#2
When you look at that crank you can certainly appreciate the beauty of the NR forging and finishing. There's a lot of material on the NR. But I'm reluctant to grind too freely myself. Of course, you have to go deep enough to get rid of the crack. But if the crack is deep you can end up removing quite a bit of material and it looks kind of funny. Plus you remove the anodizing in that area. Once you put it on the bike though, it nearly disappears. I've only had to do it once, thankfully.
#3
I would not hesitate to grind enough to eliminate the sharp-edged stress-risers and smooth and contour the backside of a Campy crank...but that SR Apex does NOT look like the model to follow to me. I can't follow what SR was trying for in milling out that much material right there (maybe for chainring clearance with their BCD), plus there are still sharp edges, just not in the same place as on a Campy NR.
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