On Tue, 13 Dec 2005, Dan DiMaria wrote:
> OK, I'm probably revisiting an issue that's been visited a thousand times,
> but I did search Google (got a few teases but nothing substantial) and the
> Classic Rendezvous Archives (found nothing). What's the consensus on the
> small stress cracks where the crank arm meets the spider? Is the crank
> trash? Does filing it after the fact do anything or is it too little too
> late? For that matter, is filing it and rounding off that corner before the
> crack develops recommended? Has anyone ever seen one break catastrophically
> at this point?
I have been turning those, and only those, cranks for well over thirty years. None has failed.
However, at a shop, I have seen one with a starting hairline crack and heard (from friendly Jobst) that this might in fact happen more often than I could ever imagine.
Certainly a rounded corner is of benefit to prevent or to cure after.
Sergio
Pisa