Regrind crank or not?
Posted: Fri Dec 24, 2021 8:24 am
Hi,
I have two cranks, and I'm deliberating which one to use and which one to sell. There isn't much to choose between them; both are dimensionally ok - not oval or tapered to within half a thou - but there us some slight scoring.
The best one has some slight visible scoring on one or two journals that I can barely feel with my fingers. Do you think this will be ok to use - I don't have a camera so couldn't put a picture up? It's so slight I think it would polish out with a strip of rag and some fine valve grinding paste. I don't believe in grinding a crank when it's not needed.
The other crank has one or two deeper scores that I can feel with my finger nail around the whole circumference so I've dismissed it on that basis
I have two cranks, and I'm deliberating which one to use and which one to sell. There isn't much to choose between them; both are dimensionally ok - not oval or tapered to within half a thou - but there us some slight scoring.
The best one has some slight visible scoring on one or two journals that I can barely feel with my fingers. Do you think this will be ok to use - I don't have a camera so couldn't put a picture up? It's so slight I think it would polish out with a strip of rag and some fine valve grinding paste. I don't believe in grinding a crank when it's not needed.
The other crank has one or two deeper scores that I can feel with my finger nail around the whole circumference so I've dismissed it on that basis
.Its surprising just how small a gouge you can "finger nail " .....might only be a thou or so . I would get a bit of 800-1000 grit wet and dry sand paper ,cut a strip as wide as the journal , squirt of crc wd40 what ev , put the crank in the upturned block and rotate it ( helper may be req) and apply sandpaper to journal. If its a main just leave the shell out and slip the sandpaper in behind journal . If the marks dont polish out by the time the rest of the journal is showing signs of the polishing give up and grind it.