I decided to try some home crankshaft polishing today. Many car guys know about using very fine wet/dry sandpaper with light oil or WD40 to polish up an imperfect crank journal. My cast 225 crank wasn't too beat up, but I used 3000 grit sandpaper to knock down any high spots before measuring the crank journals. But I wasn't too thrilled with the resulting surface appearance. I watched some crank polishing videos on YouTube and saw one of a guy using Simichrome metal polish on a shoelace and thought that might do. Except that I don't have any liquid metal polish. So I tried some paint buffing compound, but that accomplished nothing. Then I went into my metal polishing supplies and got out the bar of emery compound. This is meant for a buffing wheel so I melted a small area on the back of the bar and used the melted compound to coat my shoelace. I then applied some WD40 to a crank journal and polished it with my newly abrasive shoelace. Things started looking pretty good! I even tried following up with a finer compound, but I don't think it did a thing.

_________________
Joshua

3000 grit is really too fine.

I'd start with 600 then go to 800 or maybe 1200.

When doing it by hand, you'd need to go crazy to remove too much metal even with 600

Greg,

I think you're correct. I also worked on the forged crank for the aluminum block and it has more scratches than the cast crank pictured so I'll go back to it probably with 600 initially. The journals are so wide on the forged crank I want something wider than a flat show lace. I'll see if I can't score 6' of pull tape from the electricians. That stuff is twice as wide.

_________________
Joshua