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Tue Jan 27, 2015 9:14 pm

I made a few marks on my crank. What are you guys using to polish journals?

Wed Jan 28, 2015 12:50 am

Scotch brite. First dry, then with soapy water for a better finish.. Just make sure to dry it off after you're done, and put on some oil, so it won't rust. Worked wonders on my crank. :)

Here's how mine turned out after a little bit of work..

Wed Jan 28, 2015 1:45 am

Crank polishing belts

Wed Jan 28, 2015 4:18 am

I use micro-finishing tapes.

Scotch-Brite is not going to do anything for journals. If you scratched it, then a micro-finish tape will de-burr that. Otherwise, that little burr will eat the bearing surface.

Wed Jan 28, 2015 6:36 am

Sounds like u let rod bolt bang against crank journal, put short pieces of hose on them &u wont do this.

Wed Jan 28, 2015 6:51 am

Polish with ultra fine carborundum paper (1500) and test with fingernail, if mark goes away of if you can not hook fingernail in scratch or mark, you are probably good....

Dale

Wed Jan 28, 2015 8:28 am

modok wrote: Crank polishing belts

Me too!! Plus a Storm Vulcan Crank Grinder....

Wed Jan 28, 2015 9:27 am

Wasn't the rod bolts. It was something stupid I did, micrometer had an edge. Guess I'll take it in to have it polished. How much is usually taken off with a polish?

Wed Jan 28, 2015 9:49 am

jason wrote: Wasn't the rod bolts. It was something stupid I did, micrometer had an edge. Guess I'll take it in to have it polished. How much is usually taken off with a polish?

It depends. If I just want it to shine and be smooth, I will use a worn belt. If I need to take off a scratch, I'll use a a brand new belt. Just depends on how long you polish it for.

Wed Jan 28, 2015 11:28 am

like roy said depends on how much it effed it. I have stoned some of them with jhu800 then polished by hand with 600-800 wet cut into strips&wide shoe string raped around 3 times.(wet of corse)

Wed Jan 28, 2015 4:43 pm

x2 on the micro finishing tape.

Wed Jan 28, 2015 5:55 pm

If it just has a nick in it then don't need to polish the whole thing.
First use a stone, or abrasive paper backed up with a flat piece of metal,, and use that to carefully go over the area and take off any high spots. Then just polish it with a piece of 400 on your thumb, and it's fixed. Move the direction as if the crank was rotating like it does in the engine when polishing. You can still see the scratch but consider how small it is. The amount of bearing area you have lost is very small, the other 99.9% of the journal is fine so it will work great,

Most crank polishing belts for fiddle polishers are 320 grit, but we never FINISH with a fresh belt. finish use a OLD belt and your pretty much burnishing it as much as removing material. You can remove anywhere from .0002 to .001 but beyond that hard to avoid taper.

There is a scotchbrite type polishing belt. IMO the scotchbrite stuff only helps blend in the imperfections which fools the eye but not the bearings, but for some that is what they want.

Wed Jan 28, 2015 9:48 pm

Machine shop said they can polish it, $25. I'll let them do it so I don't mess it up more.