Crank polishing

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barracudadave67

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Polished the crank for my 360 build today.
Got tired of it rolling around when i tried to polish it, so i made a stand. works good. no more rolling around.
Try it, you'l like it.
Dave

20200512_144623.jpg
 
Right back at you barracudadave67, built a 2 leg crank holder like you have there, and a Vinegar Dunk Tank too.

Had a buddy rotating the crankshaft on the wood stand while polishing with emery cloth and then final polish with Crocus Cloth. Just like new.

Thanks for your post.

360 Crank Before:
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Final Polished 360 Crank
20200512_222131.jpg
 
Right back at you barracudadave67, built a 2 leg crank holder like you have there, and a Vinegar Dunk Tank too.

Had a buddy rotating the crankshaft on the wood stand while polishing with emery cloth and then final polish with Crocus Cloth. Just like new.

Thanks for your post.

360 Crank Before:
View attachment 1715527083
View attachment 1715527084
View attachment 1715527085
View attachment 1715527086

Final Polished 360 Crank
View attachment 1715527087
Looks good. Wish I had a buddy to help polish my crank. :D
 
That's all Vinegar? Wow, my forged Eagle crank is a little dull after being out of the block for 3 months. will have to dunk it.. How long?
 
That's all Vinegar? Wow, my forged Eagle crank is a little dull after being out of the block for 3 months. will have to dunk it.. How long?

Just straight 6% cleaning vinegar from the grocery store.

Submerge in the dunk tank overnight for 12 hours. Can polish up the counter weights with a scotch brite and some WD-40 at the end, shines and protects.

Degrease the crank with brake parts cleaner or solvent before doing the vinegar dunk so it is clean of oil. Then you can pour the used vinegar back into the jugs to save for the next clean up project.

Just a word of caution for those doing this for the first time. You want to stay off the knurling at the rear main seal area, that is what helps push the oil back into the engine at the seal area.

Good Luck
 
I believe you'll ruin the crank polishing it stationary. It should be spinning while using a crank polisher. Your not polishing your shoes.
 
I believe you'll ruin the crank polishing it stationary. It should be spinning while using a crank polisher. Your not polishing your shoes.


If you look in his first picture on the floor I’m pretty sure that is a leather shoestring. In the right hands you can do a damn nice job of touching up a crankshaft
 
Yes that is correct. Thats my shoe string, and one of the crocus cloth strips I used. The crank is in good shape. There were a few "fingernail marks" on it. That is why I did the hand polising thing. Crocus cloth is good for that.
If it would have needed grind polishing, I would have done that. This engine is a "budget build".
Dave
 
Where do you get the Crocus Cloth and what grit is it?
Do you start with a 400 grit Emory Cloth? or is that too aggressive?
I built a two-leg stand for my bench today.
Time to start cleaning!

Crank Stand.jpg
 
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that vinegar dip is the ****. Ill make something up tonight. I dug a pit and lined it with a trash bag the last time. It didnt do much but I didnt degrease it either before I dunked it or follow up with scotchbrite to the throws. There is a way to rig up a drill and pulley on a bow and let the crocus belt fall onto the journals while you are turning the crank by hand. It may be a little aggressive unless your using 1500 grit.
 
Leather Boot laces .
Wrap the "cloth" around the journal, then a couple wraps of the lace around the outside, pull alternate ends of the lace .
I lay the crank in the solvent tank, and flow clean solvent over the journal as I polish it
 
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This large belt fixture standing up on this lathe is for polishing cranks. Your arms would fall off using that leather shoe string method after a couple journals.

They not only must be smoothe they must be concentric, flat, and round, And every journal must be the exactly same

My grand pop did a old briggs single when I was younger with the string and crocus cloth method. I got tired just watching and went in the house. I remember my Grams rubbing some stinky ointment on his arms afterwards.

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320 wet dry
240 wet dry
final polish with Crocus Cloth
(all by hand)

WD-40 works great to rinse the wet dry paper and journals clean.

Easy Peasy 1 2 3
 
whats a place get to polish a crank nowadays? Those Subie cranks look like jewelry!
 
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