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WHITE METAL CLEAN UP. ??
#11
Before you do anything else , having cleaned up the journals, it would be worth having the crank crack tested .
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#12
Hi Roger, My confusion not white metal but the crank was reground and stored badly , now need to clean, various good suggestion.
Thanks all for your help.

Thanks, Peter will indeed now you mention.
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#13
Regrinding is expensive. Older repair manuals adopted all sorts of substitute finishing process's. With the ability to fit rods, with patience much is possible .But beware emery paper can remove a surprising amount of metal. A flat oilstone may prove useful. Not that abrasives/cutting compounds or must not be used on the white metal.
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#14
(21-01-2021, 01:55 PM)Rogerfrench Wrote: I am confused! In what way was the crank white metalled? White metal generally goes on connecting rods, not cranks.
Me too as well ?
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#15
I am wondering if yellow "Timesaver" lapping compound, which is designed for easing white metal bearings, and leaves no residual particles behind, would serve to both finish cleaning off the journal and to fit newly metalled rods? I have no experience of using this stuff, but have just got some in for another job.
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#16
I would clean the crank in a bath of Bilt Hamber rust removal, then crack test.
If ok then consider polish or regrind. If this is a proper Nippy engine I would only use 
38mm Phoenix crank. Wouldn’t risk a Nippy crankcase with old crank.
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#17
Acid based rust removers must not be used on stressed parts. i would be very wary of any compound used with white metal, except an old failing possibky rebored rod. In moderte use the oil films in old style bearings are much thicker than in high load high temp moderns and the superfine super round finishes are not so critical.
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#18
Sort of agree Bob, but rust pits are stress raisers, in many cases we are doing the best we can with 80 plus years old parts
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#19
Put the crank in the vice. Clean any rust of front and rear main 'journals' with brass wire brush only. You must not reduce the diameter here, particularly the rear - where a bit of rust might improve the bearing fit.

For the big end journals, cut a strip of fairly course cloth (denim is good) the same width as the journal, say 18inches long. Then use some sort of very mild abrasive (not carborundum) as a polish. I'm sure you get the idea. You will be surprised how abrasive the denim is by itself, so perhaps just try some light oil, paraffin/diesel as a lubricant first to see how you go. You simply need to do it so that you loose the high spots. I'd be less worried about small pits than some of the others on here. your fingers are your tools here, your fingertip can feel things that you cannot measure with a mic. When it feels smooth, it is smooth!

If the rag/oil doesnt work, then a kitchen cream cleaner, or a metal polish, Peek, autosol, brasso etc. I should tell you to work your way equally around the journal to ensure even ness, but frankly on a steel crank you are not going to be removing any diameter.

I need not tell you that after using an abrasive on the crank it needs a thorough clean, particularly the oilways.

A skilled fitter, starting with a file and finishing like this can make an oval journal round again. No machine tools needed.
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#20
Hedd, if denim is so abrasive, it's time for me to throw away my denim underpants.
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