Machining issues.

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1963dartgt

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Long story short got my crank ground .030 .030.
Got 4092m 030 bearings and the machine shop says the cranks ground for the bearing but the part where the bearings sit isnt right. Im posting up some numbers maybe you guys could help me out with what i should do. He suggested .020 bearings, grinding the crank to fit or get a new block and start over again. Thanks

20200724_110211.jpg
 
Is your crank steel? Is your crank cast? 5070m's to be used with a cast crank having a bearing width of .8815 for positions 1,2 and 4 and 1.108 for the thrust.
4092m's to be used with the steel crank with a bearing width of 1.039 for positions 1,2 and 4 and 1.255 width for the thrust.
Are you sure "HE" suggested using .020 bearings on a .030 crank? THAT is stupid.
 
No steel crank and yes he suggested the bearings which i didnt think will work since the clearence is only .001 not .010
 
So i went and picked up my motor from the first machine shop. Got a little loud there I kinda feel bad i usually dont like to cause a scene but after almost 5 months and **** still wasnt right I was a little upset.He refunded the price of the crank grind and bearings which were still in new shape(~$200). Drove the 100 miles one way to the next machine guy who runs out of his garage. I told him my story and he laughed alot. Told me to grab a beer and have a seat. The dude tied up his beard,light a cigar and got to work. About 30 min later everything was perfect with .002 clearance on everything. Asked what i owed him he said the story was good enough and i just need to pass it on. Still some damn good people in the world i suppose.
 
I like your "new" machine shop guy! Good to hear that he knows how to run a crank grinder. Curiosity, ask what make of a grinder he has. Mine is a Schou.
 
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