The importance of measuring bell housing runout.

There's no substitute for experience and over the past week I've scaled the learning curve and its finally beginning to flattened out. Back to the task at hand:
Greg took the initiative to drop one of his 440's onto a cart so we could compare runouts. The cast iron bell had almost zero runout, matching the results we measured on the Coronet.
Next, we mounted the SST bell to his block and using his dial indicator, measured .0445" TIR / .022" runout.
Then we remounted the SST bell to the Coronet, and using my indicator measured .045 / .0225. Success!
The bell bore is still far from concentric, but the runout is correctible with .021" offset dowels.
Shop 440, SST bell
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Close up
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SST bell in the Coronet
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Close up
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