dial bore gauge

Say I have a mitutoyo dial bore gauge and I want to measure bores for journal oil clearance, taper, roundness etc, what is the preferred method to calibrate the gauge with?

I have looked over the internet and there seems to be three main options, master ring gauges, block gauges and using an external micrometer/caliper. Given the accuracy isn't quite that of what is used in aviation, what would be the most realistic and accurate option for the cost in calibrating as I don't quite have the money to spend on many master ring gauges. I also don't understand how a block gauge calibrates an anvil, as I have looked everywhere and people say they calibrate with a block gauge and it doesn't make sense as to how they calibrate it, yet the micrometer/caliper method and the master ring gauge makes sense.

Please enlighten me as to the best method to accurately calibrate bores and cylinders in cars with the dial bore micrometer.

use ext micrometer abt $100-150 for a good one 0.0001"

laser is the next step up in precision but probs 100x more expensive

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Originally Posted by subaerzwar

Say I have a mitutoyo dial bore gauge and I want to measure bores for journal oil clearance, taper, roundness etc, what is the preferred method to calibrate the gauge with?

I have looked over the internet and there seems to be three main options, master ring gauges, block gauges and using an external micrometer/caliper. Given the accuracy isn't quite that of what is used in aviation, what would be the most realistic and accurate option for the cost in calibrating as I don't quite have the money to spend on many master ring gauges. I also don't understand how a block gauge calibrates an anvil, as I have looked everywhere and people say they calibrate with a block gauge and it doesn't make sense as to how they calibrate it, yet the micrometer/caliper method and the master ring gauge makes sense.

Please enlighten me as to the best method to accurately calibrate bores and cylinders in cars with the dial bore micrometer.

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I think you're trying to do something that a dial bore gauge is not used for. You use a dial bore gauge to check for concentricity, not absolute values. For example, when honing a block, you use a dial bore gauge to check for bore taper, barreling, egging etc. by setting a "zero" and then looking for deviation from that zero at various points in the bore. To find the actual measurement of the bore, you use an inside micrometer, i.e. "adjustable stick" which is then checked against a standard micrometer. An external, standard type micrometer is more accurate than an inside mic.