How to Measure Bores in Aluminum Castings
- 1). Place the internal caliper jaws inside the bore. If your caliper has a thumb screw to prevent sliding action to preserve a measurement, loosen it so the caliper jaws can later be adjusted freely.
- 2). Adjust the caliper jaws to the bore diameter. The jaws should lightly touch the walls of the bore.
- 3). Remove the caliper from the bored feature. Tighten the thumb screw to preserve the measurement. Obtain the reading from the caliper to determine the diameter of the bore per the instructions supplied with your specific type of caliper.
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