How do I determine the thickness of an aluminum sheet?

To determine the thickness of an aluminum sheet, you can use a micrometer or a caliper, which are precise measuring tools. Place the sheet on a flat surface and measure from one side to the other at multiple points to account for any inconsistencies. Alternatively, you can use an ultrasonic thickness gauge, which is especially useful for non-contact measurements. For a quick estimate, a simple ruler can give you a rough idea, but for high precision, specialized tools are necessary. Always ensure the measuring device is calibrated and used correctly to get accurate results.