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Dial Calipers - read the dial or the scale Take a look at the vernier calipers. See that bump on the bottom edge? That is a grip for your thumb. Slide it back towards the tail end of the calipers and the jaws open as shown on the dial calipers. If you are measuring the outer edge of an object, like, let's say the head of an ushabti figure, you would open the jaws of the calipers and slide them carefully over the head of the ushabti. Read the sliding scales along either top or bottom or read the dial to see the size of the head. Care must be taken to assure that your calipers are straight. Even a slight angle throws off your measurements. Remember this is highly precise work and readings must be taken very, very carefully to assure proper dimension and accurate drawings. Remember, it takes a lot longer to correct your work and find a mistake than to take the time to do it right the first time! Take a look at the top edge of the dial calipers. See those blade like edges sticking out the top? Those are to take measurements of the inside of holes like on the opening of a jar. Put them inside the opening and carefully spread them using the thumb grip. They will widen simultaneously as the jaws open. Be careful that you are taking your reading from the widest diameter (distance across). Bear in mind that hand made objects will have variance unlike the machine made objects of our time. Take several readings and make notes! Now look at the tail end of the dial calipers. See that little thing sticking out the bottom? As you move the thumb grip, simultaneously as the jaws open and the blades spread, that rod will move out the bottom. That is a depth gauge which you can put into a vessel and measure it's depth. Open the calipers until you hit bottom and take your reading. (this posting is the responsibility of the poster) |
n-jacobson@dfwind.com (Nola Jacobson) for more information. All emails will be forwarded to the poster's actual email address.
