In the jewelry production process, whether the jewelry craftsmanship is qualified or not can be judged only after measuring with a measuring tool. The correctness of the indicating value of the measuring tool is directly related to the correctness of the qualification of the jewelry product. Here is a brief description of several measuring tools that will be used in the jewelry crafting process.

1. Vernier caliper

In order to improve the reading accuracy, the scale value on the ruler must be as small as possible. This requires a dense scale and a thin width of the engraved line. This is not only difficult in manufacturing, but also difficult to observe with the naked eye during use. If you put a ruler with a thicker scale value side-to-side together, there will be a slight error between the marking lines using them, which can be immediately seen. The vernier caliper is to use this feature, add a scaled vernier ruler to the main ruler of the scribing line for reading,

Each scale of the main ruler is 1mm. Each scale of the cursor is 0.98mm. When in use, the main ruler reads as an integer, and the cursor reads as a decimal (<1mm), and the sum of the two is the actual size.

2. Outside micrometer

The outside micrometer is made by the principle of threaded transmission. When threaded transmission, the stroke in the axial direction is proportional to the thread rotation angle. The thread pitch is generally made 0.5mm, and there are 50 divisions on the circumference of the microtube, and the axis of the wire rod moves 0.01mm for each rotation. When the micrometer is reading, the measuring axis is engraved as an integer (>1mm), and the decimal is read on the micrometer. The sum of the two is the actual size. The actual reading is shown in the figure, and the reading is 14.10mm.

Three, digital caliper

A digital caliper is a length measuring instrument that uses a capacitive grating (or grating, etc.) measuring system and a digital display for reading. The appearance is shown in the figure, and it is mainly used to measure the outer and inner dimensions of the workpiece.

1—Inner measuring claw of the knife edge; 2—Range frame; 3—Brake screw; 4—Display; 5—Data output port; 6—Rule body; 7—Outer measuring claw; Zero button; 10-depth gauge.

Four, with a caliper

The appearance of the caliper with a meter is shown in the figure. The distance between the two measuring jaws of the caliper after relative movement, the integer part of the millimeter value is indicated on the ruler, and the decimal part of the millimeter value is indicated on the indicator. Calipers with a meter are mainly used to measure the outer and inner dimensions of parts.