How to use the level ruler
A general level has three glass tubes, each with an air bubble.
Put the spirit level on the object to be measured, which side the bubble of the spirit level is inclined to means that that side is higher, that is, the height of the side needs to be lowered, or the height of the opposite side needs to be increased, and the bubble is adjusted to the center, which means that the measurement is carried out. The object is horizontal in that direction.
In principle, the horizontal and vertical are in the center, and the angled blisters are naturally in the center.
The horizontal glass tube is used to measure the horizontal plane, the vertical glass tube is used to measure the vertical plane, and the other is generally used to measure a 45-degree angle. The functions of the three blisters are used to measure whether the measurement surface is horizontal, and the blisters are centered. If the bubble is off-center, the plane is not horizontal.
In addition, according to the principle of determining a plane by two intersecting lines, it is necessary to measure two non-parallel positions in the same plane to determine the level of the plane.
