1. Requirements for the use of hand saws
(1) When sawing, the saw blade can be lubricated and cooled. When sawing steel parts, some oil can be added to reduce the friction between the saw blade and the sawing section and cool the saw blade, which can improve the service life of the saw blade.
(2) The installation of the saw blade should be properly tightened, and the force should be even. The saw blade should be installed with proper tension. When sawing, do not suddenly swing too much or use too much force to prevent the saw blade from breaking off from the saw bow and hurting people during work.
(3) It is necessary to trim and polish the cracked teeth in time. When several teeth of the saw blade are partially cracked, they should be trimmed on the grinding machine in time, that is, the adjacent 2-3 teeth are ground into a concave arc, and the broken teeth are cut. Part polished. If not dealt with in time, the teeth behind the cracked teeth will crack one after another.
(4) When the workpiece is about to be sawed off, use a small amount of force. When the workpiece is to be sawed off, the pressure should be small to avoid the sudden disconnection of the workpiece due to excessive pressure and the accident caused by the hand rushing forward. Generally, when the workpiece is about to be sawed off, use your left hand to hold the broken part of the workpiece to avoid falling and hurting your feet.
(5) After sawing, the saw blade should be loosened and stored. After sawing, the tension nut of the saw bow should be loosened properly to remove the tension of the saw blade. But do not remove the saw blade, prevent the parts on the bow from falling apart, and store it properly.
1. The clamping of the workpiece is usually to firmly clamp the workpiece on the left side of the vise, and make the saw seam parallel about 20mm away from the side of the jaw to prevent deformation. The workpiece should generally be clamped on the left side of the bench vise for easy operation. The part of the workpiece extending out of the jaw should not be too long, and the saw seam should be about 20mm away from the side of the jaw, otherwise the workpiece will vibrate during sawing; The line should be kept parallel to the side of the jaw (the direction of the saw seam line and the vertical line should be consistent), so that it is convenient to control the saw seam and not deviate from the scribed line; the workpiece should be clamped firmly to avoid the workpiece moving or the saw blade breaking during sawing. At the same time, it is necessary to avoid deformation of the workpiece clamp and damage to the machined surface.
2. Hand saw grip method: The right hand is full of the saw handle, the left hand is in the shape of a tiger's mouth, the thumb is pressed against the back of the saw beam, and the other four fingers are lightly supported on the front of the saw bow.
3. Stand naturally with two legs, and the center of gravity of the body is slightly on the back foot. The body and the center line of the vise are roughly at a 45° angle, and lean forward slightly; the left foot is half a step forward (the distance between the back roots of the left and right feet is about 250-300mm), the sole of the foot and the vise are at a 30° angle, and the knee is at an angle of 30°. Slightly bend, keep it natural; the right foot should stand firm and straight, do not use too much force, the sole of the foot and the vise form a 75° angle; the line of sight should fall on the cutting part of the workpiece.
4. When the saw is pushed, the upper part of the body leans forward slightly, giving the hand saw appropriate pressure to complete the sawing. When pulling the saw without cutting, the saw should be lifted slightly to reduce the wear of the saw teeth. When pushing the saw, the thrust and pressure are controlled by the right hand, and the left hand hardly applies pressure, which mainly cooperates with the right hand to straighten the saw bow.
When the hand saw is pushed out, it is the cutting stroke, and pressure should be applied. When the hand saw returns to the stroke, all teeth do not participate in cutting, but only pull back naturally without applying pressure to avoid tooth wear. The workpiece is about to be sawed off with less pressure.