From time to time you need to sharpen the cutting element of the circular saw. Sharpening circular saw requires certain knowledge, special equipment. There are machines designed for this purpose.
Types
Machines for sharpening circular saws - a group of devices for resuming the sharpness of cutting elements. Depending on the functional features, they are:
- Automatic. Units are installed at large enterprises.
- Semi-automatic, mechanical (tools for sharpening cutters manually). They are characterized by low productivity, mainly used in home workshops.
When sharpening chains for longitudinal sawing, other devices are used that can sharpen each tooth with files.
All equipment, including an electric drive, is similar in principle to operation. Only performance is different. So, low-power household samples can continuously function up to 20 minutes. After they must be turned off at the same time for cooling.
Professional tools can work up to 8 hours. They only need a few short breaks of 20-30 minutes. Some units have an abrasive wheel for sharpening, a sanding belt of a similar action.
In most cases, the saw tool can be sharpened on machines, the main element of which is the grinding disc. Belt devices are more suitable for industrial use with large volumes of fine grinding.
Sharpening machines are completed with the circles differing:
- thickness - 16–40 mm;
- outer diameter - 12–250 mm;
- mounting hole - 12.7.16, 20, 32 mm;
- material of manufacture.
Pay special attention to what the abrasive is made of: the result of work depends on the quality. In addition to conventional cutters, there are circles on which there is reinforcing soldering - a plate of hard alloys. Most often there are corundum, diamond circles. They are good at sharpening carbide tipped discs designed for cutting extremely hard materials.
The wheel for installation must be purchased taking into account the characteristics of circular saws. The abrasive tape is selected in accordance with the dimensions of the machines. Granularity, which affects the nature of grinding, is also taken into account.
How to sharpen
The abrasive disk is cleaned of dirt, residues of the removed material, set the angle of inclination. Sharpening starts from the front of the tooth. The maximum allowable metal layer for removal is up to 0.20 mm.
It is necessary to ensure the correct supply of the cutting element to the grinding wheel. The grinding wheel should be in full contact with the abrasive. In the process, it is necessary to ensure that the blade does not overheat. You can avoid raising the temperature of the material to critical levels by adjusting the speed of rotation of the abrasive element, wetting it with a small amount of water before work.
Diamond coated wheels processing a win-cutting cutting tool are usually cooled with a special fluid (coolant). The process can be considered completed after the appearance of a uniform burr along the entire surface of the edge of the blade. Final grinding is performed manually.
It must be remembered that the machine can only process a workpiece in one plane at a time.
It's important to know
The main wear of the saw falls on the upper edge of the teeth. It is most in contact with the processed material. Due to constant contact with hard surfaces, rounding of its central face can reach 0.3 mm. This is a critical indicator. It is necessary to ensure that the central protrusion is rounded by no more than 0.2 mm, otherwise it will be difficult to sharpen the element well, it will take a lot of time.
The degree of wear is usually determined by the condition of the teeth, the quality of the cut. Each blade has a resource. In most cases, this is 30–35 sharpenings.
It is impossible to prevent the formation on the cutting edge during its processing with the help of machine tools notches, chips, other defects that violate the integrity of the metal.
Build a homemade sharpener
The manufacture of a home-made grinding machine is resorted to when there is no factory equipment at hand, and the cutting wheels have to be sharpened periodically. On the device, you can sharpen a dull circular saw blade.
To build, you will need:
- electric drive
- caliper
- inclined mechanism
- screw limiters.
The circle must be fixed on the engine. The disk web is installed on the support, while screw stops provide the torch to move along the axis of the circle, creating the necessary angle of inclination. Proper fixation of the saw blade relative to the abrasive is the main requirement for sharpening. In order for the angles to be observed, an adjustable stand is required, fixed in the same plane with the circle on the device frame. When installing the disk on the stand, you need to ensure that the teeth are placed perpendicular to the plane of the machine.
When self-assembling a device for sharpening circular saws, it is recommended to use drawings and diagrams.
Sharpening can also be performed with mechanical devices. But when using special units, the operating time is reduced, the sharpened cutter will have a sharper edge.