Band saw blade: It consists of a hard sharp-toothed saw blade taut on the frame, and is used for cutting metal and other molding materials. The band saw blade will become dull after being used for a period of time, resulting in unsmooth cutting, and the cutting surface formed on the workpiece is very rough and irregular, so it is necessary to polish the sawtooth. Method 1: Use the special band saw blade grinder S380 from America and Japan to grind the band saw blade. Just buy a special band saw grinder, pay attention to choose according to the types you usually grind, and learn the operation method of the band saw grinder, which will make it easier to work. For example, there are various types of gear grinding machines with saw blades in the United States and Japan. Method 2: Take it to the tool grinding shop for grinding. This method is more suitable for people who have high requirements for polishing and don't polish frequently, but the cost of polishing varies from tens of yuan each time, which is higher. But in some small cities or counties, there is no business place for grinding woodworking tools, so the blunt band saw blade can only be ground by itself. Method 3: File the band saw blade flat with a file, or polish it with an angle grinder or a small grinding wheel. It is inefficient to file the sawtooth with a file, and the integrity of the curve between the front angle of the sawtooth and the tooth root can not be guaranteed. The band saw blade is prone to produce a gap with concentrated stress somewhere. In this case, the band saw blade is easy to break in use. Although it is efficient to grind sawtooth with angle grinder, it is easy to grind sawtooth because it is difficult to operate accurately. It is relatively easy to grind the band saw blade with a small mill, but it is also easy to accidentally injure the sawtooth other than the target tooth. So this is a difficult thing that many wooden friends often encounter in DIY practice. Here I introduce a relatively easy operation. How to easily sharpen a fast band saw blade? 1- According to the type of saw blade, simply measure the curve size of sawtooth shape, and buy a small corundum grinding head with a size suitable for the curve shape of saw blade from the shop selling die parts and tools. The diameter of the grinding head is usually between 3 mm and 6 mm. The shape of grinding head can only be purchased in the form of cylinder or brush head. Put a small grinding head with suitable sawtooth shape on the belt. Only buy a small corundum grinding head suitable for naturally grinding the shape curve of sawing tools. The hardness of the grinding head should be the hardest. This kind of small grinding head is very cheap and has several corners. 2- Clamp the sawtooth of the blunt band saw blade horizontally upward on the fixture, and check the sawing situation to see if it is necessary to carry out sawing correction. If sawing correction is needed, use a saw clamp to make corresponding correction and tooth shifting. After checking and correcting the sawing, grind again. 3- Install a suitable small grinding head on an adjustable hand electric drill or small electric mill (hand-held pen engraving machine, rotating speed 654.38+ 100000, or higher). Turn the speed of the hand drill to the highest (also thousands of revolutions), and the small electric mill will be adjusted to 3000 or 4000 revolutions. Put the grinding head. And gently move the grinding head back and forth several times, naturally you can grind very sharp serrations. Grinding one tooth at a time and sitting on a stool 1 hour can grind 1 very sharp band saw blades. In the process of grinding, the strength should not be too great, and the grinding time of each tooth should not be too long. Prevent the sawtooth from being worn or annealed due to excessive grinding. It usually takes 3 to 5 seconds to grind the sawtooth. Observe the grinding at any time. According to the sawing situation, the tooth shifting direction of each saw tooth and the axis of the grinding head should also have a certain deviation angle from the general direction of the saw blade, so as to grind sharp sides and make the cutting edge of each saw tooth of the whole band saw blade sharp in both directions. Only in this way can the cutting surface of the band saw blade be smooth. When grinding each sawtooth in different directions, the deviation angle between the axial direction of grinding head and the general direction of band saw blade should not be reversed. Otherwise, if the deviation angle is reversed, the original side edge on the sawtooth will be more blunt. This deviation from the angle direction must be understood with your heart. It's best to find a small piece of waste band saw blade for trial grinding, and then put it on a good band saw blade for grinding.