Grinders and polishers are tools that cut or abrade work-pieces and materials to alter them or make them look better. Grinders cut, sharpen, shape, and grind materials. Polishers buff, smooth, and shine the surface of materials. These tools can be used on metal, stone, plastics, wood and others. In some cases, the functionality of these tools has been extended to include the sanding feature. Depending on your needs, the sander/grinder and the sander/polisher can be a useful addition to your array of tools.
Depending on the materials the grinding disc is made of, the grinder can achieve various levels of abrasion. Synthetic diamonds are the most abrasive; silicon carbide is less abrasive, even though it can cut through very hard materials. The choice of the disc depends on how often you’ll use it or on what you’ll be using it. Grinders and polishers are listed with the largest diameter of the disc which they can accommodate. When selecting a disc, it’s important to check the arbor size (the metal knob to which the grinding disc is attached and held in place) to make sure that the grinding disc will fit the grinder.
Benchtop Grinder:(Also, bench grinder) These grinders provide excellent grinding, shaping, buffing, and sharpening action to metal tools, pipes, wood, and stone. Because they’re situated securely atop a work bench, more stability and precision can be attained in these various projects. Bench grinders use thicker and larger grinding discs for each of these purposes. Bench grinders complete the task of smoothing out rough spots, de-burring pieces, and polishing them to perfection. The motors on these machines are made to handle frequent and heavy use.
Angle Grinder: Angle grinders are handheld tools that remove or grind off surface materials from pipes, wood, or stone and/or cut directly into those materials. They’re a convenient alternative as angle grinders can be used on pieces that are bigger or heavier than what a bench grinder can accommodate. Angle grinders are separated into two categories based on the largest disc they hold. The disc size for small angle grinders is usually less than 7 inches; for large angle grinders, it’s usually greater than 7 inches.
Straight Grinder: This grinder acts like a smaller and portable version of the benchtop grinder. It can accommodate similar wheels that a benchtop grinder uses but the disc diameter is usually limited to less than 5 inches. Varying thickness of the grinding discs can be used for activities such as cutting, shaping, or deburring. These also work well on metal dies.
Die Grinder:Much smaller than either of the previously listed grinders, the die grinder is for use with shaping or polishing the insides of round, metallic objects like pipes or parts for plumbing. They can reach where other tools can’t. On die-cast models, the grinder removes metal pieces for a more exact fit of the die. Die grinders are suited to higher rpm with less torque for their applications.
Buffers and polishers create a better, more visually-pleasing appearance in things like wood, metal, and stone. Lower rpm and the polishing or buffing pads with which they are used make these tools largely beneficial to architectural projects or auto-body shops—among many others. Polishers are more abrasive than buffers and can remove rust from metal or make sanitary the insides of pipes or plumbing. In the polishing process, different levels of abrasion—and usually a wax or lubricant—create the desired finish on metal or wood pieces. Buffing creates a beautiful finish and is part of the polishing process although to an even lesser degree in terms of abrasion.
Being a Smooth (and Safe) Operator
Because of the high speed of the moving hard disc and the materials into which they cut, grinders pose some safety concerns. As it goes with all tools, proper operation of the grinder can greatly limit the likelihood of injury. This means taking a few precautionary steps before and while you’re using the grinder to ensure safety.
Since bits and shavings of metal, stone, wood and the like can get into your eyes during grinding, proper eyewear is necessary. And, since the decibel level when using the grinder is very high, proper ear protection is greatly encouraged. When using the grinder, thick gloves also come in handy since the spinning disc can be dangerous to uncovered appendages. Additionally, dust masks should also be worn to reduce the amount of particulate you might inhale.
On the disc itself is listed the maximum RPM (Rotations Per Minute), and the disc shouldn’t be made to work outside these listings. For example, if the grinder can operate at speeds of 9000 rpm, you shouldn’t use a disc with a maximum rpm of 5000. Otherwise, the disc can shred and damage the grinder itself. This, in turn, might create hazards to you. Grinders can be immensely helpful tools; remember to be careful and responsible.
Grinders and polishers help refine pieces or make them look better. At ToolsDirect.com, we offer the industry’s best brands, so achieving that professional look you’ve wanted in your projects can be done efficiently and affordably. If you need help choosing the grinder that’s right for you, give us a call and our knowledgeable customer service representatives will be more than happy to assist you.