Grinders: What Varieties Are Available?
Grinders are powerful tools suitable for cutting brick, concrete and metal. However, there are various types of grinder which are used for different jobs, so choose carefully – this is definitely not a one-size-fits-all solution to your heavy-duty cutting needs. All grinders will throw off a lot of sparks and particles, so eyewear, protective clothing and probably ear-defenders are a good idea.
Angles, bench and die
Angle-grinders spin a circular disk at high speed, which can be used to cut through even tough materials quickly and efficiently. They aren’t super-accurate, but they’ll get the job done with a minimum of fuss (provided you keep your hands clear of the blade). They generally also have attachments for sanding and brushing surfaces.
Bench grinders are broader spinning disks mounted on a fixed stand. They are useful for sharpening metal tools such as chisels, or creating a point or edge on a knife. They may be water-cooled to prevent overheating and oxidization of the metal, which can blunt the tool.
Die grinders use a grinding ‘nose’ to bore and smooth the inside of cylindrical objects like pipes, removing sharp edges and burrs. They may be hand-held or bench-mounted.
The need for speed
Grinders can be powered by electric or petrol motors, or even compressed air. It’s worth checking the speed and power of the grinder you’re buying as this will affect what you can use it for.
Generally speaking, pneumatic grinders are smaller and lighter, and are more suitable for precision jobs, whereas electric grinders are more commonly used for heavier work. Grinders with larger disks have correspondingly faster edge speeds. High-speed grinders are better at cutting tough materials like metal and concrete; lower rpm’s are better for softer materials such as plastic, and for achieving a neater finish.
Pic credit: http://www.flickr.com/photos/jopoe/
