Grinders and Attachments

Table of Contents

1. Start Here
   1. Types of Grinders and attachments
   2. Angle grinders and attachments
   3. Miller cutter
   4. Safety precautions
   5. Guards
   6. Operating grinders, sanders and wire wheels
   7. Removing and replacing discs and accessories

Types of Grinders and attachments

Grinding machines can be broadly classified as either portable or fixed.
In this section emphasis is given to angle grinders as portable grinders, and to the pedestal type of fixed grinders. Sanding discs, used to obtain a smooth surface preparation, are mounted on a rubber or plastic backing plate attached to an angle grinder.
Wire brushing attachments are usually cup shaped or flat and they are often used as a grinder attachment for cleaning surfaces of impurities such as paint and oxides.

Miller cutter blades are used extensively in the Aluminium fabrication industry for cutting alloy sections and plate. These blades when used in conjunction with an angle grinder can be extremely dangerous if they are used incorrectly.

Some portable grinders are illustrated here.

Die Grinders	These machines are designed to use grinding points up to 25 mm in diameter and have a no-load speed of around 27,000 revolutions per minute. The grinding points are held by a collet.
Air-Driven Die Grinder	These machines are sometimes called pencil grinders. This machine uses grinding points up to 8 mm diameter and has a free running speed of 80,000-100,000 rpm.
A Straight Portable Grinder	Commonly referred to as Barrel Grinders and most often used to grind inside cylinders. This machine uses wheels up to 125 mm diameter and has a no-load speed of 6,800 rpm.
Electric Angle Grinders	These machines are available in a range of sizes from 4' up to 9" (100mm-230mm) and have free running speeds of up to approximately 10,000 rpm. They are the most commonly used grinding tool in Metal Fabrication. Power varies according to size but as a guide ranges between 750 to 2,500 watts for industrial-type machines.
Bench or Pedestal Grinder	Bench Grinders like the one shown here are commonly used for maintaining and sharpening tools, sharpening and restoring electrodes for TIG welding, or grinding small work pieces. This one has a 150mm wheel and operates without any load at around 3,000 rpm.
Air-Driven Angle Grinders	Air driven machines are often used in areas where electricity could prove to be too risky to the operators. The grinding disc diameter is 180 mm and the free running speed is around 8,500 rpm.