BM 2610007691 12-09:BM 2610007691 11-09 12/18/09 11:17 AM Page 13
Grinding Operations
SELECTING GRINDING WHEELS Before using a grinding wheel, be certain that its maximum
safe operating speed is not exceeded by the nameplate speed of the grinder. Do not exceed the recommended wheel diameter.
DISC GRINDING WHEELS
Grinding wheels should be carefully selected in order to use the grinder most efficiently. Wheels vary in type of abrasive, bond, hardness, grit size and structure. The correct type of wheel to use is determined by the job. Use disc grinding wheels for fast grinding of structural steel, heavy weld beads, steel casting, stainless steel and other ferrous metals.
GRINDING TIPS
Efficient grinding is achieved by controlling the pressure and keeping the angle between wheel and workpiece at 10° to 15°. If the wheel is flat, the tool is difficult to control. If the angle is too steep, the pressure is concentrated on a small area causing burning to the work surface.
Excessive or sudden pres- ! WARNING sure on the wheel will slow
grinding action and put dangerous stresses on the wheel.
When grinding with a new wheel be certain to grind while pulling tool backwards until wheel becomes rounded on its edge. New wheels have sharp corners which tend to “bite” or cut into workpiece when pushing forward.
CUTTING METAL
Using the optional type 1A wheel guard, it is possible to perform limited cutting on small stock such as metal tubes, piping or rebar. When cutting, work with moderate feed, adapted to the material being cut. Do not exert side pressure onto the cutting disc, tilt or oscillate the tool. When cutting profiles and square bar, it is best to start at the smallest cross section.
Always follow precautions for kickback.
Do not apply side pressure to cutting wheel to reduce wheel speed.
Use silicone oxide wheel.
The tool should always be used so that sparks are directed away from user.
Sanding Operations
SELECTING SANDING DISC Sanding discs are made of extremely hard and sharp aluminum oxide grits,
Sanding discs range in grit from 16 (very coarse) to 180 (very fine). To obtain best results, select sanding discs carefully. Many jobs require the use of several grit sizes and
at times both “open coat and closed coat” discs are required to get the job done faster. See chart for application examples.
Operation: Refinishing painted wood or metal surfaces.
REMARKS | GRIT |
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To remove paint and to smooth | Coarse |
surface irregularities. | |
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To smooth | Medium |
the rough sanding. | |
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To remove scratches left by | Fine |
previous discs. | |
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To smooth surfaces for painting, | Very Fine |
polishing or waxing. | |
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