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Grinding Operations
SELECTING GRINDING WHEELSGRINDING TIPS
Before using a grindingEfficient grinding is achieved by controlling!WARNING
wheel, be certain that itsthe pressure and keeping the angle between
maximum safe operating speed is notwheel and workpiece at 10! to 15!. If the
exceeded by the nameplate speed of thewheel is flat, the tool is difficult to control. If
grinder. Do not exceed the recommendedthe angle is too steep, the pressure is
wheel diameter.concentrated on a small area causing
burning to the work surface.
DISC GRINDING WHEELS
Grinding wheels should be carefully selectedExcessive or sudden pres-!WARNING
sure on the wheel will slow
in order to use the grinder most efficiently.
Wheels vary in type of abrasive, bond,grinding action and put dangerous stresses
on the wheel.
hardness, grit size and structure. The correct
type of wheel to use is determined by theWhen grinding with a new wheel be certain
job. Use disc grinding wheels for fastto grind while pulling tool backwards until
grinding of structural steel, heavy weldwheel becomes rounded on its edge. New
beads, steel casting, stainless steel andwheels have sharp corners which tend to
other ferrous metals.Obite� or cut into workpiece when pushing
forward.
Sanding Operations
SELECTING SANDING DISCjobs require the use of several grit sizes and
Sanding discs are made of extremely hardat times both Oopen coat and closed coat�
and sharp aluminum oxide grits, phenol-discs are required to get the job done faster.
resin bonded to a sturdy fiber backing forSee chart for application examples.
fast heavy-duty service and long life. TheOperation: Refinishing painted wood or metal surfaces.
discs vary as to size and spacing of the
REMARKSGRIT
abrasive grits. OPEN COAT (type H) N usedTo remove paint and to smoothCoarse
for soft materials and on paint or varnish.surface irregularities. 16-24-30
CLOSED COAT (type K) Nused for metal,To smoothMedium
hardwood, stone, marble and otherthe rough sanding. 36-50-80
materials.To remove scratches left by Fine
previous discs. 100-120
Sanding discs range in grit from 16 (very
To smooth surfaces for painting, Very Fine
coarse) to 180 (very fine). To obtain bestpolishing or waxing. 150-180
results, select sanding discs carefully. Many
SANDING TIPSstrokes. Be careful not to hold the sander in
For best results, tilt the Disc Sander at a 10!one spot too long. Do not use a circular
to 15! angle while sanding so that only aboutmotion, as this makes swirl marks. Test
1" of the surface around the edge of the discbefore use on scrap stock.
contacts the work.
Do not force or apply pressure when
If the disc (accessory) is heldsanding. Use only the weight of the tool for
!WARNING
flat or the back edge of thepressure. Excess pressure actually slows the
disc comes in contact with the work, atool down. If faster stock removal is desired,
violent thrust to the side may result.change to a coarser grit disc.
If sander is tilted too much, sanding actionRemove gummy paint from metal with an
will be too great and a rough cut surface orOopen coat� disc. Sand until sparks start to
gouging and snagging will result.appear, then stop and change to a Oclosed
Guide the Disc Sander with crosswisecoat� disc to remove any remaining paint.
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ACEC
CASIO
