Struers Discotom-2, Instruction Manual

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Discotom-2
Instruction Manual
11
Open the left-hand side door (fig. 2.13), take the spindle handle to its
rear most position and depress the tommy bar and turn it approx. 90
°
so as to keep it down. The nut on the spindle shaft (which has a left-
hand thread) may now be slackened by means of the spanner, the
shaft being fixed by the tommy bar. Remove nut, washer and flange
(fig. 2.14). Mount the cut-off wheel, placing a cardboard disc on
either side of the wheel to prevent damage to the cut-off wheel.
Refit flange, washer and nut, tightening the nut slightly with the
spanner.
Finally, close the door and release the tommy bar by turning it
approx. 90
°
, this causes it to "come out" again. Always remember to
do this before starting the motor after exchange of cut-off wheel to
avoid blocking of the motor.
Abrasive cut-off wheels are made from abrasive grains set in a
bonding material processed into a thin disc.
The abrasive material is generally either aluminium oxide (Al
2
O
3
) or
silicon carbide (SiC). Being more brittle than Al
2
O
3
, SiC is mainly
used for relatively soft and short-chipped materials like copper,
copper alloys, cast iron, (stain less steel), tungsten, titanium,
zirconium (refractory metals), whereas Al
2
O
3
is used mainly for
carbon steel, cast iron, stainless steel, nickel (refractory metals).
Usually the bonding material is either bakelite or rubber, but since
rubber gives off an unpleasant smell, all of Struers cut-off wheels
have a bakelite bond. To provide a range of cut-off wheels of
different properties matching different materials we produce a variety
of bonds, differing with respect to hardness and porosity. The
hardness and the porosity are adapted in such a way that the bond
will disintegrate at the same rate as the abrasive grains are wearing
out. Thus the grains will fall out when they have lost their cutting
ability, and fresh and sharp grains are revealed. Wheels made of a
slowly disintegrating material are referred to as hard wheels,
whereas those made from rapidly disintegrating material are called
soft wheels.
Daily Routines
Mounting of Cut-off Wheel
Consumables and Accessories
Consumables