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DIAMOND SAW BLADES
SELECTINGANDMAINTAININGADIAMOND SAWBLADE
1. Identify type and hardness of material to be cut.
2. Determine correct blade speed. Blade speed must be
matched to the blade used and material to be cut. Hard materials
and thick blades require slower speeds. Soft material and thin
blades require faster speeds. Refer to Guide to Operating Speeds
for Blades below. Thicker blades are generally more durable and
last longer, but thinner blades reduce material loss.
3. Evaluate capacity of your saw, and motor RPM. Make sure
that your saw runs at the correct RPM's for the diameter of the
blade. The chart at the bottom of this page shows speeds for mo-
tors running at 1750 RPM. Speed is determined by multiplying
the motor RPM by the motor pulley diameter and then divided
by the equipment pulley diameter. For example a saw with a
1750 RPM motor, a 3.0" motor pulley, 2.5"arbor pulley will op-
erate at a blade speed of 2100 RPM's. (1750 x 3.0 ÷ 2.5 = 2100)
Referring to the "Guide to Operating Speeds for Blades" you
will see that this is a correct speed for blades from 5" to 10" in
diameter. If your saw is not operating at the desired speed, you
will need to change the pulley sizes.
4. Consider coolant requirements. Saws with steel parts
should be used with an oil type coolant, like our Roc-Oil. Steel
core blades work best with oil. If water is used as a coolant,
blade must not be left immersed in water.
5. Select rim style. Sintered continuous blades are a good all
around lapidary blade. Segmented or notch rim blades have an
interrupted surface which increases waste removal and coolant
flow.
6. When installing a new blade check your arbor shaft for ra-
dial and axial play. Try moving the shaft back and forth and in
and out. Any movement indicates that the shaft needs adjust-
ment, new bearings, or replacement. Lapidary blades are manu-
factured to fit snug on the shaft. If the shaft is worn the blade
will not spin concentrically and may bind or wear prematurely.
Make certain that all belts on your saw are in good condition and
properly tensioned.
7. Flanges are required to support the blade during operation.
Flanges must measure at least one quarter of the blade diameter,
so a 6" diameter blade would require flanges at least 1.5" in di-
ameter. Make certain that flanges are smooth, flat and parallel.
Flanges should be recessed about three quarters of their diam-
eter from their center. This supports the blade while avoiding
distortion of its center core.
8. Start cuts by feeding in the work piece when the blade is
running at operating speed. If the blade starts cutting to either
side of its plane of rotation, you will get a nonparallel cut and
may damage the blade. When cut is almost complete, a break
may occur, leaving a jagged spur. This spur can damage the
blade. To prevent this, infeed pressure should be reduced near
the end of the cut.
9. A diamond blade will be come dull or glazed along the cut-
ting edge during use. To sharpen the blade, make a few cuts into
a dressing stick, such as those on page 58. CAUTION: DO NOT
sharpen plated blades.
10. Diamond on Continuous Rim, Notch Rim and Segmented
diamond blades cannot be replaced. Saw Blade manufacturers
do not offer repair services of any kind. Be sure you read all
recommendations prior to using your diamond saw blade.
1.5 2.0 2.5 3.0 3.5 4.0 4.5 5.0 6.0 7.0 8.0 10.0
1.5 1750 1313 1050 875 750 656 583 525 438 375 328 263
2.0 2333 1750 1400 1167 1000 875 778 700 583 500 438 350
2.5 2917 2188 1750 1458 1250 1094 972 875 729 625 547 438
3.0 3500 2625 2100 1750 1500 1313 1167 1050 875 750 656 525
3.5 4083 3063 2450 2042 1750 1531 1361 1225 1021 875 766 613
4.0 4667 3500 2800 2333 2000 1750 1556 1400 1167 1000 875 700
4.5 5250 3938 3150 2625 2250 1969 1750 1575 1313 1125 984 788
5.0 5833 4375 3500 2917 2500 2188 1944 1750 1458 1250 1094 875
6.0 7000 5250 4200 3500 3000 2625 2333 2100 1750 1500 1313 1050
You can calculate the equipment shaft speed for other motor speeds by multiplying the motor rpm by the motor pulley
diameter and then dividing by the equipment pulley diameter.
Equipment Arbor Pulley Diameter
Motor
Pulley
Diameter
Table yields arbor shaft rpm (revolutions per minute) for a 1750 rpm motor
GUIDE TO OPERATING
SPEEDS FOR BLADES
The chart below shows the recommended operating range for
4" to 36" saw blades. To select the best speed see instructions
2 and 3 of Selecting and Maintaining a Diamond Saw Blade.
Blade Diameter
(inches)
Revolutions
Per Minute
Blade Diameter
(inches)
Revolutions
Per Minute
4
2400-5700
14
750-1600
5
1900-4500
16
700-1400
6
1600-3800
18
600-1200
7
1400-3200
20
550-1100
8
1200-2800
24
450-950
9
1100-2500
30
350-750
10
950-2200
36
300-700
12
800-1900