Craftsman 351.214300 - Manual (Page 8)

BLADE SPEED AND BLADE PITCH CHART (FEET PER MINUTE/TEETH PER INCH)
MATERIAL
THICKNESS:
1/4" 1/4-1" 1-3" 3-6" 6-10"
High carbon steel 230/18 200/14 200/10 150/6 150/4
Free cutting steel 200/18 150/14 130/12 100/6 100/4
Ferro-manganese 200/18 156/14 130/12 100/8 100/4
Ferro-nickel 165/18 130/14 100/12 75/8 75/4
Ferro-nickel-chrome 130/24 100/18 75/14 66/8 66/6
Ferro-molybdenum 150/18 130/14 100/12 75/8 75/6
Ferro-chrome (med.) 165/18 100/14 75/12 66/8 66/6
Ferro-chrome (high) 100/24 75/14 66/10 66/8 66/6
Manganese steel 180/18 150/14 115/12 100/8 66/4
Ferro-tungsten 150/18 100/14 75/12 66/8 66/4
Ferro-chrome-vanadium 165/18 100/14 75/12 66/8 66/4
Ferro-silicon-manganese 150/18 130/14 100/10 75/6 75/4
Machinery steel 180/18 130/14 115/12 100/6 66/4
Ordinary tool steel 130/24 100/18 100/14 80/8 75/4
High speed steel 100/24 75/14 66/12 66/8 66/4
Stainless steel 130/18 100/14 75/10 66/8 66/4
Thick iron plate 165/18 130/12 75/10 66/8 66/4
Cast iron 200/18 200/14 1 50/12 75/8 75/4
Nickel cast iron 200/18 150/12 100/8 66/6 66/4
Forgeable cast iron 200/18 165/14 150/10 130/6 130/4
High grade cast iron 150/18 130/14 100/10 75/6 66/4
Coarse cast iron 200/18 165/14 130/10 75/6 75/4
Tombac 1480/18 1000/12 750/8 95/6 295/4
Bronze 245/18 245/12 225/10 200/6 150/4
Phosphorus-bronze 490/18 295/14 200/10 150/6 150/4
Nickel aluminum bronze 490/18 295/12 225/10 150/6 150/4
Magnesium-bronze 295/18 245/12 225/10 150/6 150/4
Hard aluminum 2000/18 2000/10 2000/8 2000/6 1480/4
Aluminum 2000/18 1650/10 1300/6 820/4 490/3
Copper 395/18 295/12 245/8 150/6 150/3
Fibers 1480/24 1300/18 1000/6 750/4 750/3
Asbestos 1300/24 1000/18 660/14 490/10 330/6
TYPE OF TOOTH
• The shape of teeth are varied to achieve specific
cutting results. A blade cuts work by removing
material. Blade teeth must scrape a chip of
workpiece away on each cut.
• The shape of gullet between teeth determines how
much material can be taken out with each blade
tooth.
• There should always be at least three teeth in con­
tact with workpiece to avoid shocking blade. Blade
shocking occurs when pitch is too large and blade
tooth encounters too much material. This can strip
teeth from blade.
• When pitch is too small, gullets of teeth will fill up
leading to creation of excess heat.
• Rake angle is the angle which the cutting face of
tooth makes with a line perpendicular to the back of
blade. A 0° rake angle is used to cut hard materials.
• Positive rake angle blades are used to cut softer
materials. Softer materials require more aggressive
chip removal.
• Larger gullets provide for faster removal but have to be
limited in size because they make blade teeth weaker.
• Blade teeth will also vary in the way that teeth have
been set from one side to the other. A wider set is
used for contour work because wider kerf allows
operator to cut tighter curves.
CHANGING BLADE SPEED
Refer to Figure 15.
WARNING: Never adjust blade speed unless machine
is running or damage to saw may result.
• Blade speed is adjusted by rotating handwheel (Key
No. 50) while machine is running. Rotate handwheel
clockwise to increase blade speed. Rotate hand­
wheel counterclockwise to decrease blade speed.
The blade speed is shown on LED display located
above switches.
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