Power Saws Flashcards
What are the four commonly used saws used by millwrights?
Power hacksaw-not common
Horizontal bandsaw (cut-off saw)
Vertical bandsaw (contour)
Abrasive cut-off saw
What is SPM?
What machines measures speed that way?
Strokes per minute
Power hacksaw.
Number of saw blade teeth per inch?
Blade pitch
Thickness of the body of a blade behind the teeth?
Blade gauge
Distance from the tip of the tooth to the back of the blade?
Blade width
The width of the cut the blade makes?
Blade kerf
The way the individual teeth are bent out of line with the blade body?
Blade set
What is a horizontal bandsaw used for?
How is the size measured?
Most commonly used as a cutoff saw.
Measure by the largest size of material it can cut.
What is SFPM/SMPM?
Surface feet per minute/surface meter per minute
Why should coolant and cutting fluids be used?
-Provides lubrication and cooling
-Prolong life of saw blade
- water is best but causes rust, oil does not cause rust but not as efficient.
- soluble oils and chemicals need to be added to the water to prevent rust
What properties should chemical agents for cutting have?
Provide rust control
Have resistance to rancidity
Reduce heat generated from cutting
Separate waste chips from workpiece
What is a vertical bandsaw (contour) used for?
Cutting shapes Notching Slotting Internal contour sawing Angular cutting Splitting Three dimensional shaping
How is capacity measured with a vertical band saw?
Throat distance
What are the 3 common blade materials and there properties?
High carbon steel-either hard backed blade for straight accurate cuts in low carbon steel and non-ferrous metals. flexible backed blades for ferrous metals and contoured surfaces
Bimetal-greater wear and heat resistance.
Tungsten carbide-same as bimetal blades but have a carbide tip. Faster, smoother cutting
What are the three types of teeth for band saw blades?
Standard-general purpose
Hook tooth-soft metals, plastics, wood
Skip tooth-soft materials or workpieces with thick cross sections
What are the three blade sets?
Raker-general purpose
Wavy- distinct change in cross section ie, pipe
Straight/alternate-rough fast cutting
What are the two types of pitch on a bandsaw blade?
Variable-varies in tooth size,depth and gullet.
Constant-uniform spacing of teeth, gullet depth and rake angle. (General purpose)
Soft materials require what pitch of blade?
Harder materials require what pitch of blade?
Soft materials require courser pitch(fewer teeth)
Harder materials require finer blade.
Annealing is?
Takes the hardness and brittleness out of the blade after welding
What is friction sawing?
Friction sawing cuts steel by generating enough heat to soften the steel ahead of the blade.
Can not use the method aluminum or copper because they dissipate heat to quickly.
What is a cutoff saw used for?
To cut hardened metals, glass, ceramic, brick and stone.
Best suited for cross sections under 2 inches
What are the 3 types of abrasive grit for cutoff saws?
Aluminum oxide-cutting steel and most other materials
Silicone carbide-non ferrous metals
Diamond-ceramic, stone and brick
Tensioning a horizontal bandsaw blade is done by?
Tensioning the bandsaw blade just tight enough to hold it on the pulley’s.
Start and stop the machine quickly slowing the blade to make a couple turns around the pulleys. This will position the blade on the pulley.
Tension blade
If bandsaw blade jumps and shutters it means?
The feed is to high
When should I wear gloves while operating a bandsaw?
Only when changing the blade and handling roughy dirty material.
Not while machine is in operation.
How do you track the blade on a vertical band saw?
The head houses the upper pulley, which can be tilted from side to side by a hand wheel mounted in the centre of the pulley.
By adjusting the pulley tilt you can track the blade to ride in the centre
Why does starting a new blade in a old unfinished cut tend to jam on a bandsaw?
Because the old blade probably cut a slightly smaller kerf (width of cut)
What is the grinding wheel for and a vertical bandsaw?
To square the ends of the blade and to grind off the weld after welding blade together
If blade ends are not square what will happen after welding?
Blade will have a slight bow in the area of the weld
Where should the weld be on a vertical band saw blade?
At the bottom of the gullet
When grinding the welded blade make sure to not grind teeth and check the thickness after with the______?
Blade gauge
Grinding and rapid cooling may cause the blade to become brittle and need to be annealed again. Check blade by bending back and forth near the weld area
