TB 44: Rotary Saw Flashcards
The rotary saw is a versatile high speed, hand held, gas powered cutting device designed to cut solid materials such
steel, wood, masonry or polycarbonate
utilized in a variety of operations such as
forcible entry, ventilation and USAR operation
Each rotary saw will have access to several different
blade types, a scrench tool, and a blade board
allows for members to have a variety of options while on scene of an emergency
The LAFD carries 4 types of 14” rotary saw blades. What are they?
Abrasive Blade
Combi-Blade
Diamond Blade
Carbide Tooth Blade
Each blade type has a specific use. Each rotary saw should be accompanied by a blade board that has an assortment of blades that best fits the needs of the district. All companies shall have at least
one of each blade type available
METAL CUTTING ABRASIVE BLADES
- consists of grit bonded by an organic binder
- Reinforced blades” are made up of a fabric or fiber base, preventing total breakage at maximum working speed
- used on steel, steel alloys and other hard metals
-not be used on soft metals such as aluminum or brass
Blades shall be a minimum of
12” to remain in front line service.
Blades used during emergency operations may become
smaller while performing extensive cutting operations
-used until it is no longer effective or safe
Blades smaller than 12” may be used for
training purposes
Blades below 9” shall be sent into
shops for replacement
Abrasive blades shall be removed from service if there are signs of
petroleum product contamination or cracks
-could render the blade unsafe
Blades that are no longer safe for use shall be marked with
F-175 Tag
word “UNSAFE” shall be marked on the blade
COMBINATION “COMBI” BLADE
- diamond blade that consists of a steel flat metal disc with synthetic diamonds bonded to the outer edge
- do not have teeth to cut; rather they have exposed diamond crystals used to grind the material
Stamping or printing by the manufacture near the arbor with “Metal/Steel”, “Metal Cutting”, or “Concrete/Metal” indicates
combination use blade
Combi-blades can be used to cut
bare metal, concrete, reinforced concrete, masonry or Robertson Decking
-All Combi-blades are bi-directional
Combi-blade is not designed to cut
soft metals such as brass or aluminum
-however it can cut thin, soft metal found on train siding, aircraft siding, metal clad doors, or aluminum gates
Any glazing or buildup of material on the diamond segment can be cleaned by
cutting into a soft material such as brick, cinder block or asphalt
After several thousand grinding rotations, the exposed matrix holding the diamonds begins to
wear and fracture
Matrix erosion exposes new sharp diamonds. This cycle of erosion and exposing continues until
all of the diamond and bond section of the segment is gone
Combi-blade had a continuous cutting depth of
4¾”
Combi-blades shall be forwarded to Supply and Maintenance for replacement when:
- Any one segment is fractured, broken or missing.
- Bald spots along any of the segments occur.
- Matrix bond is equal to the thickness of the blade body; a step or lip no longer exists
CONCRETE DIAMOND BLADES
similar in construction to the Combi-blade
- designed as a directional cutting rotation
- arrow stamped or printed on the blade indicating the proper rotation
Concrete diamond blades are designed to
Cut concrete and metal encased in concrete
*Do not attempt to cut bare metal with this blade!
Glazing or build-up of material on the diamond segments, can be cleaned by
Cutting in a soft material such as brick, cinder block or asphalt
As with the Combi-blades, Diamond blades shall be forwarded to Supply and Maintenance for replacement when
- Any one segment is fractured, broken or missing.
- Bald spots along any of the segments occur.
- Matrix bond is equal to the thickness of the blade body. No step or lip exists.
CARBIDE TIP BLADE
tempered metal blade, carbide tipped
- cutting composition roofing material, wood, and Lexan
- Use on light sheet metals such as door cladding or aluminum sheet with care
- After use, check damage and sharpness. If a missing tip or a visible radius appears, fill out a F-175 tag and send the blade to Supply and Maintenance for replacement
safety equipment should be used while operating the saw
Gloves
Eye Protection
Helmet
Brush Jacket/Turn out coat
Engage the half throttle. This is accomplished by engaging the throttle and
depressing the throttle lock button on the left side of the throttle assembly
Pulling out the choke on the K-970 will
Activate the half throttle position
The half throttle will remain engaged until the throttle trigger is
Engaged even if the choke is pushed back in
What will assist in starting the saw?
Pressing in the compression valve
Automatically returns to its initial position when the saw starts