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HomeMy WebLinkAbout309.002b - Husqvarna K770 Cutting SawEffective Date: March 2024 Robert Camp, Battalion Chief Current Revision Date: 03/28/2024 Section 309.002b Next Revision (2) Date: 03/28/2026 Page 1 of 10 300 Training and Equipment Manual SECTION 309.002b HUSQVARNA K770 CUTTING SAW PURPOSE The purpose of this procedure is to provide instruction to Fresno Fire Department (FFD or Department) members on the proper use and maintenance of the Husqvarna K770 cutoff saw. APPLICATION When equipped with the proper blade, the saw can be used to cut a variety of substrates to include most metals, masonry, wood-based materials, construction materials, rubber, plastic, and glass. OPERATIONAL POLICY This section intentionally left blank. OPERATIONAL GUIDELINE Safety Precautions: • Always wear the appropriate personal protective equipment when using the saw. This includes full turnouts, helmet, gloves, and eye protection. • Never set the saw down, shift hands, or hand it to another person until the saw is at idle speed. • Ensure all personnel not in control of the saw place themselves a significant distance away while in use. The cutoff saw is capable of dislodging and throwing objects such as nails, small rocks, and blade teeth a considerable distance, especially to the rear of the saw. • The shoulder strap should only be used on the saw when the blade has been installed in the inboard position. Fresno City Fire Department Effective Date: March 2024 Robert Camp, Battalion Chief Current Revision Date: 03/28/2024 Section 309.002b Next Revision (2) Date: 03/28/2026 Page 2 of 10 PROCESS 1. Starting the saw with a cold engine: a. Make sure the STOP switch is in the left position. (See figure 1, #10.) b. Pull the choke control fully to get into the start throttle position. (See figure 1, #7.) c. To decrease the pressure in the cylinder the decompression valve may be engaged. (See figure 1, #19.) d. Push the air purge bulb six times. (See figure 1, #20.) e. Cutoff saws may be “drop” started or placed on the ground. Secure the front handle in the left hand and pull the starter rope slowly until the starter pawls engage, then pull continuously and quickly. f. Once the engine is started, push the choke control into the saw to disengage the choke. g. Push the throttle trigger to disengage the start throttle which allows the saw to be set at an idling speed. (See figure 1, #8.) 2. Starting the saw with a warm engine: a. Make sure the STOP switch is in the left position. (See figure 1, #10.) b. Pull the choke control fully to get into the start throttle position. (See figure 1, #7.) c. To decrease the pressure in the cylinder the decompression valve may be engaged. (See figure 1, #19.) d. Push the choke control into the saw to disable the choke. The start throttle stays in the start position. (See figure1, #20.) e. Cutting saws may be “drop” started or placed on the ground. Secure the front handle in the left hand and pull the starter rope slowly until the starter pawls engage, then pull continuously and quickly. f. Push the throttle trigger to disengage the start throttle which allows the saw to be set at an idling speed. (See figure 1, #8.) Effective Date: March 2024 Robert Camp, Battalion Chief Current Revision Date: 03/28/2024 Section 309.002b Next Revision (2) Date: 03/28/2026 Page 3 of 10 3. Stopping the saw: a. Let the saw idle down for at least 15 seconds. b. Move the STOP switch to the right. (See figure 1, #10.) c. The blade will briefly continue to spin after the stop switch is engaged. d. After use, visually inspect the saw to verify no damage has occurred. The saw should be properly cleaned, allowed to cool, and then refueled. The saw should be reset to the starting position. The saw should not be stored with the decompression valve depressed, which may allow moisture to enter the cylinder. Figure 1 Effective Date: March 2024 Robert Camp, Battalion Chief Current Revision Date: 03/28/2024 Section 309.002b Next Revision (2) Date: 03/28/2026 Page 4 of 10 4. Cutting: • Be aware of reactive forces, especially when cutting with the front portion of the blade. • Throttle up to full rpm, begin cutting and continue at full speed. • If possible, avoid standing in direct line with the blade. • Be aware of pinching or twisting the blade. • Maximum cutting efficiency is obtained by pulling rather than pushing the saw through the material to be cut. Note: For prolonged cuts, use fine water spray to keep the blade cool. 5. Blades: • The Husqvarna cut off saw can be equipped with either the Klingspor All Cut Rescue blade or the Fire Hooks Unlimited carbide toothed blade. It will be at the discretion of the individual Truck company members as to which blade should be installed on the saw. • The Klingspor DT900, 12-inch, All Cut Rescue blade is a diamond cutting blade which can be used to cut most metals masonry, wood-based products, rubber, plastic, and glass. This blade is a directional blade and should be installed accordingly with the rotation of the saw. • The Fire Hooks Unlimited CBT 12x12 is a 12-tooth, 12-inch carbide toothed blade which can be used to cut wood-based construction materials, roofing materials, and light gauge sheet metal. This blade is a directional blade and should be installed accordingly with the rotation of the saw. • Both blades can be requested from the Fire Shop Parts Section via PSTrax. • After each use the blades should be cleaned and inspected. o The blades can be washed using mild soap or detergent and water. Effective Date: March 2024 Robert Camp, Battalion Chief Current Revision Date: 03/28/2024 Section 309.002b Next Revision (2) Date: 03/28/2026 Page 5 of 10 o Monitor for stress cracks. o Inspect blade for warping that may have occurred during usage. 6. Arbor Size: • The arbor bushing on the saw can be installed in reverse to accommodate both 20mm and 1 inch arbor blades. 7. Fueling: • This saw requires 50:1, 2-stroke fuel mixture. 8. Blade Removal/Installation: a. Blade Removal: i. Insert the multi-tool into the hole on the front belt guard and turn the cutting blade until the shaft is locked. (See Figure 2.) Figure 2 Effective Date: March 2024 Robert Camp, Battalion Chief Current Revision Date: 03/28/2024 Section 309.002b Next Revision (2) Date: 03/28/2026 Page 6 of 10 ii. Loosen the cutting blade bolt. (See Figure 3.) Figure 3 A. Arbor bushing B. Inner Flange Washer C. Outer Flange Washer iii. Remove blade. b. Blade Installation: • Place the cutting blade on the arbor bushing between the inner flange and outer flange washers. Turn the flange washers until engages with the shaft. Insert bolt into spindle and tighten. 9. Repositioning Blade Orientation from Outboard to Inboard: (See Figure 4.) Figure 4 Effective Date: March 2024 Robert Camp, Battalion Chief Current Revision Date: 03/28/2024 Section 309.002b Next Revision (2) Date: 03/28/2026 Page 7 of 10 a. Remove blade, loosen the cutting head nuts, and remove shroud stop nut. (See Figure 5.) Figure 5 b. Rotate cutting head downwards. (See Figure 6.) Figure 6 Effective Date: March 2024 Robert Camp, Battalion Chief Current Revision Date: 03/28/2024 Section 309.002b Next Revision (2) Date: 03/28/2026 Page 8 of 10 c. Release drive belt tensioner. (See Figure 7.) Figure 7 d. Remove the drive belt and rotate cutting head into the inboard position. (See Figure 8.) Figure 8 Effective Date: March 2024 Robert Camp, Battalion Chief Current Revision Date: 03/28/2024 Section 309.002b Next Revision (2) Date: 03/28/2026 Page 9 of 10 e. Apply the drive belt tensioner and install the cutting head nut assembly. f. Replace the shroud stop bolt. g. Install the blade. 10. Care and Maintenance: a. After Use Check: 1) Clean dust and debris from saw. 2) Check the blade. 3) Check the blade belt tension. 4) Check the blade guard for security and proper position. 5) Refuel as necessary. b. Weekly Check: 1) Check the fuel level. 2) Check the blade for security and proper rotation. 3) Check the belt tension. 4) Check for cleanliness. 5) Start the engine and check for smooth operation at all speeds. Note: The proper warm up procedure to warm up small engine equipment should be to start the engine, let the engine idle for 15 seconds, apply ¼ throttle for 6 seconds, let engine idle for 15 seconds, apply ½ throttle for 6 seconds, let engine idle for 15 seconds, apply 3/4 throttle for 6 seconds. The small engine equipment is now ready for use. Effective Date: March 2024 Robert Camp, Battalion Chief Current Revision Date: 03/28/2024 Section 309.002b Next Revision (2) Date: 03/28/2026 Page 10 of 10 INFORMATION Specifications Engine: 2-Stroke, 5 hp, 4.48 Cu. Inch Spindle Speed: 4700 rpm Weight: 22 lbs Fuel Capacity: 30 fl.oz. Depth of Cut: 4 inches, with a 12-inch blade Arbor Size: 20 mm/ 1 inch DEFINITIONS This section intentionally left blank. CROSS-REFERENCES No cross-references identified.