shadow

Care, Maintenance & Operation of Rotary Saws

Our gasoline-powered rotary (K-12 and K950FD) saws are powerful and effective rescue, forcible entry and ventilation tools. The saw’s safety, performance and reliability depend on how well the saw is inspected at shift change and after each use, the skill of the operator and the operator’s knowledge of cutting techniques. Our saws have the potential to seriously injure an operator and firefighters working near its operation. There are three main causes of injuries from rotary saws; they are:

  1. Accidental contact with a rotating blade
  2. Being struck with projectiles of blade fragments or the material being cut
  3. Burns, from the ignition of fuel that leaks from the saw, or flammable liquids in the
    area where the saw is operated.

The following procedures will be adhered to when operating a power saw:

Thoroughly inspect saws at shift change and after each use. Begin the inspection by inverting the saw so that its fuel cap is upside down. This will ensure that the cap and its rubber “O” ring gasket are not leaking. Fuel dripping from an inverted saw could be the result of its overfilling; fuel that overflows the fuel tank can collect in cavities in the engine housing. Also, consider that ethanol, up to 10% in gasoline, can, over time, dry out and crack seals and fuel lines on 2 cycle engines causing them to leak. Next, examine the blade on the saw and spare blades onthe apparatus for cracks, missing teeth or missing segments of diamond blade. Check to make sure that the blade is tight and that there are no screws or bolts that have vibrated loose. Now start the saw and let it idle for about 10 seconds before bringing it up to full RPM. It is very important to note any unusual vibration; which could be the result of a loose, cracked or warped blade. After running the saw, allow the engine to cool a few minutes and add fuel to the fuel tank. To prevent over filling the tank and spilling fuel, use a funnel and add fuel to the saw while it is in its upright position. Never fuel the saw while it is on its side; it will allow you to add a few more ounces of fuel but it is not worth the risk of overfilling the tank and spilling gasoline. Inspect the fuel cap’s rubber “O” ring gasket for deformity – a result of over tightening the fuel cap. Deformed or flattened “O” ring gaskets should be replaced with a new one available from our Mobile Equipment’s small engine mechanic. Fuel filler caps on power saws are designed to be “finger tight”. Do not use a tool to tighten the cap. A close examination of a leaky fuel cap will usually reveal marks on the plastic from pliers used to loosen an over tightened cap. After fueling, invert the saw again to ensure that the fuel cap is not leaking.

Never lift or carry a saw with its blade rotating. Contact with a spinning blade can result in a devastating injury. To stop a rotating blade, release the throttle and gently press the blade on the pavement or the material you were cutting. A saw should run at idle speed without its blade rotating. A saw that must have its throttle repeatedly “gunned” to keep it running is dangerous to use and should be tagged for repair.

Saw operators and all personnel working near an operating saw should wear full protective clothing’ especially eye protection. A blade spinning at 5500 RPM has sufficient centrifugal force to throw sparks, fragments of the material being cut and pieces of broken blade a considerable distance. Catastrophic failure and fragmentation of diamond metal-cutting blades is almost always the result of overheating when a saw operator attempts to cut faster than the saw was designed to cut.

This diamond metal-cutting blade failed due to overheating

This diamond metal-cutting blade failed due to overheating


Blade fragments penetrated the blade guard.

Blade fragments penetrated the blade guard.


When cutting heavy gauge steel or iron bars allow the blade to cool by occasionally withdrawing the blade from the cut and let it spin freely. Listen to the saw and let the saw determine its cutting speed. It is designed to cut at or near its maximum RPM. Attempting to cut faster than the saw will allow can bind and overheat the blade and damage the saw’s centrifugal clutch. A decrease in RPM is a signal to back off on the saw and allow the blade to regain its speed. Additionally, a rotary saw operator and anyone working near a rotary saw that is being used to cut laminated impact resistant “hurricane” glass will inhale airborne glass dust and fragments. It is, therefore, highly recommended to use SCBA. Protective clothing can prevent saw operators and firefighters working near an operating saw from being burned. Keep in mind that even the best maintained saw could begin leaking fuel while it is in operation. Additionally, sparks produced by a saw could ignite dry grass, foam insulation or an accelerant poured by an arsonist.

A fatigued saw operator is a dangerous saw operator. Firefighters will rarely admit that they are tired and need to be relieved. It is, therefore the Company Officer’s responsibility to rotate members before they become a hazard to themselves and other firefighters. Usually the first sign of operator fatigue is the saw’s blade binding as they lose the strength to hold the saw steadily.

Heavy steel doors, strong lock assemblies and thick iron security bars have made the K-12 rotary saws a necessity for our Department. It’s safe and effective use depends on how well it is inspected, maintained and operated.

Thanks to Captain William Gustin (Battalion 5C) for his assistance in writing this Safety Zone.

Let’s Be Careful Out There!

Calendar

Sep 29-30, 2011 Intelligent Firefighting “Be Aggressive . ..Don’t Be Stupid”

With Capt Bill Gustin, Miami Dade Fire Rescue Double Tree Milwaukee City Center Milwaukee, Wisconsin

Sep 29-30, 2011 Intelligent Firefighting “Be Aggressive . ..Don’t Be Stupid”

With Capt Bill Gustin, Miami Dade Fire Rescue Double Tree Milwaukee City Center Milwaukee, Wisconsin

CLICK TO SCHEDULE