A few years back it was decided that circular saws ordered for the rescue and truck companies would be the same model and manufacturer. The reasoning was sound; the new saw was lighter weight, through testing they believed it was of good power and the single manufacture would make parts, service and arbors all standard. In time we found that one saw does not fit all.
I understand that we do not all have the luxury of having two circular on our rigs let alone have a say in the setup. I hope that our experience in this matter may prevent a similar decision or improve your operations.
Forcible Entry Saw – 73cc circular saw – 14” composite blade mounted outboard – 26 lbs
The forcible entry saw is in first out position in the compartment. This saw needs to be immediately available for us to gain entry, remove window bars and support interior operations which typically are moving forward upon our arrival. The forcible entry saw must have good power however, the rotational mass of a composite blade and the mass of material being cut is typically less than that of a roof saw therefore a smaller displacement saw can get the job done. The added benefit of choosing a smaller displacement saw for forcible entry operations is the weight of the saw. When cutting locks, bars, hinges and doors the saw is nearly 100% of the time being operated in free space. Our forcible entry saw is 10lbs lighter than our roof saw. This nearly 30% reduction in weight goes a long way for the operator who may have to make multiple cuts along the side or rear of a commercial occupancy. Outboard mounting of the blade allows for improved access in tight spots (up against a wall) or working overhead on window bars. A quick tip on maintaining the forcible entry saw is to exercise and lube the blade guard frequently so it is easily adjusted in operations for best positioning.
Flat Roof Saw –119cc circular saw – 12” 12 tooth Warthog Blade mounted inboard – 36lbs
The flat roof saw is second out of the compartment. Our flat roof saw is the larger saw; the duties it serves are more demanding especially the initial plunge cut requiring greater power. The blade is much more aggressive to clear more material and with a wider kerf of ¼” to assist with the louver. The greater weight of this saw and higher rotational mass of the blade is not an operational issue as long as it remains on the deck during cuts
Having knowledge of your cut depth is helpful when you go to the roof. Most of our flat roofs are built up material in the ball park of 2” to 4” with decking, insulation and waterproofing. There are places where this roofing may exceed this range to create drainage or just due to “re-roofs” and a step cut may be required.
The flat roof saw blade is mounted inboard for good reason. “As your hand goes so does the blade.” It is important to allow the saw to work, keeping your body position behind the saw, dragging it in a straight line so that the blade is only cutting in one plane as the teeth come out of the roof and pass through the decking. Working to the side of the saw will inherently kick the saw out. Even just a few degrees of camber will force the saw blade to cut on its way in and on its way out bogging it down and potentially giving you a false recognition of a structural member. The added benefit of staying behind the saw will allow for a pivot on the wrap around handle bringing the blade up out of material when you roll rafters.
This is a brief post on a bigger topic which may be dangerous. Blade selection, saw set up and ventilation methods are heavily influenced by resources, experience and local construction. I choose to bring this forward as a presentation on knowledge of tools and attention to detail in preparation for mission over a statement of how you should be running your companies. I also hope that a post of this nature in this community will bring forth discussion and presentation of other methods and setups so that through networking we can all gain from each other.