Group 30 - Ryobi Contractor's Saw
Skil 2.3 HP Circular Saw
Our group was assigned to analyze the physical and operational characteristics oh a 2.3 hp Skill circular saw. This report will include a description of the overall design concept and manufacturing processes that were used to construct this saw. Additionally, we will examine the materials used and the overall technical concepts that were implemented to make the operation of this component possible and make assumptions based on knowledge we gained this semester to explain why many of these concepts were used.
We began simply by brainstorming assumptions of the basic concepts of how the saw worked and what components and materials we could expect to come across upon disassembly. During the disassembly we identified each component and considered its purpose. This process took approximately 45 minutes.
The saw can be broken down into two different sub-assemblies that are coupled together via a reduction gear and a few 1 7/8 in. 30 Torx screws. The first sub-assembly is the 12 Amp electric motor and its casing. The motor drives a shaft that is coupled to the saw assembly which is comprised primarily of mechanical components.
-30 Torx driver
-20 Torx driver
-Ball peen hammer
-3/4 Combination wrench
-Needle nose pliers
1) Using a 30 Torx driver we removed the 1-7/8 in. screws that attached the saw handle to the motor assembly as it interfered with the rest of the dissection.
2) Once the handle was removed we detached the motor housing from the saw assembly by removing the remaining 30 Torx 1-7/8 in. screws.
3) At that point we attempted to remove the motor housing, but found that the guide plate interfered.
4) Using a ball peen hammer and a die we tapped the pin that secured the guide plate in its place free.
5) From that point we were able to remove the motor housing and expose the rotor assembly.
6) Additionally, you could see the back side of the shrouded plate, the cog gear and the main support bearings for the saw blade and rotor.
7) The stator could be seen inside the motor housing.
8) Using a 20 Torx driver we removed the vented cap from the end of the motor housing.
9) That step exposed the two 2-1/2 in. 20 Torx screws that held the stator in place as well as the carbon brushes that rode on the commutator.
10) Once the Torx screws that held the stator in place were free we carefully removed the stator and brushes from the motor assembly by using the plyers.