Entire Product Complexity G152011

Component Complexity

Whenever you are evaluating parts of a machine it is very important to know how complex the underling manufacturing processes are. However, this could be very difficult for the average user to ascertain. That is why we created a manufacturing complexity scale for every component in our 26 cc Craftsman weed wacker. The component complexity scale is a rating of the difficulty it takes to manufacture a given part. For the sake of simplicity we arbitrarily selected a scale of 1 to 4, as explained below.

In our scale a 1 was awarded to any part that was easily produced through a single manufacturing process. This kind of piece would include components that were made by forging, die cutting, die casting, or injection molding. A 2 was awarded to any piece that required two simple manufacturing processes, such as forging twice or forging and injection molding. On our scale any component that required a difficult process warranted a rating of 3; this included things like milling. Finally, any component that had to be made through one difficult process in conjuncture with other processes was classified as a 4. An example of this would be any piece that had to be die cast and milled.

Both the component functions and geometry also played huge roles in the rating each component received. A complex manufacturing process is needed to make complex geometry, so our scale inherently rates the parts with more intricate geometry as harder to manufacture than those without it. Similarly the more important functions are typically done by pieces that were either very complex or needed tighter tolerance, and those are the pieces that received scores of 3 or 4 on our scale.

Interaction Complexity Scale

Our interaction complexity scale utilizes a 1-3 rubric, with 1 being parts that interact with few other components and 3 being parts that work in concert with many other parts to create the desired outcome.

• A 1 on our scale represents a component that has no significant interaction with any other parts. An example would be the plastic injection molding casing that covers the engine. This casing has no significant function in the generation of power, but it protects the engine and serves an aesthetic role.
• A 2 on our scale is a component that has minor involvement with other parts of the weed wacker. It may be something that is only connected to a few other parts, but it still does is relatively important to the overall function of the weed wacker. An example of this would be a bearing. A bearing is a simple part that does not interact with many other parts – it is typically used to hold another component in place. Its primary functions are to reduce friction and maintain the alignment of other critical pieces. This means that while it is only connected to one other component, it is intrinsically necessary for the production of power.
• A 3 on our scale is a component that is used in combination with many other parts, or one that is vital in a primary goal of the tool (such as creating power). An example of this type of part would be our piston. The piston is a central part of an engine – it creates the required compression and the subsequent power for the machine. The piston is connected to the crankshaft which helps move the piston through the cylinder. This is a simplified explanation for how important a piston is and how a piston is involved with many other parts of the engine; the goal here is merely to explain our scale.

Component Manufacturing Complexity Scale:

• 1-Simple one process manufacturing
• 2-Two simple process manufacturing
• 3-One difficult process
• 4-Combination of one difficult process and one simple

Interaction Complexity:

• 1-No interaction between parts besides being connected
• 2-Minor component involved with few moving parts to produce an outcome
• 3-Major component involved with many moving parts to produce an outcome

Part Ratings
Part: Large Housing Gasket

• Complexity: Not very complex. Basic design and function.
• Complexity Scale: 1
• Complexity of Interactions: Simple function of creating a seal.
• Interactions Scale 1

Part: Small Housing Gasket

• Complexity: Not very complex. Basic design and function.
• Complexity Scale: 1
• Complexity of Interactions: Simple function of creating a seal.
• Interactions Scale 1

Part: Carburetor Gasket

• Complexity: Not a very complex piece. It has a basic design and function.
• Complexity Scale: 1
• Complexity of Interactions: Simple function of creating a seal
• Interactions Scale 1

Part: Crankshaft Housing

• Complexity: Complex design to dissipate heat and protect crankshaft however it is made using only one manufacturing process.
• Complexity Scale: 1
• Complexity of Interactions: Protect the inner workings of the engine and help reduce heat.
• Interactions Scale 1

Part: Cylinder block

• Complexity: The outside of the cylinder is a very complex figure and the inside has to be milled so that it can reach the correct tolerances.
• Complexity Scale: 4
• Complexity of Interactions: Takes in the gasoline and then an explosion happens inside the cylinder and the piston shoots out as a form of mechanical energy.
• Interactions Scale 3

Part: Piston

• Complexity: Intricate design pattern on inside of piston and then milled to exact specifications.
• Complexity Scale: 4
• Complexity of Interactions: Interacts within engine to produce energy flow
• Interactions Scale 3

Part: Flywheel

• Complexity: The part has a lot of fine detail and needs to be perfectly balanced for safe rotational turns at a high speed, and there are multiple processes required to completly manufacture the component.
• Complexity Scale: 4
• Complexity of Interactions: Interacts with the engine to keep producing energy flow
• Interactions Scale 3

Part: Magneto and magneto wire

• Complexity: Simple design and shape yet difficult to make the combination of shapes necessary for this part
• Complexity Scale: 2
• Complexity of Interactions: Interacts with the flywheel and the sparkplug to keep producing a flow of electric energy
• Interactions Scale 3

Part: Carburetor

• Complexity: Many parts are intricately sized and milled and put together to form the component.
• Complexity Scale: 4
• Complexity of Interactions: Many parts work together to control flow of fuel and air mixture into the engine.
• Interactions Scale 3

Part: Crankshaft

• Complexity: Simple design yet required multiple manufacturing processes to finish
• Complexity Scale: 4
• Complexity of Interactions: A main component of the engine used to create power.
• Interactions Scale 3

Part: Bearing

• Complexity: Simple designs intricately put together to create component
• Complexity Scale: 2
• Complexity of Interactions: Helps provide fluid rotational energy with limited resistance.
• Interactions Scale 2

Part: Clutch

• Complexity: Each of the components has a simple shape however when these things are combined they become more difficult to create
• Complexity Scale: 4
• Complexity of Interactions: The design is simple yet it works perfectly to help translate rotational energy
• Interactions Scale 2

Part: Pull Start Mechanism

• Complexity: Simple injection design once the molding is made
• Complexity Scale: 1
• Complexity of Interactions: Simple design to start the engine by creating power
• Interactions Scale 2

Part: Clutch Shroud and Casing

• Complexity: Intricate design in plastic and holds clutch shroud to translate energy
• Complexity Scale: 2
• Complexity of Interactions: The casing protects clutch and the shroud takes rotational energy from the clutch and delivers it to the spring shaft
• Interactions Scale 3

Part: Washer

• Complexity: Simple 2 dimensional part
• Complexity Scale: 1
• Complexity of Interactions: Create spacing or make sure parts can move or not lock together
• Interactions Scale 1

Part: Head Spring

• Complexity: Simple design with great characteristics to retain shape
• Complexity Scale: 1
• Complexity of Interactions: Forces components apart or together but can be easily moved with the right force
• Interactions Scale 1

Part: Trigger Mechanism

• Complexity: Basic ergonomic design for the consumer to handle
• Complexity Scale: 2
• Complexity of Interactions: Controls the carburetor which controls the fuel input and the speed of the engine
• Interactions Scale 2

Part: Support Handle

• Complexity: Basic design for ergonomics and comfort for the consumer
• Complexity Scale: 1
• Complexity of Interactions: Attaches to spring shaft and is held by consumer
• Interactions Scale 1

Part: Air Filter and Casing

• Complexity: Molded shape easy to form and easy to take off the for consumer to clean the filter
• Complexity Scale: 1
• Complexity of Interactions: Cleans air for the engine to run smoother
• Interactions Scale 1

Part: Throttle Cable

• Complexity: Basic design with wires retaining strength
• Complexity Scale: 2
• Complexity of Interactions: Translates consumer input from the trigger to the engine to control fuel input
• Interactions Scale 2

Part: Key Piece

• Complexity: 2 dimensional product that can be easily mass produced
• Complexity Scale: 1
• Complexity of Interactions: Simple tool used to help control and balance flywheel
• Interactions Scale 1

Part: Muffler

• Complexity: Basic design with no overly intricate detail but multiple processes were used to manufacture this part
• Complexity Scale: 4
• Complexity of Interactions: Emissions from engine exit through muffler and create noise while the muffler dampens the noise produced.
• Interactions Scale 2

Part: Choke Plate

• Complexity: Basic stamped steel with bend end for handling
• Complexity Scale: 2
• Complexity of Interactions: Helps control fuel input when starting the engine
• Interactions Scale 2

Part: Kill Lever

• Complexity: Simple bent steel rod
• Complexity Scale: 2
• Complexity of Interactions: Instantly turns off engine when consumer turns lever
• Interactions Scale 1

Part: Spark Plug

• Complexity: In order to create a sparkplug there are many manufacturing processes that need to be performed
• Complexity Scale: 4
• Complexity of Interactions: Creates spark and ignites fuel to create power
• Interactions Scale 3

Part: Spring shaft

• Complexity: Multiple steps and layers needed to create the flexibility and strength needed
• Complexity Scale: 4
• Complexity of Interactions: Translates rotational energy from the crankshaft in the engine down to the head of the weed wacker
• Interactions Scale 3

Part: Shaft Housing

• Complexity: Hollow pipe cut and bent to shape
• Complexity Scale: 2
• Complexity of Interactions: Houses spring shaft and connects the engine to the main head of the weed wacker
• Interactions Scale 1

Part: Main Casing

• Complexity: Intricate detail inside and outside the plastic that surrounds the engine
• Complexity Scale: 1
• Complexity of Interactions: Protects the engine and the consumer from the engine
• Interactions Scale 1

Part: Head Guard/ Protective shield

• Complexity: Easily produced once mold is made
• Complexity Scale: 1
• Complexity of Interactions: Protects consumer from spinning line/blade and from debris
• Interactions Scale 1

Part: Elbow Spacer

• Complexity: Can easily be mass produced through die casting
• Complexity Scale: 1
• Complexity of Interactions: Keeps space between engine and housing to create a tight fit
• Interactions Scale 1

Part: Head Assembly

• Complexity: Multiple parts working together to house line
• Complexity Scale: 2
• Complexity of Interactions: Holding line and dispenses line to cut weeds
• Interactions Scale 2

Part: Head spacer

• Complexity: Circular pipe with small length
• Complexity Scale: 1
• Complexity of Interactions: Create space between shaft and head
• Interactions Scale 1

Part: Screws

• Complexity: After being casted the shaft of the screw is then sent through a set of rollers so that the threads can be applied to them.
• Complexity Scale: 2
• Complexity of Interactions: Holds two or more components together
• Interactions Scale 1