Group 11 - Weed Eater Featherlite 22C

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Group 11 - Weed Eater Featherlite 20CGroup 11 - Weed Eater Featherlite 22C
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Figure 1: Fully assembled view of the product. }}
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Name of Artifact Featherlite 20C string trimmer
Manufacturer Weed Eater
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Group 11 - Weed Eater Featherlite 20C String Trimmer

Contents

Work Proposal

Introduction

The purpose of the work proposal is to reveal how our group plans to reverse engineer a Weed Eater Feather Lite 20C. The disassembly and assembly of the product will need to be completely documented with what tools are required, what specific components the product gets broken down into, and how we will go about taking it apart. Our various tasks for each gate will be scheduled using a Gantt chart, so the group has solid deadlines to ensure that each member has advanced notice of when each section is due. In this gate we have analyzed individual strengths and weaknesses as well those of the group as a whole, and have determined individual roles according to the aforementioned abilities.

Capabilities and Challenges

Each group member has differing capabilities and weaknesses, and therefore will be assigned to do different tasks according to their specific strengths. We have divided each person’s responsibilities in order to make certain that each member of the group has the same amount of work load and that no one gets stuck doing more than other members. We may encounter a few challenges throughout the project, but with the different strengths among the individual members, we have experience in the various aspects of the project and thus do not expect too many challenges. Specifically, in our group two members have had experience taking engines apart and two other members have been around engine dissection. As a result, we are not expecting many problems, but if one comes up we will have the ability to figure out how to overcome the challenge.

Technical Communication

Although this project greatly depends on the physical hands-on dissection of the product, it also greatly relies on the ability to communicate the information gathered. Therefore, this project involves a great deal of technical communication, which includes 3D modeling, the ability to produce graphs and tables, and formatting. Each member of our group has previous experience with Microsoft word, Excel, and has recently been exposed to technical writing. Each group member will participate in writing up various sections for this project and will work together to compile them in a uniform manner. Since the information is presented on the wiki, formatting and the presentation of data is important. Modeling parts in AutoCAD will become a large component in future gates, thus Chris, who has the most experience in this field will become vital. Having to upload the final document into the wiki, Erika, who is proficient in organizing information, will be essential in formatting the text and visuals to ensure the technical report is written in the a professional manner.

Disassembly/Reassembly

Dissecting the engine into its individual parts and components is a major component of this project. The majority of the group has prior knowledge of engines and experience in dissecting them and examining how they function. Scott and Pete have taken apart engines and are familiar with the various tools that are needed for the process. Also Rob and Chris have had experience with tools and have seen the workings of engines and will be great assets in the disassembly/reassembly.

Management

Each group member will make important contributions to this project and will have responsibilities that they need to fulfill. However, stable management is vital to ensure that the group works together in a fluent manner and that tasks are getting completed on time. Rob has the role of manager and is responsible for making sure that all of the assigned tasks get completed in a thorough and timely manner that is up to the standards of the rest of the group.

Expected Challenges

Based on the strengths of our group, as displayed in Table 1, we do not anticipate many overwhelming challenges or obstacles in this project. We believe that our group will be able to function together in an efficient manner to be successful. However, the one major challenge we have determined will be a hindrance in our dissection and analysis of the product is the fact that none of the individuals in our group have much experience or knowledge with how real cars function. Since our product is a toy Ford Mustang car, a background in automobiles and how they work would be useful in our disassembly and reassembly of the car. It would allow us to make a better judgment as to which parts to remove first, based both on connection and function. Also, a knowledge of how a car functions would yield a better analysis of the product as a whole. This being said, we still believe that this is a challenge that we can overcome through the combined strengths and efforts of all six group members. While a background in the workings of a vehicle would assist in our dissection and analysis of the product, it is not essential in order for our group to be successful, especially since we can increase our knowledge through research and hands-on experience with the Ford Mustang.

Capabilities Chart

Table 1: Group Member Strengths and Weaknesses
Member Strengths Weaknesses
Robert Lang • Prior experience in dissections
• Technical knowledge of engines
• Time management and organization
• Proficient in AutoCAD
• Good public speaker
• Strong technical writer
• No experience with Wiki
• Revising
Erika Salem • Previous knowledge in using the Wiki
• Proficient in AutoCAD and Microsoft Excel
• Takes clear, detailed notes
• Time management
• Compiling work and editing
• Strong technical writer
• Limited experience in dissections
• Small knowledge of motors
Chris Mustacchio • Proficient in AutoCAD
• Technical knowledge of engines
• Previous experience in dissections
• Strong public speaker
• Works well in groups
• Time management
• No Wiki Experience
• Technical writing
Peter Sloan • Previous knowledge in the dissection of an engine
• Extensive knowledge of tools
• Strong public speaker
• Works well in groups
• Time management
• No experience with Wiki
• Technical writing
John Sommavilla • Previous knowledge in the dissection of an engine
• Thorough note taker/documenter
• Strong public speaker
• Works well in groups
• Time management
• No experience with Wiki
• Technical writing


Plan for Reverse Engineering of Product

We have outlined a plan in order to successfully disassemble the Weed Eater Featherlite 20C string trimmer. This outline will allow our group to dissect the product in a more timely and organized manner resulting in a better knowledge of the product and thorough documentation of the process.

Tools

Figure 2: GoPro HD Hero HD recording camera
Table 2: Dissection Tools
Tools Uses
Torque Screwdriver (t-20) Remove the outer casing in order to further view subsystems and disassemble them
Alan Wrench Size 5/32 Remove the handles
Philips Head Screwdriver (Size 1) Remove the air pump
Spark Plug Wrench Remove the spark plugs
Hammer Accompanies the screwdriver in the act of prying the casing of as well as forcing parts out of or back into place
Flat Head Screwdriver Pry apart pieces of the casing
Adjustable Wrench Remove the handle and blade shield
Safety Glasses/Gloves Protection when dissecting the product
Table 3: Documentation Tools
Tools Uses
Digital Camera Record each individual piece of the project dissection and use the pictures to aid in the reassembly, shown in Figure 2
Video Camera Record the dissection progress for use in the reassembly and in the final presentation
Notebook Reference for project notes - a place to write down important aspects of the project build

















Disassembly Process

1. Safety

The number one priority while doing any engineering process should be safety. We plan to uphold the highest quality of safety while disassembling and reassembling the string trimmer to assure that nobody gets hurt during the process. In order to get things done in a safe and efficient manner we will wake sure that we have a large selection of tools to choose from so that we can use the correct tool for it designed use rather than forcing things with a wrench. We make sure that all members are always wearing proper eye protection during the dissection process to assure that parts didn’t fly out into people’s eyes. The proper tools we will need for the disassembly, determined with no prior dissection of the product, are listed above in Table 2. One vital step that we had to take before disassembling the trimmer into its individual components was siphoning the fuel to make certain that the string trimmer cannot start and there is no flammable gas that can spill out. Our group will also make sure to use gloves to take apart the all of the parts after the casing was removed in order to protect our hands from the grease and lubricants that the engine secretes.

2. Outer Dissection

After we removed the fuel and made sure to follow all of the previously discussed safety procedures we can start to take apart the product. We will begin by removing parts that are not necessary for the product to function such as the blade shield, variable handle, and the engine casing. In order to remove these parts, we will use an adjustable wrench and torque screwdriver. After doing this we will remove the choke and air pump from the side of the product using a Philips head and the torque screwdriver. Lastly, we will remove the throttle handle using an Alan wrench. Removing these outer parts using the aforementioned tools, further described in Table 2, will provide a good view of the internal parts and subsystems of the product.

3. Subsystem Dissection

Once the outer housing is removed there are a number of individual subsystems that can be taken apart. The motor that runs the product is a FL20C, which we determined stood for Featherlite 20cc. Like most motors of this type we also concluded that it runs off of combustion and most likely runs off of one cylinder. Our first step for the subsystem dissection process will be to remove the fuel tank with our torque screwdriver and remove the fuel lines from the primer. Once the fuel tank and fuel lines have been removed we will remove the choke and primer system using the Philips head screwdriver followed by removing all of the electrical lines making sure to follow all of our safety procedures. After these subsystems have been removed we will remove the spark plug and the exhaust system from cylinder. Once all these systems have been removed the last components left will be the cylinder, crankshaft, and the crank casing. The cylinder can be easily separated from the crank casing. We can then crack open the cylinder we will most likely find a piston, gasket, connecting rod, and the crankshaft. We will then remove the crank casing using our torque screws and find spacing washers and the product’s flywheel. Now that the motor has been taken apart we can move onto the metal shaft. Inside the shaft we will remove the trigger and the trigger activation cable. On the bottom of the shaft there is the rotating cutting head, which we will remove with our Alan wrench revealing the end of the driveshaft. Finally we can remove the driveshaft from the metal shaft completely disassembling the string trimmer. It should be noted that all of the procedures previously listed are based solely on what we could see through the exhaust casing. Because these procedures were all based off of what we can see they might change slightly when we actually take the product apart and document it. Following the above process someone who is competent with motors should be able to take the product apart in about an hour and a half. Although taking the product apart will not take that long documenting all of the procedures is thorough and will take a great deal of time and possibly add another eight hours to our procedure. This is just an estimate of the amount of time our procedures will take so the time is subject to change and might take longer than anticipated. The time set for completion all depends on the small parts that are located within the cylinder and driveshaft that cannot be seen without dissecting the product. We also need to make sure that all of our documentation is precise and professional so this might also add some time onto the process.

4. Documentation

Each step of the product dissection will be documented using all of the tools mentioned in Table 3. We will be using the digital camera to take photographs of each of the components as well as of the product as we remove the different parts in order to correctly and easily reassemble it. The video camera will be used to film every step of the dissection to be later edited and used in our final presentation. The notebook will be used frequently by the head documenter to take thorough notes of the process to aid in the analysis of the product and in the final technical report.

Management Proposal

Introduction

In order to successfully and thoroughly complete the dissection project for the MAE 277 course, we as a group have devised a plan to equally divide up the work that is required for the completion. We have assigned different roles according to individual strengths and weaknesses in order to ensure that the project is done to the best of our group's ability. Meeting times and expectations are clearly outlined, which will result in little conflict between the group. The Gantt Chart, Figure 3, is an outline of when the various sections of the gates are due, which sets solid deadlines known to the entire group.

Point of contact

The group will be able to get in contact with each other and the professors through the following email: mae277group11@gmail.com

Meeting Times

We have established biweekly meetings to ensure that we have sufficient time tom complete each task and gate. These mandatory meetings will allow us to set more specific deadlines and make sure everyone is being accountable for completing their assigned tasks. Each meeting will consist of a meeting agenda of what we plan to accomplish that week; it is also where we will look over what each member has completed since the last meeting. Mandatory meetings are scheduled for Tuesdays and Thursdays at 4:00pm at 86 Winspear. This is an available time for every member of the group because it immediately follows our thermodynamics class. Having meetings at 86 Winspear is convenient because four out five members live on Winspear and we will be utilizing the garage at the house as our dissection room. The biweekly meetings will have no time limit on them and will last depending on the amount of workload for that week. This outline further specifies the positions held by each group members along with individual responsibilities.

Group Conflicts

If a group member becomes dissatisfied with their position, they can bring up their problem at the next group meeting. If a conflict arises with another group member, it can be anonymously documented through the group email and will be brought up by the project manager at the next group meeting. If there are multiple conflicts involving the same person, an emergency meeting will be called and the conflict will be brought to the attention of the professors.

Team Positions

Robert Lang
Project Manager, Assistant Wiki Editor
Erika Salem
Head Wiki Developer, Editor
Chris Mustacchio
3D Modeling Expert, Communication Liaison
Peter Sloan
Dissection Specialist, Editor
Scott Sommavilla
Head Documenter, Parts Technician

Position Description

Project Manager

The project manager is responsible for dividing up the tasks among the group members – this will be done according to the individual strengths and weaknesses of the group members. He is responsible for setting deadlines and ensuring that each gate gets completed thoroughly and in a timely manner.

Head Wiki Developer

The head wiki developer is the main contributor to the formation and development of the wiki account. She is responsible for communicating with the head documenter and the other group members to make sure that all information was documented.

Assistant Wiki Developer

The assistant wiki developer is accountable for assisting the head wiki developer in importing information into the wiki. He will help with the formatting and overall presentation of the information.

Head Documenter

The head documenter is responsible for thoroughly recording each stage of the dissection and therefore is required to be present during each section of the dissection process. He is in charge taking digital photos of the individual parts as they are examined.

Dissection Specialist

The dissection specialist is head of the physical dissection process. He works collaboratively with the product technicians to dissect and reconstruct the product with no damage to the parts. He will ensure that the proper tools are being used and that they are being used in a safe and productive manner. It is crucial that he stays in close contact with the head documenter to guarantee that all the information is being correctly recorded and it accurately embodies the product.

3D Modeling Expert

The 3D modeling expert is responsible to generating computer models of the various components of the engine that will be used in the technical report of the dissection. He will be present at the time of the dissections to obtain the measurements of the parts in order to create accurate and more realistic representations of the parts.

Communication Liaison

The communication liaison is the communication link between Phil Cormier and the group. She is also in charge of scheduling additional meetings and dissection times if necessary.

Parts Technician

The parts technicians serve to help in the physical dissection of the product. They are to listen to the dissection specialist for orders on what aspect of the product motor they are to dissect and which tools need to be used. Each member of the group is a parts technician because it allows them to gain hands-on knowledge of the product.

Editor

The editor is accountable for making sure the information in professional, presentable, and accurate. The group members will check over each other’s work before it becomes finalized and it is posted on the wiki account.

Gantt Chart

Figure 3: Gantt Chart

Preparation and Initial Assessment

Initially our group preformed an inspection of our product without doing any dissection. Based on mechanical, aesthetic, and other physical evidence, our group developed an assessment of the Ford Mustang Power Wheels Car. This assessment allowed the group to formulate a course of action in dissecting the product with the appropriate tools and procedures.

Product Development Profile

Product History

Weed Eater, an outdoor equipment company, was founded in 1971 by a man named George Ballas who wanted to create a string trimmer that would not harm the bark of the trees when the trimmer came into contact with it. In the late 1970s, Weed Eater merged with Poulan and together the company became a leading manufacturer in gas, electric, and battery powered outdoor equipment including lawnmowers, snow blowers, chainsaws, and string trimmers. The Featherlite 20C weed eater string trimmer is a gas powered trimmer that utilizes a 20cc 2-cycle engine. It features a fifteen inch cutting diameter as well as a single exit “Tap ‘n Go” or bump head. The Featherlite 20C weed eater was produced to trim the lawn in areas that the lawnmower cannot easily reach. Designed to operate in more rural and suburban areas, the weed eater would not be well suited to be used in cities because of its limited amount or lack of grass. Not constricted by a cord like an electric string trimmer would be, the Featherlite 20C weed eater can be used in a wider range of places from a household lawn to the lawn on the property of a school. One of Weed Eater’s main priorities in producing string trimmers is to ensure the use of comfort and safety. As a result, they have installed a padded handle on the shaft of the string trimmer as well as a safety shield on the user side of the head that blocks the cut grass and weeds from hitting and possibly injuring the user.

Economic and Global Concerns

While trying to produce a string trimmer that was both safe and user friendly, Weed Eater also designed the product to face economic and global concerns in order to make it as desirable as possible. Originally produced in the late 1970s, it was designed and manufactured with a gas engine because people were not concerned about the soaring gas prices as they are today. The low prices of gas that existed during that time made having a gas engine beneficial because the string trimmer has a small-sized fuel tank and requires little gas to fuel it. The product also costs less than most other string trimmers, but still does quality work making it very cost effective for the user. The line used for the trimming also has a tendency to break when it comes in contact with hard objects such as a fence or the side of a house in which new line will be released from the head until it runs out and a new spool of line has to be purchased. As a result, this string trimmer comes equipped with a bump line feed ensuring that no line goes to waste when being replaced making the spool of line last for a longer period of time. With various locations in Canada, the vast majority of Weed Eater locations are in the United States. As a result, Weed Eater has little concerns with global factors. Although the string trimmer runs off of a combination of gasoline and motor oil which would make it globally diverse, this specific company designs them to run solely off of 87 octane gasoline, which limits it use to North America. Further limiting it usage to North America, more specifically to the United States, the specifications are presented in English units.

Product Sales, Support, and Distribution

The Featherlite 20C, like all Weed Eaters is produced in the United States and Canada, and is manufactured to be sold solely within North America, mainly in the United States and Canada. While foreign consumers are able to purchase a Weed Eater, the vendors do not ship outside of North America and therefore an alternative method of shipping must be established. As a cost effective product, the Featherlite 20C is relatively cheap, but is intended to have a long life cycle and require little maintenance aside from replacing the line in the head of the trimmer. Further increasing the cost value of the product, Weed Eater trimmers come accompanied with a two-year warranty that covers any manufacturer defects that are encountered during usage and parts and labor that might be needed if damage is inflicted on the trimmer; however, any damager imposed on the trimmer due to the use of accessories not recommended by Weed Eater or improper maintenance is not covered.

Intended Impact on the Consumer and Society

The Weed Eater Featherlite 20C was intended to represent the best value to consumers by offering quality, power, and durability at a fraction of the price of trimmers manufactured by other companies. Getting in contact with a customer service representative of Weed Eater, she reiterated the saying that Weed Eater is “trimmer America asks for by name.” Manufacturing various models of 2-cycle gas trimmers, Weed Eater allows consumers to get professional quality without a high price tag. Addressing the problem of limited mobility that accompanies the electric string trimmers that must be plugged into a power source in order to work, the use of a gas allows for endless mobility by eliminating the need for a power cord. This provides the consumer with freedom to easily move around and utilize the product in a faster and more efficient manner. The string trimmer also ensures that the user remains safe and comfortable by installing a safety shield on the user side of the head and having a curved driveshaft making holding it at ground level and reaching into lower areas such as under a deck a great deal easier.

User Profile

Intended Use

The Weed Eater Featherlite 20C curved shaft gas string trimmer is used keep lawns aesthetically pleasing. In order to do so, the trimmer cuts or trims grass, weeds, and small plants positioned in areas of the lawn that are hard to reach with the use of a lawn mower. The trimmer does this with the use of a flexible line that is rotated around the head at the end of the shaft that is powered by an internal 2-cycle motor.

Home vs. Professional Use

This Weed Eater Featherlite 20C is a versatile product that can be utlized for both home and professional use, but is geared more toward home landscaping. This particular string trimmer is smaller in size and therefore is not well-equipped for the heavy duty use professionals might encounter. Mainly used for individual lawn care, the trimmer can be used by both men and women without difficultly because it is lightweight and easy to maneuver. For more heavy duty lawn care, the line in the trimmer can also be replaced with a plastic blade that allows the user to utlize the trimmer to cut or trim thick weeds or bushes.

Jobs Performed

The principal job performed by the string trimmer is trimming grass and weeds that are located in areas that are difficult to effectively reach with a lawn mower. A string trimmer is also known as an edger as a result of this main job – the trimmer is often used where the grass meets a house or fence. If the user replaces the line with a plastic blade the trimmer can also be used for more heavy duty jobs just as trimming such as trimming bushes or large weeds.

Energy Profile

The energies involved with this process would be chemical energy from the fuel, along with physical energy from human involvement. The physical energy from humans is transferred through the machine in the form of holding the machine up, as well as controlling the speed and direction of the cutting head to do the actual work of cutting the grass. The other energy input comes in the form of chemical energy from gasoline. The energy of gasoline is harnessed in the form of combustion, when the gasoline and oil mixture is ignited, and the pressure from the explosion is transferred to mechanical energy when the force moves the piston, rotating the crankshaft, which spins the rotating cutting head.

Complexity Profile

Figure 4: An exploded view of the parts that make up the engine of the string trimmer

The overall complexity of the machine is not very high, when being compared to a machine such as a watch, where exponentially high levels of precision are needed. The weed eater is composed of a few different sub systems that are very complex, but not that hard to understand and understand how they work and play a role in the functionality of the weed eater. Overall all the sub systems of the weed eater are complex in how they are made and how they fit together with each other; however, understanding all of the sub systems is very easy to see and learn how they go together.

Engine

The engine is composed of different aluminum parts, which serve every purpose from fuel intake to exhaustion. The carburetor has an air and fuel inlet, and is connected on one side of the motor. There are adjustable fuel nozzles, or “jets” inside of the carburetor to adjust the flow of fuel into the motor, but with a motor this small and with a performance value, there is no great need to fine-tune the motor. The motor itself is composed of the block, which is the bottom end of the motor, used as a housing to handle the crankshaft and support the head. The head is a cubic block of metal with fins on the external side to maximize heat dissipation. The internal part of the head has a cylinder bored out to allow for the piston. The piston moves within the cylinder, pushing and pulling on the crank, causing the crankshaft to rotate. The crankshaft is an offset rod, which is rotated as the crank moves up and down with the cylinder. Every time the cylinder moves upward, an electrical current is sent from the ignition box through the spark plug, igniting the end, allowing for combustion. The exhaust manifold is connected to the other end of the motor, and provides a channel for the hot exhaust gasses to be safely expelled.

Drive Shaft

This particular model has no clutching system, meaning that the drive shaft is directly connected to the crankshaft. Because if this, the cutting head will be rotating whenever the motor is operating, and will change speed when the motor does so. The drive shaft is most likely a steel-braided cable, which is housed inside a curved aluminum tube. The drive shaft is connected to the crankshaft on one end, and the cutting head on the other, allowing the kinetic energy from the motor to be transferred to the cutting head, and eventually to whatever is to be cut.

Cutting Head

The cutting head is mounted at the end of the drive shaft and houses the nylon cutting line used to cut the grass. The head consists of two “bell” shaped plastic pieces, with a spring connecting the two in the middle. The cutting line is fed through a hole on either side and is wound around the center within the bells. When the line is cut too short, the operator much tap the cutting head against the ground, decreasing the tension in the spring, allowing for the line to be fed out until a desired length.

Housing

The housings on the machine all consist of plastic, molded into different shapes to fit desired positions. There is a line guard that wraps around the path that the cutting line travels in, in order to protect the operator from flying debris and cutting line. The motor housing is a combination of two plastic parts, screwed to the motor and mounts, yet sit far enough off of the motor as to not heat up. This barrier prevents the operator from inadvertently coming in contact with the motor, which could potentially cause serious injury.

Material Profile

Clearly Visible

The materials seen overall in the product are various, however appears to be limited to only a few. The primary material seen in the String Trimmer body is plastic. The spinning cutting head, the string guard, the handle, the throttle lever, on/off switch, the engine housing, fuel tank, gas cap, and carburetor housing are all composed of plastics, of varying colors and chemical composition. The next most plentiful material in the construction is aluminum, which is used in the composition of the drive shaft housing, as well as the engine block, head, carburetor assembly, and exhaust manifold. The starter cable, along with the trimming line is made of different types of nylon. The last type of material found visibly in the trimmer system is rubber, which composes the primer bulb, fuel lines, and spark-plug wire. The above listed are materials visible.

Not Visible

The materials that are believed to be present, yet are not visible are consistent with the ones visible. The internal motor parts, including the piston, crank, crankshaft, and spark plug are composed of aluminum. The drive shaft is most likely made out of a steel braded cable, or reinforcement with flexibility required in a curved shaft-trimmer.

User Interaction Profile

Usage

The product’s user interface is simple; the user controls every aspect of the operation. The machine requires a mixture of minimum 87 octane gasoline and two-cycle oil for ignition and lubrication. The operator must mix the fuel, fill the fuel tank, and start the machine via the pull cord. From there, the user must hold up the machine and aim and whatever is desired to be cut, as well as control the throttle. The product is very simple to use, requiring only start-up procedures listed above and simply walking with the machine. The user interface is not intuitive by any means because the product is not designed that way. The objective when designing the product was to produce a product that is simple to use and incredibly lightweight. Because of this, every component is manual, giving the user total control, and the machine as little as possible.

Maintenance

The engine of the machine is a small, single cylinder, two-cycle engine, which requires very little maintenance. Two-cycles do not require any oil changing, and with the relatively small amount of moving parts, compared to four-cycle engines, there is very little wear-and-tear, which means that nothing should need replacement over the lifetime of this machine. The only issue with a two-cycle engine is fouling of the spark plug, which would only occur if the operator added too much oil when mixing the fuel. The only other common problem among two-cycle engines would be the fuel gumming up over long period of discontinued usage. In order to prevent this, the operator must “winterize” the motor by running a fuel stabilizer through the motor by way of mixing it with the fuel on the last operation before discontinued use. Besides the motor, the only moving part in the line-of-action is the drive shaft and cutting head. The required maintenance for upkeep on the shaft is lubrication in the form of greasing annually.

Product Alternative Profile

Existing product alternatives

Since there are various companies that manufacture string trimmers of different models, there are numerous alternatives to the Featherlite 20C (20-cc) Weed Eater that perform the same task. String trimmers can vary in different aspects including weight, cost, comfortableness, and the ability to do heavy duty work. A similar string trimmer manufactured by Weed Eater can be purchased for a similar price, but similar string trimmers manufactured by other companies tend to be more expensive in price, but may offer additional features such as being quieter and having less vibration. An alternative to gas string trimmers, not explicitly the Weed Eater Featherlite 20C, is electric string trimmers. Although electric trimmers are cheaper in price, gasoline trimmers provide more freedom of usage because they do not have an electrical cord that limits its motion. Gasoline string trimmers also tend to be more powerful allowing them to do more heavy duty jobs. The specific Weed Eater alternative to the Featherlite 20C is the larger and more powerful Featherlite 25. Various other alternatives from the numerous other companies include: Craftsman Convertible 25-cc 2-cycle curved shaft Gas Trimmer, Husqvarna 122C curved shaft string trimmer (21.7-cc), and Echo GT-200R curved shaft trimmer (21.2-cc).

Product Advantages

As previously mentioned, the Featherlite 20C Weed Eater provides the user with endless mobility because it is not limited by the length of an electrical cord. This provides the consumer with freedom to easily move around and utilize the product in a faster and more efficient manner. This two-cycle engine provides the user with easy maneuvering because it is smaller in size as well as lightweight. Although it is heavier than an electric trimmer, this string trimmer provides greater power for its size. Furthermore, this trimmer is less strenuous when being used because it has a curved driveshaft making holding it at ground level a great deal easier than if the driveshaft was straight as well as makes it easier to reach into lower areas such as under a deck or some bushes. Ensuring the safety of the consumer while using the product, the head contains a safety shield on the user side that blocks the cut grass and weeds from hitting and possibly injuring the user.

Product Disadvantages

Although the initial cost of the Featherlite 20C Weed Eater is cheaper than that of an electric trimmer, the cost of fueling it with gasoline mixed with motor oil becomes expensive especially during recent times. The two-cycle engine creates loud noise and a notable amount of vibration that limits the amount of time it will be used because it makes carrying the device tiring for the user. The use of a gas-powered engine also has negative environmental effects because it releases emissions into the air that contribute to the overall greenhouse gases harming the atmosphere.

Comparison Between Alternatives

The alternative string trimmers are similar in that they all function using a two-cycle engine, have curved shafts, and have bump head systems. Each of the string trimmers also comes with a loop handle as shown in figure ____ that allows for easy maneuverability. They also have very similar values in cutting swath, mainly being sixteen inches. Although they are very similar in weight, the fluid capacity varies from 12.2 fl oz in the Husqvarna 122C to 14.9 fl oz in the Echo GT-200R, the driveshaft length varies from 48 inches for the Echo GT-200R and 54.4 inches for the Weed Eater Featherlite 25. Overall, these alternatives are decently easy to compare given the information provided on each specific brand and model.

Differences in Cost

The prices among the alternative products vary greatly from $95.99 for the Craftsman Convertible 25-cc 2-cycle curved shaft Gas Trimmer to $159.99 for the Echo GT-200R curved shaft trimmer, but all alternatives are more expensive than the Featherlite 20C Weed Eater, which runs for around $60. Although the products seem to be very similar to one another, durability and the degree of heavy duty jobs that can be done play a significant role in the consumer’s decision of which make and model to purchase. With the information given this cannot be determined, one would have to do additional research to conclude whether the more expensive string trimmer has advantages of the lower priced trimmers.

Table 4: Comparison of String Trimmers
Model Manufacturer Cost Cut Path Weight Image
Featherlite 20C[1] Weed Eater $55.00 15 in 12 lb FL20.jpg
Featherlite 25C [2] Weed Eater $65.00 16 in 12.15 lb FL25C.jpg
122C [3] Husqvarna $149.95 16 in 9.7 lb 122C.jpg
GT-225 [4] Echo $159.99 16 in 10.2 lb GT225.jpg
Convertible 25-cc [5] Craftsman $95.99 16 in 11 lb Convertible.jpg

As seen from Table 4, almost all of the products have the same cut path range. The more expensive string trimmers are the ones that are lighter in weight. If buyers want a lighter string trimmer, they have to pay the higher price.

References

[1] "FL20C Product Specifications." Weed Eater. Web. 1 Oct 2011. <http://www.weedeater.com/node7828.aspx?nid=211397>.

[2] "FL25C Product Specifications." Weed Eater. Web. 6 Oct 2011. <http://www.weedeater.com/node7828.aspx?nid=374536&pid=135661>.

[3] "Husqvarna 122C." Husqvarna Products. Web. 6 Oct 2011. <http://www.husqvarna.com/us/homeowner/products/trimmers/122c/>.

[4] "Echo GT-225." Echo. Web. 6 Oct 2011. <http://www.echo-usa.com/Products/Trimmers/GT-225>.

[5] "Lawn and Garden Line Trimmers." Craftsman. Web. 6 Oct 2011. <http://www.craftsman.com/craftsman-convertible-trade-25-cc-2-cycle-curved-shaft-weedwacker-trade-gas/p-07179102000P>.

[5] "User's Manual."Weed Eeater Featherlite. Web. 9 Oct 2011. <http://www.weedeaterfeatherlite.com/manual>.