Gate 1 (group 8)
Overview of Plan
Group number eight was given the task in taking apart a broken Black and Decker Jigsaw. All five group members are planning to meet on the weekend of the 16th of October to disassemble this product. Chris Fernandes has a good background in dissecting appliances and has volunteered to be the lead in taking apart the Black and Decker jigsaw.
The exterior of the product only consists of screws in which a Phillips head p2-418wpr screwdriver must be used in order to disassemble it. The interior of the product will also need the Phillips head p2-418wpr screwdriver in order to remove the remaining parts. The group has predicted that this screwdriver would be the only tool needed in order to completely disassemble the product. If more tools are needed Agnelo has volunteered to provide them because he has a large tool chest and thus, was appointed Chief of Materials for this reason.
The group has researched the components of the Jigsaw and has predicted that it will not take more than fifteen minutes to take apart. The eight exterior screws will take roughly three minutes to unscrew and remove, and the internal components will take the remaining twelve minutes. The group has predicted that there will be fifteen main internal components that will have to be taken out in order to complete this.
Group Capabilities and Shortcomings
As Chris takes apart the jigsaw, one member will make a video recording of the process, while the other members will document observations. He will also be the lead person for the CAD drawing because he is currently taking Mae377, which Agnelo is goignt to be the main person dealing with Wikipedia. Group number eight has had a few discussions about the strengths and weaknesses of its members and everyone seems capable of executing the tasks required. Suengkuk was brave enough to admit that he is not strong in the English language so the rest of group 8 has volunteered to help with proof reading his portions of the assignment. Overall the energy of group eight is positive and we expect everything to run smoothly.
Overview of Plan
The members of group eight has had many discussions about how they were going to manage their time. The group has worked so far by dividing projects into equal portions in order to complete assignments. This technique will also be applied to the final project but with each person doing tasks that they are good at.
Roles and Responsibilities
Ajmer Samaroo has chosen to be the group’s leader and his email address is email@example.com. He will specify due dates for individual portions of assignments so that he can proof read them before printing. He is also the lead communications person, sending emails to the group so they can meet and also to keep the members updated about how the project is coming along. Chris Fernandes is leader on dissection and the CAD drawings. Agnelo is the lead Wiki person, and Seungkuk is head of research. The oral presentation will be conducted by Ajmer, Chris and Agnelo, with Agnelo taking the lead because of his clear tone of speech. The written report would be split between all five group members.
There are a few conflicts that might have to be resolved in the future. For example if someone has an exam, or some unexpected problem that has arisen during a weekend when the group is supposed to meet, that date will then be changed in order to accommodate this problem. Since the Jigsaw only needs the Phillips-head screwdriver to dissemble the whole product, there should not be any problems with extra tools. If this problem arises, Agnelo will provide extra tools because he has a tool chest. If there are any other problems that the group comes across, the entire group will pitch in equally to solve them.
Dissection will take place on the weekend of the 16th of October and the required questions will also be answered on that weekend by all group members so that the assignment would be ready for the 30th of October. The group will then meet on the weekend of the 13th of November in order to complete the ‘Production Documentation and Analysis’ assignment, which is due on the 30th of November. This assignment would be split equally between all members with Chris Fernandes being the head of the CAD drawings. If we come across any problems, Seungkuk will be the main person conducting research for solutions to problems mainly because he is very effective at it. The group will then meet the following weekend of the 20th of November in order to polish up this part of the assignment and discuss the tasks for the ‘Critical project Review’ assignment due on the 12th of December. Since our Jigsaw was broken from the start our main goal with the assembly is to get the product working again. Again all members will work collectively in trying to find a solution for this part of the assignment. The group will then meet on the weekend of the 4th of December in order to complete this and start on the ‘Final Report Submission and Oral Presentation’ assignment. At the end of this weekend, the group is hoping to completely finish the entire final project so all that would be needed is a review and submission. With this outline, and every member doing his portion of the assignment, group#8 will be very successful in completing the final project.
The Black and Decker jigsaw is commonly used for cutting wood, metal and plastic. This product can be used for both home and professional uses. At home, the jigsaw is commonly used to make simple furniture such as tea tables or chairs. For professional use, carpenters can use the Jigsaw to shape spindles for a stairwell. It can also be used on multiple surfaces, making straight or curved cuts in wood, plastic and metal. The Jigsaw might be heavy compared to manual saws but the preciseness of its cuts make up for it. It allows users to change the blades easily, and provides enough power to finish tough tasks. Its integrated laser guide also helps users to cut the material accurately.
ENERGIES OF THE JIGSAW
Types of Energy Used
The Jigsaw uses two main types of energy for its operation: kinetic and electrical energy. The most important parts that utilize these energies are the field assembly (stator) and the armature.
Mean of Energy Transformation
The electrical energy flows to the field assembly which is the stationary part of the motor. The main function of the field assembly is to generate a magnetic field from the input current. This is done by the coils around the stator which allows a slip right process that transfers high voltage, low current to the rotation field coil. The armature now becomes an electromagnet which has a north and south pole which are repelled by the north and south pole of the field assembly. As soon as it completes a half turn the carbon brushes flip the magnetic field and complete the rotation. The Armature then generates the torque which moves the gear attached, which then moves the shaft assembly vertically up and down to move the blade.
FUNCTIONALITY OF THE JIGSAW
How well does the product run
When group eight uplifted the Jigsaw from the lab, we noticed that it was not working nor did it have a blade. Based on its reviews and Black and Decker’s reputation in the power tool market, the product should actually run and function very well but the product we have does not run.
Where are any problems coming from
When the product was plugged in to test its functionality it did not respond at all which lead us to assume that some of the interior components/parts are missing. The saw-blade and lock on button are also missing from what is visible without dissection. As the variable speed switch is already pushed all the way inside, the product is supposed to be running at full speed. The main problem is that the product does not start and it has not been dismantled yet. Therefore a complete diagnostic of the product could not be performed. Problems may be coming either from the interior of the product or the power cable. Some assumptions can be made as to why the product will not start; a) Circuit fuse may be blown. b) Cord or switch is damaged
COMPLEXITY OF THE JIGSAW
Complexity is defined as being hard to understand. The Jigsaw has many interconnected parts that might seem complicated compared to a manual saw upon a first glance, but after studying might seem better to understand.
Number of Components
The Jigsaw is made of the basic external components:
1) Lock-On button
2) Variable speed control-button
3) Saw-blade Locking lever
4) Saw-blade support roller
5) Saw blade
6) Shoe plate
7) Shoe plate locking Knob
8) Saw blade storage compartment
9) Dust blower
10) Power cable
From a bit of research the Jigsaw contains the complex internal components
11) Armature Assembly
12) Field Assembly
13) Brush and Spring
14) Gear Assembly
15) Shoe Assembly
16) Shaft Assembly
17) Brush Box
The above parts are considered complex because they are all interconnected parts with wires that would require some amount of studying before removing because one mistake with any of these parts would stop the Jigsaw from working altogether.
Below is an explanation of how the parts of the Jigsaw work.
1) The Lock-on Button: This is a handy tool used for locking the switch whether in an on-off position.
- If the switch is in the “on” position the lock button can be used to lock the switch, so that the user doesn’t have to apply continuous pressure or keep the desired speed using the “Variable speed control button”.
- If the switch is in “off” the Lock button can also be used as a safety switch which is installed as a safety feature by the Black and Decker Company
2) The Variable Speed button: Black and Decker has installed a handy button that allows the user to control the speed of the blade as it cuts through wood or thin metal.
3) Saw-Blade Locking Lever: This lever is used to lock the saw blade in position for a clean, crisp cut along the desired surface.
4) Saw Blade Support roller: The Blade support roller is used to support the blade’s displacement.
5) Saw Blade: Not a very complex part but one of the most important ones. It is specifically designed to provide effective cutting along the surface while working in unison with the other parts like the motor etc.
6) Shoe Plate: This component provides stability to the product while functioning.
7) Shoe Plate Locking Knob: This part is used for adjusting and tightening the shoe plate.
8) Saw blade Storage Compartment: This compartment is a handy little accessory for storing the different saw blades a user may have for different cutting situations or for storing spares.
9) Dust blower: This component is used to clean the surface of any dust fragments on the surface.
10) The Power Cable: Provides ample power for the power tool.
11) Armature Assembly- Is the motor and all of its components.
12) Field Assembly- A component that provides power for the motor to rotate
13) Switch Assembly- A control switch for moving the blade
14) Brush and Spring- Is used to transmit power to the Field Assembly
15) Gear Assembly- Is attached to the motor to help move the saw
16) Shoe assembly A plate for the user to push down on to keep the tool steady
17) Brush Box- Brush and Spring Holder
The Black and Decker Jigsaw is made of various materials most of which are hidden underneath the external casing. Observing the product, it can be deduced that the main product components and the materials used to make them are as follows.
Clearly visible materials
The visible components which are located in the outer casing, made up of bright red-orange heavy duty plastic with a rubber grip handle, .The casing is made by injection molding. The trigger, trigger lock, buttons, and company logo are made of dark colored plastic.The blade is made of high-speed steel and the Sightline, which provides accuracy and improves visibility, is made of aluminum. The unit also includes a power cable made of plastic and copper.
Materials that are not visible from an external inspection
The components that are not visible without disassembly are:
• Internal wiring (plastic, copper),
• Screws (steel),
• Gear system (copper),
• Motor (steel, plastic, copper),
• Cooling fan (copper).
• Grease/ oil
USABILITY, COMFORT, and SERVICEABILITY
The jigsaw is suitable to be used in a typical home. It has enough power and durability to be used for small scaled commercial purposes. It is ergonomic, comfortable and powerful.
The product is very comfortable to use. It has a rubber grip and contoured trigger that fits comfortably in our hands. The size of the product makes it durable and helps cause less fatigue while using it and it does not feel very heavy as well.
Ease of use
The jigsaw is very easy to use. The buttons are clearly labeled and anyone with or without knowledge of jigsaws can operate it. The procedures for the replacement of the blades are easy to learn as the custom clamp is specially designed for the purpose of quick replacement of blades.
The product does not require regular maintenance and most parts are easily replaceable if damaged.
The Black and Decker type 2 Jigsaw has several competitors in the market that closely compete with its performance and cost. Two such alternatives are the Craftsman17235 and the Hitachi CJ110MV.
A) The Craftsman17235 costs the same as our product and many of its components are basic with the exception of a more powerful motor. The Hitachi CJ110MV is nearly double the price of our jigsaw and the product is much more complex.
B) The Craftsman17235 has a 4.8 Amp motor while our product has only 4.5 Amps so it packs more power for cutting. It also has a built in LED light for precision viewing. The Hitachi CJ110MV is much more powerful than both of these devices and is built for more durable applications.
C) The Craftsman17235 is not ergonomic and the body feels heavier to use. It lacks the durability and precision of our product. The Hitachi CJ110MV lacks a dust blower. Also, none of the alternatives has its own wireless supply source despite their price.