Group 29 - Black and Decker Jig Saw

Black and Decker Jig Saw

Executive Summary

Hi guys! -=] working on it. fixed some grammars in other parts too. please freely add/correct my grammar and additional sentences.

Power drills are common tools necessary in any kind of construction.

My group fully disassembled a Black & Decker Jigsaw and examined all the different parts it was up of. We found out what kind of materials were used and how those materials were manufactured. Prior to the disassembly, we guessed what it's usage was, took an educated guess on how many parts the jigsaw consisted of, and assumed its features and how it works.

---testing testing 123 not done---

Introduction

The Black and Decker Jigsaw is a power tool used to cut sharp turns, with the ability to switch blades very simply. We dissected the jigsaw, named each part and analyzed the saw completely.

Our group equally worked on the project and consisted of the following members:

Mike Fama

Craig Castiglione

John Kresconko

Rex Chan

Ryan Spies

Pre-Disassembly

Purpose of the Jigsaw

The purpose of the Jigsaw is to cut different intricate bends into a piece of thin wood. The Jigsaw has the capability to cut sharp curves and turn at a small radius, where most saws only allow you to cut in straight lines.

Operation

The Jigsaw receives AC power from a wall outlet from which it is supplied to the motor. The motor then creates rotational mechanical energy which is then converted through a series of gears to produce linear motion/energy. This energy allows the blade to move up and down rapidly when the trigger is activated.

Amount of Components

Estimated number of components:

1. Screws
2. Casing
3. Cutting Deck
4. Blade Holder
5. Gel Pad
6. Trigger
7. Wiring
8. Motor
9. Gears

Types of Materials

Estimated types of Materials:

1. Steel
2. Plastic
3. Rubber
4. Copper
5. Gel

Disassembly

Disassembly Process Table

Step Number	Process	Tool	Level of Difficulty
1	Remove 7 Phillips-head screws	Phillips-head Screwdriver	Easy, 1 Screw Quite Difficult
2	Removed Rip Fence Bolt to Saw Blade Locking Lever	By Hand	Easy
3	Removed Removed Dust Blower Angle off of Dust Blower	By Hand	Easy
4	Removed Dust Blower and Rip Fence off of Casing	By Hand	Easy
5	Removed Rip Fence off of Casing	By Hand	Easy
6	Removed Plastic Blade Guard off of Casing	By Hand	Easy
7	Removed Casing off of Casing	Philips-head Screwdriver	Moderately Easy
8	Removed Gel Max Comfort Grip off of Casing	By Hand	Easy
9	Removed Shoe Plate Locking Gear off of Casing	By Hand	Easy
10	Removed Shoe Plate Locking Knob off of Casing	By Hand	Easy
11	Removed Trigger Switch off of Casing	By Hand	Easy
12	Removed Lock on Button off of Trigger Switch	By Hand	Easy
13	Removed Lock Spring off of Lock on Button	Flat-head Screwdriver	Easy
14	Removed Plastic Lock Washers off of Lock on Button	Flat Head Screwdriver	Moderately Difficult
15	Removed Switch Breaker off of Trigger Switch	By Hand	Easy
16	Removed 2 Cord Clamp Screws off of Cord Clamp off of Casing	Phillips-head Screwdriver	Easy
17	Removed Red Motor Connecting Wire off of Spring Loaded Graphite	By Hand	Easy
18	Removed Black Motor Connecting Wire from Spring Loaded Graphite	By Hand	Easy
19	Disassembled Spring Loaded Graphite Internals	By Hand	Easy
20	Removed Motor Screw From Casing	Philips-head Screwdriver	Easy
21	Removed Red Motor Connecting Wire From Armature	By Hand	Easy
22	Removed Black Motor Connecting Wire from Armature	By Hand	Easy
23	Removed Metal Gear From 1/4in. Plate	By Hand	Easy
24	Removed 1/4in. Metal Plate from Armature Shaft With Rotar	By Hand	Easy
25	Removed Small Metal Plate off of Armature Shaft With Rotar	By Hand	Easy
26	Removed Linear Oscillator from Metal Gear	By Hand	Easy
27	Removed Washer off of Gear from Metal Gear	By Hand	Easy
28	Removed Cylindrical Slider from Linear Oscillator	By Hand	Easy
29	Removed Blade Changing Piece from Blade Changing Component	By Hand	Difficult
30	Removed Blade Changing Spring from Blade Changing Component	By Hand	Easy
31	Removed Allen Wrench Screw from Blade Changing Component	3/32 Allen Wrench	Easy
32	Removed Blade Changing Component from Linear Oscillator	By Hand	Easy
33	Removed Felt Piece from Linear Oscillator	By Hand	Easy
34	Removed Cylindrical Slider 2 from Linear Oscillator	By Hand	Easy

Parts

Part Table

Part #	Part Name	Quantity	Material and Reason for Choice of Material	Function	Reason for Shape	Manufacturing Process	Image	CAD Crawings
1	Casing Screws	7	Steel which is needed for a sturdy screw	Holds casing and parts inside casing together	A good design to pull two pieces together	Machined
2	Saw Blade Locking Lever	1	Steel because it needs to withstand twisting and direct force.	A bar to keep the rip fence sturdy	To lock in on many points along the bottom	Machined
3	Rip Fence Bolt	1	Steel because bolts need to be strong enough to endure twisting and regular force	To hold the rip fence onto the casing	So it can pull two objects together	Molded then Machined
4	Dust Blower Angle	1	ABS Plastic because it does not take a lot of wear and tear. Also it is cheap and easy to make	To be a pathway for sawdust and air when a vacuum is attached	To turn so the angle can pick up sawdust directly off of what is being cut	Injection Molded
5	Dust Blower	1	ABS Plastic because it does not take a lot of wear and tear. Also it is cheap and easy to make	To be an opening for the pathway which the dust will flow through	To be an opening so it can pick up dust and be pressure fit to the rip fence	Injection Molded
6	Rip Fence	1	Steel because the bottom will be rubbed and hit as it is used quite often	To provide a guide and a base with which to push down on and move the blade	It is flat so it is easy to push and guide the blade along it's path	Injection Molded, Machined
7	Right Side Casing	1	ABS Plastic because it is durable and when it is thick it can deal with a lot of abuse and punishment	To hold all the parts together along with screws	To hold all parts in one area and keep them from moving in ways they aren't supposed to	Injection Molded
8	Left Side Casing	1	ABS Plastic because it is durable and when it is thick it can deal with a lot of abuse and punishment	To hold all the parts together along with screws	To hold all parts in one area and keep them from moving in ways they aren't supposed to	Injection Molded
9	Plastic Blade Guard	1	Plastic because it is a part you look through to see the blade and to protect a persons hand from the blade	To guard the front of the blade so nothing hits the blade that is not supposed to	to cover an area to make it inaccessible to hands and fingers	Injection Molded
10	Gel-max Comfort Grip	1	Gel because it gives and helps absorb the vibrations of the jigsaw	To comfort the hands of user	To cover and area where the users hands would be	Manufactured
11	Shoe Plate Locking Gear	1	Plastic because it is cheap and easy to make and the part does not take much punishment	The person spins it to lock the rip fence in place at a certain angle	It is a gear with teeth to turn another gear locking the rip fence	Injection Molded
12	Shoe Plate Locking Knob	1	Plastic because it is cheap and easy to make and the part does not take much punishment	The person turns the knob with their fingers to lock the rip fence in place	It is a gear and knob with teeth to turn another gear to lock the rip fence in place	Injection Molded
13	Trigger Switch Component	1	Plastic, Copper, Steel, Aluminum because all these are need to get current to flow through it into the motor	To control rate of flow of current to the motor	It is made so there is a constant flow and path of a certain amount of current to the motor	Manufactured
14	Lock on Button	1	Plastic because it is cheap and easy to make and the part does not take much punishment	It locks the trigger so that it cannot turn the engine on	It has two sides so it can be pressed and a small dash in the middle so it can block the trigger	Injection Molded
15	Lock Spring	1	Steel to make a durable and strong spring	It helps make moving the locking trigger easier	It is made in the spring shape to force an object in one direction	Manufactured
16	Plastic Lock Washers	2	Plastic because they do not get much force on them and it is cheap to make	It is to be put on either side of the spring and holding it there	It is made to hold the spring so it will not slip and be wide enough so all the force will be transfered	Injection Molded
17	Switch Breaker	1	Aluminum because it is conductive to metal and will melt breaking the circuit if to much current flows through	A circuit breaker that causes the jigsaw to stop working of too much current starts to flow through it	It is cheap and melts at relatively low temperatures and can handle current going through it	Machined
18	Cord Clamp Screws	2	Steel because they need to be durable and withstand the torque and shear force	To push down on the cord clamp to hold the cord in the casing	It was made to pull the cord clamp against the cord	Machined
19	Cord Clamp	1	Steel because it needs to be strong and is pushed against things	The screws push on it and then it in turn pushes on the cord to keep it in the casing	it was made that way to push evenly on the cord and near flat to save on manufacturing costs	Injection Molded, Machined
20	Red Motor-connecting Wire	1	Rubber and Copper which are great insulating and conducting properties	It conducts electricity from the trigger to the motor	It is made to conduct electricity as efficiently as possible and the rubber to insulate it	Manufactured
21	Black Motor-connecting Wire	1	Rubber and Copper which are great insulating and conducting properties	It conducts electricity from the trigger to the motor	It is made to conduct electricity as efficiently as possible and the rubber to insulate it	Manufactured
22	Spring Loaded Brushes	2	Plastic, Copper, Graphite because they are what is used for a AC to DC motor	It changes electricity from AC to DC	It is made because those materials are needed for the translation of AC to DC	Manufactured
23	Motor Screw	1	Steel because of high stress and torque put on it	It helps hold the motor to the casing	It pulls the motor onto the casing and holds it there	Machined
24	Armature	1	Steel, Copper, ABS Plastic to be durable and cheap	This part is the inside of the motor and a fan to keep the sawdust away	They are all made to do each job as efficiently as possible	Machined
25	Metal Gear	1	Steel for it's durability	It is turned by the motor and spins	It is a gear and helps turn other parts of the jigsaw	Machined
26	1/4 Inch Metal Plate	1	Steel for it's durability	Helps keep everything in place	It was made thick and strong due the vibrations and forces that act upon it	Machined
27	Small Metal Plate	1	Steel for durability	To help hold everything in place	Made thin because it vibrates and is used to protect the large plate from abrasion with a large amount of grease between each of them	Machined
28	Armature Shaft with Rotor	1	Steel, Copper, ABS Plastic, Tape	Part of the motor that alternates to turn the inside causing the rotation	Made to turn electrical energy into mechanical energy	Machined
29	Linear Oscillator	1	Steel for durability	Oscilates up and down moving the blade	In this form it is highly durable and can move easily	Machined
30	Washer off of Gear	1	Steel			Machined
31	Cylindrical Slider	2	Steel			Machined
32	Blade Changing Piece	1	Plastic			Injection Molded
33	Blade Changing Component	1	Steel			Cast
34	Blade Changing Spring	2	Steel			Manufactured
35	Alan Wrench Screw	2	Steel			Machined
36	Felt Piece	1	Felt			Manufactured

Product Improvements

Battery Operated

- Cord can be a safety issue

- Hampers mobility

- Limits use to within a certain displacement of an outlet

Insulate Plastic

- Saw runs loud

- Insulating plastic will reduce noise

Laser Guide

- Help provide more accurate cutting

Increase Amount of Gel Max Comfort Grip

- With long use more gel will maintain comfort

Assembly

Assembly Process Table

Step Number	Process	Tool	Level of Difficulty
1	Attach Cylindrical Slider 2 to Linear Oscillator	By Hand	Easy, 1 Screw Quite Difficult
2	Attached Felt Piece to Linear Oscillator	By Hand	Easy
3	Attached Blade Changing Component to Linear Oscillator	By Hand	Easy
4	Attached 2 Allen Wrench Screws to Blade Changing Component	3/32 Allen Wrench	Easy
5	Attached Blade Changing Spring to Blade Changing Compenent	By Hand	Easy
6	Attached Blade Changing Piece to Blade Changing Component	By Hand	Easy
7	Attached Cylindrical Slider to Linear Oscillator	By Hand	Easy
8	Attached Washer of Gear to Metal Gear	By Hand	Easy
9	Attached Linear Oscillator to Metal Gear	By Hand	Easy
10	Attached Small Metal Plate to Armature Shaft with Rotar	By Hand	Easy
11	Attached 1/4 in Metal Plate to Armature Shaft with Rotar	By Hand	Easy
12	Attached Metal Gear to 1/4 in Plate	By Hand	Easy
13	Attached Black Motor Connecting Wire to Armature	By Hand	Easy
14	Attached Red Motor Connecting Wire to Armature	By Hand	Easy
15	Attached Motor Screw to Casing	Phillips-head Screwdriver	Easy
16	Attached Spring Loaded Graphite Internals	By Hand	Easy
17	Attached Black Motor Connecting Wire to Spring Loaded Graphite	By Hand	Easy
18	Attached Red Motor Connecting Wire to Spring Loaded Graphite	By Hand	Easy
19	Attached 2 Cord Clamp Screws through the Cord Clamp to the Casing	Phillips-head Screwdriver	Easy
20	Attached Switch Breaker to the Trigger Switch	By Hand	Easy
21	Attached Plastic Lock Washers to the Lock on Button	Flat-head Screwdriver	Moderately Difficult
22	Attached Lock Spring to the Lock on Button	Flat-head Screwdriver	Easy
23	Attached Lock on Button to the Trgger Switch	By Hand	Easy
24	Attached Trigger Switch to the Casing	By Hand	Easy
25	Attached Shoe Plate Locking Knob to the Casing	By Hand	Easy
26	Attached Shoe Plate Locking Gear to Casing	By Hand	Easy
27	Attached Gel Max Comfort Grip to Casing	By Hand	Easy
28	Attached Casing to Casing	By Hand	Easy
29	Attached Plastic Blade Guard to Casing	By Hand	Difficult
30	Removed Rip Fence to Casing	By Hand	Easy
31	Attached Dust Blower and Rip Fence to Casing	By Hand	Easy
32	Attached Dust Blower Angle to Dust Blower	By Hand	Easy
33	Attached Rip Fence Bolt to Saw Blade Locking Lever	By Hand	Easy
34	Attached 7 Phillips-head Screws	Phillips-head Screwdriver	Easy, 1 Screw Quite Difficult

Post-Assembly

Assembly Review

- Assembly was just as easy as the disassembly with the exception of the trigger component. The trigger's spring loaded technology made it difficult to assemble, and a few parts were lost.

- Jig Saw does not work now due to lost parts within the trigger.

- AC power is brought in through the electrical cord to the trigger

- when the trigger is pressed the power is converted to DC power which goes to the motor

- the motor converts the DC power to rotational mechanical energy

- the motor connects to a gear that converts the rotational mechanical energy to linear energy on the blade holder

- the linear energy is used to cut materials when the blade is inserted

Analysis Tests

- Impact and Shock Test

- Test individual parts for durability, wear, and tear

Design Changes

THIS IS MIKE FAMA's PART!!!

Recommendations to Company

- Set variables speeds for different hardnesses of materials

- Stronger blade holder on the side

- Less grease on the gears, this would save Black and Decker money

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