1. November 12
2009
Project
08
Michael Tasevski
#34673430
MAE 377

2. Contents
1 Introduction..............................................................................................................................................4
1.1 Problem Definition / Problem Statement..........................................................................................4
1.2 Product Description...........................................................................................................................4
1.3 Design Goals......................................................................................................................................5
2 Research on Existing Products..................................................................................................................5
2.1 Survey on Existing Similar Products...................................................................................................6
2.1.1 Competitor #1: SKIL Detail Sander Model # 7300-01.................................................................6
2.1.2 Competitor #2: Porter-Cable Cordless 18V Detail Sander..........................................................6
2.1.3 Competitor #3: Black & Decker Cyclone Detail Sander...............................................................7
2.2 Product Comparison..........................................................................................................................8
2.3 Research Conclusion..........................................................................................................................9
3 Project Management..............................................................................................................................10
3.1 Project Gantt Chart/Time line..........................................................................................................10
3.2 Alternative Designs & Pros vs. Cons.................................................................................................11
3.3 Decision Making Table with Explanation.........................................................................................14
4 3D CAD Models.......................................................................................................................................15
4.1 3D Parts...........................................................................................................................................16
4.2 Sub Assemblies ...............................................................................................................................30
4.2.1 Electrical Motor Assembly........................................................................................................31
4.2.2 Switch Assembly.......................................................................................................................32
4.2.3 Drive Spindle Assembly.............................................................................................................33
4.3 Final Assembly.................................................................................................................................35
4.4 Final Rendering................................................................................................................................37
4.5 Animation........................................................................................................................................40
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3. 5 Manufacturing Analysis..........................................................................................................................41
5.1 2D Part Drawings.............................................................................................................................41
5.2 BOM Drawings.................................................................................................................................50
5.3 Cost Analysis/ Estimation.................................................................................................................54
6 Service Analysis.......................................................................................................................................54
6.1 User Manuel....................................................................................................................................54
6.2 Product Life Cycle............................................................................................................................55
7 Conclusion/Discussion............................................................................................................................55
8 References..............................................................................................................................................55
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4. 1 Introduction
Project 08 requires the design of a product of my choice. The product that I choose was a detail sander.
The content of this report documents the entire design process from design goals to final presentation
materials. The end result is a detail sander that is ergonomic, includes dust management, portable,
durable, and reasonably priced.
1.1 Problem Definition / Problem Statement
The final project requires the design of a new product that will compete with existing competitors’
products. Corner Sanders have been a very important carpentry tool for years. The available sanders
come in different sizes, are either battery or electric cord powered and have different power levels. One
of the most significant differences between the sanders however is additional functionality. A majority
of sanders have basic features such as switches, and battery powered motors. These sanders do the job
but they are a problem for someone who will be using the product for long periods of time.
1.2 Product Description
A detail sander (also known as "Mouse" or "corner"
sander) is a hand-held sander that uses a small
vibrating head with a triangular piece of sandpaper
attached. It’s used for sanding corners and very tight
spaces. This type of sander is a low powered sander
used in the finishing work of craft and detailed wood
work. Detail sanders are a basic type of sanders which
includes components such as, a small electric motor
powered either by battery or a cord, on/off switch, and
a spindle with a counterweight (for vibration).
Figure 1: Example Detail Sander
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5. 1.3 Design Goals
For this project a multiple feature corner sander will be created so that the extra functions will create a
much better working experience for the user. Areas that will be taken into account while designing the
sander are:
• Ergonomics
o Sanding is usually a very long and tedious part of woodworking. If a consumer is to be using
this product for long periods of time it must be comfortable.
• Dust Removal
o Sanding in wood work produces a lot of dust. Dust management is important to keep the
work area clean and safe for the consumer.
• Portability
o Detail sanders are either battery powered or corded. Battery powered sanders allow the
consumer to use the sander in more places and positions.
• Durability
o Wood working is a tough job. Tools that are used need to be rugged to allow multiple uses.
The less moving parts the less chance for the sander to break.
One area that will not be as emphasized but will be addressed is price. This tool will be designed as a top
of the line product with the best functions for the most serious carpenters. That being said this product
may be more expensive than competitors but will still be in a reasonable price range for the amount of
functionality it offers. This product will be made to be retailed at major Hardware retailer like Lowe’s.
2 Research on Existing Products
Since the targeted retailer for my product is Lowe’s I decided to look into the competition that my
product will be facing in the store. By browsing the competition at the store I found three big name
brands that offer some of the functions that I am looking to include in my design.
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6. 2.1 Survey on Existing Similar Products
2.1.1 Competitor #1: SKIL Detail Sander Model # 7300-01
Features:
• Dust management – The SKIL sander has a
vacuum type dust management system
that uses the spinning power of the electric
motor.
• Electric cord power delivery – This sander
uses a 10 ft cord to power the electric
motor which causes the vibration. The
10 ft cord restricts the portability of the
sander. Figure 2: SKIL detail sander
• Plastic material is used for housing
• Priced at $49.97 which makes it one of the more expensive of the surveyed products
• “Mouse” type control and ergonomics with on/off switch located in front.
2.1.2 Competitor #2: Porter-Cable Cordless 18V Detail Sander
Features:
• Dust Management – This sander has a
vacuumed dust management feature, yet it
is not included with the main unit. It must
be purchased separately.
• Battery powered delivery – This sander
uses a 18 V rechargeable battery to power
the electrical motor making it very
portable.
NOTE: Battery and charger sold separately
• Plastic material is used for the housing Figure 3: Porter-Cable detail sander
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7. • Priced at $29.97 makes it the cheapest of the survey products but seeing that the
charger, battery, and vacuum attachment are not included this price and product is not
as reasonable as one might think.
• “Iron” type control and ergonomics with on/off switch on top
2.1.3 Competitor #3: Black & Decker Cyclone Detail Sander
Features:
• Dust Management – Uses Cyclone
technology (type of vacuum) to remove
dust from working area.
• Electric cord power delivery – This sander
uses a 6 ft. cord to power the electric
motor. The 6 ft cord restricts the portability
of the sander greatly.
• Plastic material used for housing
• Priced at $54.97 which makes it the most
expensive out of all the sanders surveyed Figure 4: Black & Decker detail sander
• “Mouse” type control and ergonomics with on/off switch on front of sander.
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8. 2.2 Product Comparison
The Table below shows the comparison of features from the competitors surveyed.
Competitor SKIL Porter-Cable Black & Decker
Picture
Dust
Management
YES YES YES
Battery
Powered
NO YES NO
Housing
Material
PLASTIC PLASTIC PLASTIC
Control Type
PALM IRON PALM
Price
$49.97 $29.97 (WITH ADDITIONAL $54.97
COSTS)
Figure 5: Shows the comparison of competitor’s products.
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9. 2.3 Research Conclusion
After researching my products competitors I realized that there is a need for improvement in detail
sanders. The sanders all addresses and lacked in certain areas of my design goals. All of the sanders
were reasonably priced and I intend to put my price point at $60.00 for my sander. All three sanders are
made of a stronger and rigid plastic. Although I would like to make my sander more durable by making
all parts out of a type of metal, it would be impossible for me to keep the price point that I have made.
Therefore I will have to follow suit and use the same plastic for my outer housing. All three sanders
have dust management and my design will have a Vacuum dust management system also. One area
that my Sander will excel is the portability capabilities. Two of the three sanders (Black & Decker/SKIL)
are powered through an electrical cord. This limits the portability of the sander to around 15 ft. from an
electrical outlet. My Sander much like the Porter-Cable Sander will be battery powered allowing easy of
movement around the project and no workplace restrictions. After researching all three sanders it
seems that they all lack in ergonomics. The SKIL sander is controlled by the palm which gives it good
ergonomics for the user, yet the on/off switch is placed in an inconvenient place that takes away from
the ease of use. The Porter cable lacks the most in ergonomics. It has an “iron” type control. This type
of control doesn’t give the user good control accuracy and is uncomfortable for long periods of time.
The Black & Decker sander much like the SKIL sander also has an inconvenient on/off switch placement
for the user. This issue with ergonomics gives my sander the ability to excel.
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10. 3 Project Management
Project management is the art of matching a project's goals, tasks, and resources to accomplish a goal as
needed. In project 08 I will need to use good time management to accomplish all the requirements for
the project.
3.1 Project Gantt Chart/Time line
Figure 6: Project Gantt Chart
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11. 3.2 Alternative Designs & Pros vs. Cons
From the previous survey I decided that the sander I will be designing will have features such as dust
removal, battery powered, and it will be made of plastic. The only major decision I have is to make the
Sander very ergonomic. All of the drafts of the designs below are only emphasized on the ergonomics
because basic features will all be the same.
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13. Design #1:
Design #1 has an iron shaped sanding area with a
computer mouse shaped grip and the on/off switch on
the side of housing to be used with the index finger
and thumb.
Pros: The mouse shape gives comfort to the hand while
using the sander.
Cons: The buttons are easy to reach but may become a
nuisance with long term use.
Figure 7: Design #1
Design #2:
Design #2 has an iron shaped sanding area with a round
shaped grip and the on/off switch on the side of housing
to be used with the index finger and thumb.
Pros: The round shape allows multidirectional placement
to the hand while in use.
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14. Cons: The buttons are easy to reach but may become a nuisance with long term use.
Figure 8: Design #2
Design #3:
Design #3 has an iron shaped sanding area with a mouse
shaped grip and the on/off switches on the top of the
sander much like a computer mouse.
Pros: The mouse shape allows good comfort to the hand
while in use, and the buttons are well placed and allow the
best precision.
Figure 9: Design
3.3 Decision Making Table with Explanation
Design #1 #2 #3
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15. Picture
Dust
Management
9 9 9
Portability
10 10 10
Price
8 8 9
Ergonomics
6 6 10
Total
33 33 38
Figure 10: Shows the comparison table of the Design Option
4 3D CAD Models
On completing the sketches I was able to create 3D models of all the parts and combine them into an
assembly to get my final product by using Pro/E. This part of the project required a lot of time but the
end result is an exceptionally great detail sander.
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16. 4.1 3D Parts
The following figures are all the parts of the detail sander created in Pro/E
Figure 11:
Figure 11 shows views of the Base. The bottom of the base is made of Velcro to allow quick change of
sandpaper. It also has holes to allow dust to pass through into the vacuum assembly.
(a) (b)
Figure 11(a) The CAD model of the base; and (b) the same CAD model at a different view.
Figure 12:
Figure 12 shows views of the Main housing. The Main housing was the hardest part to create and model.
The main housing is the exoskeleton of the assembly where each part needed to be form fitted to insure
proper function. The Main housing was created using methods such as extrude, hole, blend, round, and
mirror. This is only one of the sides of the main housing. To get two sides I first modeled the entire
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17. housing together while adding all the features and at the end I cut the part in half and saved the two
sides.
(a) (b)
(c ) (d)
Figure 12(a) The CAD model of the Main housing; and (b)(c)&(d) the same CAD model at different views.
Figure 13:
Figure 13 shows views of the battery.
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18. (a) (b)
Figure 13(a) The CAD model of the battery; and (b) the same CAD model at a different view.
Figure 14:
Figure 14 shows views of the Vacuum Bag. The vacuum bag was a tougher part to make due to the
warps placed on the body to give the “fabric” effect. While creating this part you had to be very careful
of where the warps were created. If the warp affected the shape of the black lip the bag would not be
able to be constrained to the housing during assembly.
(a) (b)
Figure 14(a) The CAD model of the vacuum bag; and (b) the same CAD model at a different view.
Figure 15:
Figure 15 shows views of the battery clip. This part is used to hold the battery into the sander.
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19. (a) (b)
Figure 15(a) The CAD model of the battery clip; and (b) the same CAD model at a different view.
Figure 16:
Figure 16 shows views of the battery clip pin. This pin is used to hold the battery clip to the housing.
(a) (b)
Figure 16(a) The CAD model of the battery clip pin; and (b) the same CAD model at a different view.
Figure 17:
Figure 17 shows views of the bearing ball.
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20. (a) (b)
Figure 17(a) The CAD model of the bearing ball; and (b) the all the balls of a bearing together.
Figure 18:
Figure 18 shows views of the outer bearing casing. Holds the bearing balls
(a) (b)
Figure 18(a) The CAD model of the outer bearing casing; and (b) the same CAD model at a different view.
Figure 19:
Figure 19 shows views of the bearing cover. Use to keep debris and dirt away from the balls
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21. (a) (b)
Figure 19(a) The CAD model of the bearing cover; and (b) the same CAD model at a different view.
Figure 20:
Figure 20 shows views of the inner bearing casing. Holds the bearing balls.
(a) (b)
Figure 20(a) The CAD model of the inner bearing casing; and (b) the same CAD model at a different view.
Figure 21:
Figure 21 shows views of the bearing spindle. The spindle is basically a rod the bearings are press fitted
onto which allows the rod to spin. This spindle also holds the drive gear and vacuum fan.
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22. (a) (b)
Figure 21(a) The CAD model of the outer bearing casing; and (b) the same CAD model at a different view.
Figure 22:
Figure 22 shows views of the drive gear 1. The gear was created using the revolved cut feature and
chamfer for the teeth. The large amount of chamfers on this part had to be done a few times because
the program would freeze.
(a) (b)
Figure 22(a) The CAD model of the drive gear 1; and (b) the same CAD model at a different view.
Figure 23:
Figure 23 shows views of the vacuum fan. The vacuum fan is the most important part of the vacuum
system. It is press fitted onto the spindle and is spun at 10000 orbits per minute. The protruding blades
of the fan are what cause the vacuum for dust removal. Note that there is an added extrusion on the
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23. fan. This extrusion acts as a counter-weight. When spun at 10,000 opm’s it creates the circular vibration
for the sander.
(a) (b)
Figure 23(a) The CAD model of the vacuum fan; and (b) the same CAD model at a different view.
Figure 24:
Figure 24 shows views of the motor casing. All the components of the electric motor reside inside of the
motor casing.
(a) (b)
Figure 24(a) The CAD model of the motor casing; and (b) the same CAD model at a different view.
Figure 25:
Figure 25 shows views of the motor sleeve.
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24. (a) (b)
Figure 24(a) The CAD model of the motor sleeve; and (b) the same CAD model at a different view.
Figure 26:
Figure 26 shows views of the Armature axel. The Armature axel acts as an axis for the work done by the
electromagnetic force of the motor.
(a) (b)
Figure 26(a) The CAD model of the Armature axel; and (b) the same CAD model at a different view.
Figure 27:
Figure 27 shows views of the commutator. The commutator is a coil of copper which allows current to
flow and cause the spinning movement caused by electromagnetic.
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25. (a) (b)
Figure 27(a) The CAD model of the commutator; and (b) the same CAD model at a different view.
Figure 28:
Figure 28 shows views of the field magnets. The field magnets are what produce the poled magnetic
field that the motor uses to run.
(a) (b)
Figure 28(a) The CAD model of the field magnets; and (b) the same CAD model at a different view.
Figure 29:
Figure 29 shows views of the motor cap. The motor cap covers the inner motor components and has
the electrical wire contacts.
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26. (a) (b)
Figure 29(a) The CAD model of the commutator; and (b) the same CAD model at a different view.
Figure 29:
Figure 29 shows views of the motor fan. The motor fan is attached to the armature axel and helps cool
the motor down with the help of vents.
(a) (b)
Figure 29(a) The CAD model of the motor fan; and (b) the same CAD model at a different view.
Figure 30:
Figure 30 shows views of the mouse top. The mouse top gives the ergonomic feel of a computer mouse
with similar position of the buttons.
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27. (a) (b)
Figure 30(a) The CAD model of the mouse top; and (b) the same CAD model at a different view.
Figure 31:
Figure 31 shows views of the left mouse button. The left button is made of a plastic that allows it to
bend at the tab enough to move the switch.
(a) (b)
Figure 31(a) The CAD model of the left button; and (b) the same CAD model at a different view.
Figure 32:
Figure 32 shows views of the right mouse button. The right button is made of a plastic that allows it to
bend at the tab enough to move the switch.
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28. (a) (b)
Figure 32(a) The CAD model of the right; and (b) the same CAD model at a different view.
Figure 33:
Figure 33 shows views of the switch. Notice the copper insert. It allows the change in contact to turn
the sander on and off.
(a) (b)
Figure 33(a) The CAD model of the switch; and (b) the same CAD model at a different view.
Figure 34:
Figure 34 shows views of the switch housing.
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29. (a) (b)
Figure 34(a) The CAD model of the switch housing; and (b) the same CAD model at a different view.
Figure 35:
Figure 35 shows views of the switch pin. It holds the switch into the housing and allows it to pivot.
(a) (b)
Figure 35(a) The CAD model of the switch pin; and (b) the same CAD model at a different view.
Figure 36:
Figure 36 shows views of the 3 electrical wires. The red wires are the “hot” ones and the black wire is
the ground. The wires were difficult to create because of the 3D paths they needed to be swept at.
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30. (a) (b) (c)
Figure 36(a) (b)&(c) show CAD models of the three wires.
Figure 37:
Figure 37 shows views of the 3 different sized screws and the head of the screws. The screws all had the
same .1 inch diameter and Philips
(a) (b) (c) (d)
Figure 37(a) (b)(c) show CAD models of the three screws and (d) shows the head of those screws
4.2 Sub Assemblies
The final assembly of the detail sander was not created at one time. Three sub assemblies of the electric
motor, the switch, and the drive spindle were all needed prior to the final assembly.
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31. 4.2.1 Electrical Motor Assembly
Figure 38:
Figure 38 shows views of the electric motor assembly. The 8 parts making up the assembly are the
armature, casing, sleeve, gear, field magnets, commutator, cap, and fan. The motor uses the electrical
power from the battery to create an electromagnet which then creates mechanical power by spinning
the gear. Some point to notice on the motor is the vents on the casing and cap work together with the
fan to vent the motor to avoid overheating. Another point to notice is the precision of the gears. The
teeth have to be the same size to insure proper function
(a) (b)
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32. (c ) (d)
Figure 38(a) The CAD model of the electric motor assembly; and (b)(c)&(d) the same CAD model at different views.
4.2.2 Switch Assembly
Figure 39:
Figure 39 shows views of the switch assembly. The 3 parts making up the assembly are the switch,
switch housing, and switch pin. The switch operates as toggle about the axis of the switch pin. Notice
when the switch is either neutral or OFF the copper contact only will be applied to one wire (Figure 39c).
When the switch is put in the ON position both wires will be contacted thus completing the circuit and
allowing the sander to run (Figure 39d).
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33. (a) (b)
(c ) (d)
Figure 39(a) The CAD model of the switch assembly; and (b)(c)&(d) the same CAD model at different views.
4.2.3 Drive Spindle Assembly
Figure 40:
Figure 40 shows views of the drive spindle assembly. The drive spindle is made up of 5 parts: The
spindle, drive gear, vacuum fan, and 2bearings. All the parts and press fitted onto the spindle. When
the motor gear engages the drive gear the entire assembly rotates easily with the help of the bearings.
The bearings are an entire assembly in themselves. The bearing assembly consists of 4 parts: The outer
and inner casing, bearing ball, and bearing cover. Good part precision was needed to create this
assembly to allow all the parts to fit and function correctly.
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34. (a) (b)
(c ) (d)
Figure 40(a) The CAD model of the drive spindle assembly; and (b)(c)&(d) the same CAD model at different views.
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35. 4.3 Final Assembly
Figure 41:
Figure 41 shows views of the Final assembly. The final assembly incorporated all the previous
sub-assemblies, and some misc. parts. These parts include, wires, screws, main housing, battery,
vacuum bag, mouse top, base, and buttons. Figures 41a shows the final assembly all together. Figure
41b shows the inner components of the assembly. Figures 41c & d show the exploded views of the
assembly, and Figures 41e & f show the components minus the housing, along with a close up of the
wiring.
Putting together the final assembly was very tough and tedious. Everything needed to fit just
right to function correctly. I also happened to lose my final assembly once due to a saving error in my
housing. A majority of the components were constrained to the housing and that is why I lost them too.
(a) (b)
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36. (c ) (d)
(e) (f)
Figure 41(a) The CAD model of the final assembly; and (b)(c),(d),(e)&(f) the same CAD model at different views.
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37. 4.4 Final Rendering
Figure 42: Rendering #1 of final assembly.
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38. Figure 43: Rendering #2 of final assembly.
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39. Figure 44: Rendering #3 of final assembly.
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40. 4.5 Animation
You can find the animations at sites.google.com/site/michaltasevskicaddesign.
Figure 44: A screen shot of an animation of the sander.
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41. 5 Manufacturing Analysis
5.1 2D Part Drawings
Figure 45: 2D drawing of the switch sub-assembly
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42. Figure 46: 2D drawing of the drive spindle sub-assembly
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43. Figure 47: 2D drawing of the motor sub-assembly
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44. Figure 48: 2D drawing of the bearing sub-assembly
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45. Figure 49: 2D drawing of the switch sub-assembly
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46. Figure 50: 2D drawing of the wires
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47. Figure 51: 2D drawing of the battery & clip
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48. Figure 52: 2D drawing of the top parts (rubber palm grip, and buttons)
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49. Figure 53: 2D drawing of the vac-bag and base
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50. Figure 54: 2D drawing of the housing
5.2 BOM Drawings
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51. Figure 55: 2D BOM drawing of the Final Assembly
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52. Figure 56: 2D BOM drawing of the Drive Spindle
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53. Figure 57: 2D BOM drawing of the Electric Motor
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54. 5.3 Cost Analysis/ Estimation
Price
Part Qty. Price (Total)
Electric Motor (18
V) 1 $5.00 $5.00
Wire/Contacts 3 $0.50 $1.50
Plastic Buttons 2 $0.50 $1.00
Rubber Grip 1 $1.00 $1.00
Screws 8 $0.06 $0.48
Toggle switch 1 $0.50 $0.50
Housing 2 $3.00 $6.00
1" Bearings 2 $2.00 $4.00
Pins 3 $0.05 $0.15
Spindle 1 $0.50 $0.50
Cast Vacuum Fan 1 $1.00 $1.00
18 V Battery 1 $10.00 $10.00
Gears 2 $0.75 $1.50
Base
(Plastic/Velcro) 1 $3.00 $3.00
Battery clips 2 $0.50 $1.00
Total: $36.63
Figure 58: Table of Cost Analysis made in excel
After performing a cost analysis by using a parts website and my knowledge from working at a hardware
store I found that my sander’s total cost would come to $36.63 to make. This $13.37 less than the price I
stated earlier in the repost. This allows my product to produce a profit and remain competitive.
6 Service Analysis
6.1 User Manuel
Please see attached document
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55. 6.2 Product Life Cycle
The Sandmaster 3000 will include everything needed to be used at the time of purchase. Not shown in
the report is Velcro backed sandpaper and a battery charger for the sander. The Sandmaster 3000 will
be a very durable product due to the minimal moving parts and rugged plastic housing. The Sandmaster
3000 will be backed by a 3 year warrantee which covers product failure, and parts will be available to
order if it break after this time. This sander is made for around 3 years of use but with carful use it can
last longer.
7 Conclusion/Discussion
Overall I believe that Project 08 was a Success. I was able to complete all requirements and ended with a
product that has the possibility to be in the market today. I covered all of the material learned in class
by doing this project and learned more in the process. As always time was an issue with this project and
I needed all of the time allowed. One major issue that I encountered was the lack of memory and space
the computers in the lab provided to do rendered animations. I had my animations crash numerous
times and it was very frustrating. That is why I decided to only do unrendered animations. If I had more
time with this project I would have enjoyed making my sander even more detailed and crating better
animations. Over all I have learned a great deal about the design process and PRO/E from this project.
8 References
http://en.wikipedia.org/wiki/Sander
http://www.lowes.com/lowes/lkn?action=productDetail&productId=237112-353-7300-01&lpage=none
http://www.lowes.com/lowes/lkn?action=productDetail&productId=159337-79992-
PC18DS&lpage=none
http://www.lowes.com/lowes/lkn?action=productDetail&productId=226118-79992-
MS1000%20%201&lpage=none
http://electronics.howstuffworks.com/motor4.htm
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