PLTW Engineering​
Computer Integrated Manufacturing
Activity 2.1.2 Mass Properties Analysis Worksheet
Procedure
3.​ Answer the following questions using model 1.
Model
Properties
Model Material:
•​ Mild Steel (Steel, Mild)
Material Properties
•​ Density: 7.850
•​ Mass: 5.125
•​ Volume: 18.059
•​ Surface Area: 52.081
Model 1 – Slotted Angle Block
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a.​ What is the material cost of the part assuming that the cuttings are remelted and the cost of mild
steel is $6.25 per pound? What is the material cost of the part assuming that the cuttings are not
remelted?
5.128 * 6.25 = 32.05
7.004 * 6.25 = 43.78
b.​ What is the mass of the material lost in a typical machining process?
7.004 - 5.128 = 1.876
c.​ What is the cost of the lost material based on your calculations above?
1.876 * 1.25
d.​ What will the volume of the box (in cubic feet) need to be in order to ship 1000 parts packed
without spacers?
24.664 * 0.0005787 = 0.01427 = 14.3ft^3
e.​ What other processes could be used to create the same part?
One rectangle prism and mirror two trapezoidal prism
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Model
Properties
Model Material:
Stainless Steel
Material Properties
Density: 7.99g/cm^3
Mass: 3.612 lb
Volume: 12.499 in^3
Surface Area: 53.665 in^2
Model 2 – Mounting Bracket
4.​ Answer the following questions using model 2
a.​ What is the mass of the material lost in a typical machining process?
5 * 3 * 1.5 = 22.5
22.5 * 0.289= 6.503 lb
6.503 lb - 3.612lb = 2.891 lb
b.​ What is the cost of the lost material based on your calculations above if the cost of stainless steel
is $15.75 per pound?
2.891 * 15.75 = 45.33
c.​ What is the material cost of the part assuming that the cuttings are remelted? What is the material
cost of the part assuming that the cuttings are not remelted?
3.612* 15.75 = 56.89
6.503 * 15.75 = 102.42
d.​ What is the cost to ship 1000 parts if current shipping costs are $3.75 per pound?
3.612* 1000 * 3.75 = 13,545.00
e.​ What other processes could be used to create the same part?
combining two trapezoids on two layers of rectangle
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PLTW Engineering​
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Model
Properties
Model Material:
Aluminum 6061
Material Properties
Density: 2.710g/cm^3
Mass: 3.357lb
Volume: 34.291 in^3
Surface Area: 166.89 in^2
Model 3 – Support Bracket
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PLTW Engineering​
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5.​ Answer the following questions using model 3.
a.​ What is the material cost of the part assuming that the cuttings are remelted and the cost of
aluminum 6061 is $0.62 per pound? What is the material cost of the part assuming that the
cuttings are not remelted?
3.357 * 0.62 = 2.08
9 * 5 * 4 = 180
180 in^3 = 17.64 lb
17.64 * 0.62 = $10.937
b.​ What is the mass of the material lost in a typical machining process?
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PLTW Engineering​
Computer Integrated Manufacturing
17.64 - 3.357 = 14.283 lb
c.​ What is the cost of the lost material based on your calculations above?
14.283* 0.62 =$ 8.86
d.​ How many parts can be painted with one gallon of paint that covers 400 ft2?
166.89 = 1.1589/400 = 0.003 = 345 parts
e.​ What other processes could be used to create the same part?
create multiple rectangular prisms and chamfer them
Model
Properties
Model Material:
Soft Yellow Brass (Brass,
Soft, Yellow)
Material Properties
Density:8.47g/cm^3
Mass: 1.395kg
Volume: 164.650mm^3
Surface Area: 29.882m^2
Model 4 –Pipe Support
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6.​ Answer the following questions using model 4.
a.​ What is the material cost of the part assuming that the cuttings are remelted and the cost of soft
yellow brass is $13.50 per pound? What is the material cost of the part assuming that the cuttings
are not remelted?
1.395kg = 3.075445 lb * 13.5/lb = 41.52
2.754kg = 6.072 (13.5) = 81.97
b.​ What is the mass of the material lost in a typical machining process?
2.754 - 1.395 = 1.359 kg
c.​ What is the cost of the lost material based on your calculations above?
1.358 kg = 2.996* 13.5 = $40.45
d.​ What other processes could be used to create the same part?
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PLTW Engineering​
Computer Integrated Manufacturing
creating half of the model and then replicating it
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