WorksheetsDENT1014: The 17 Laws of Casting
Total questions: 15
Worksheet time: 8mins
The pattern sprue former should always be attached to the thinnest cross section of the wax pattern.
a) True
b) False
Alloy should flow from areas of greater volume to areas of lesser volume (ie.margins)
a) True
b) False
If the wax patterns are not positioned in cold zone, what penalty could occur?
a) short margins
b) cold shuts
c) incomplete castings
d) porosity
In order to compensate for metal/alloy shrinkage that occurs during solidification...
a) reservoir must have sufficient molten alloy
b) reservoir must have less molten metal
c) reservoir must have no molten metal
d) none of the above
A button must not be casted when using a runner bar.
a) True
b) False
When casting, turbulence must be avoided at all times.
a) True
b) False
To prevent bubbles from being trapped between investment and patterns a wetting agent (ie.picosilk) is used to decrease surface tension and increase wettability of pattern.
a) True
b) False
The water and investment liquid measurement for high noble/noble alloy (precious metal) is...
a) 11.5mL investment liquid/ 11.5mL water
b) 11mL investment liquid/ 12mL of water
c) 16mL investment liquid/ 7mL of water
d) 15mL investment liquid/ 8mL water
A bowl and spatula should be used to mix investment in order to avoid bubbles.
a) True
b) False
Investment should be allowed to set completely before placing in the burnout oven. Be sure to bench set your ring for...
a) 15 mins
c) 25 mins
c) 30 mins
d) 45 mins
The final burnout temperature depends on the metal being casted. **(good exam question)**
a) True
b) False
c) I don't know
During casting, the oxidizing zone of the flame should be used to melt the alloy.
a) True
b) False
The higher the density of metal, the lower centrifugal force is needed to cast --> the lower the density of metal, the higher centrifugal forces needed to cast.
a) True
b) False
During casting, metal will flow downward and to the right first. **(good exam question)**
a) True
b) False
After casting is complete, the casting ring can be quenched in water immediately.
a) True
b) False
