30.500-in.-long arm 

 with dial indicator 



Measurements were taken along the same 

 meridian as on the mold. 

 The deviations shown are with respect to an 

 arc described by a 30.500-in. radius indexed 

 with respect to the reference datum on con- 

 cave surface. 

 I I I I I 



10 



10 



5 5 



Lateral Radius (inches) 

 Figure 30a. Typical deviations from nominal 33-inch radius of curvature on 

 thermoformed sector 18 for the 66-inch-diameter capsule. 



hickness Before 



Thickness After 



Forming (in.) 



Forming (in.) 



2.390 



2.362 



2.467 



2.556 



2.502 



2.592 



2.477 



2.593 



2.404 



2.477 



2.430 



2.410 



2.432 



2.425 



2.425 



2.404 



2.430 



2.420 



Note: The increase in thickness is caused by lateral 

 shrinking of previously "unshrunk" grade G 

 Plexiglas plate after it was subjected to 300 F 

 forming temperature. The thinning out of the 

 formed sector at the center is due to stretching 

 of acrylic as the previously flat plate is forced 

 to conform to the spherical surface of the mold. 



Figure 30b. Effect of thermoforming on thickness of sector 18 for the 

 66-inch-diameter capsule. 



57 



