to assembly varied from 2.285 to 2.585 inches and 30.702 to 30.345 inches, 

 respectively, while the external sphericity and the diameter of the assembled 

 capsule varied from 33.134 to 33.000 inches and 66.158 to 65.920 inches, 

 respectively. The difference between sphericity measurements taken on indi- 

 vidual pentagons and on the finished hull are attributed in a large measure to 

 (1) mismatch between individual pentagons during assembly, (2) excessive 

 polishing and buffing of the joint surface areas, and (3) difference in measuring 

 techniques (in one case dial indicator measurement of internal radius while in 

 the other case template measurement of the external radius). 



Figure 56. Measuring the diametral deviations of the bonded 66-inch capsule 

 with a 66-inch-throat micrometer. 



The magnitudes of sphericity, thickness, and diametral deviations from 

 specified nominal values when related to the size of the large-scale capsule show 

 that these deviations are approximately of the same magnitude as those mea- 

 sured on model capsules. While the relative sphericity deviation from the 

 specified internal radius on scale models was within +0.09 and -0.4%, on the 

 large-scale acrylic plastic hull it was within +0.50 and -0.66%. The relative 

 diametral deviation from nominal diameter for scale models was within +0.26 

 and -0.03%, while the large-scale hull's diametral deviations were within +0.25 

 and -0.12%. Since the comparison of relative dimensional deviations has 



85 



