Figure 44. Residual stresses not removed by annealing in a 15-inch-diameter 

 capsule with cast-in-place joints. 



This method of assembling and bonding the capsule possessed several 

 disadvantages not present in the method of assembly used on solvent-bonded 

 models, which permitted bonding of all 12 pentagons in one operation. These 

 disadvantages were (1) difficulty in checking the sphericity of the assembled 

 hemisphere prior to bonding, (2) distribution of dimensional mismatches 

 between individual pentagons over the surface of a hemisphere only, and 

 (3) inability to accomplish a perfect match between the irregular joint sur- 

 faces of the two mating hemispheres. But it was hoped that with proper 

 attention to the sphericity and diameter of each individual hemisphere, a 

 capsule could be assembled with small deviations from nominal diameter and 

 sphericity. 



74 



