Appendix F 



FABRICATION OF OPERATIONAL 

 66-INCH-OD x 61-INCH-ID ACRYLIC CAPSULES 



INTRODUCTION 



The knowledge and experience gained in developing the prototype 

 66-inch acrylic capsule (NEMO capsule 0) was immediately applied to the 

 production of three additional 66-inch capsules. NEMO capsule 1 was to 

 be mated with the THS (Transparent Hull Submersible) system by the 

 Naval Underwater Research and Development Center; NEMO capsule 2 was 

 to be incorporated into the NEMO system by the Naval Civil Engineering 

 Laboratory; while NEMO capsule 3 was to be utilized for further structural 

 tests. 



The three additional acrylic capsules were fabricated on contract by 

 Swedlow Inc. of Los Angeles, California. The reasons for contracting the 

 fabrication of the additional acrylic capsules to an industrial company were: 

 (1) to find out how well the fabrication techniques developed in a model 

 shop environment perform in an industrial shop environment and (2) to 

 develop in the plastics industry capability for mass production of NEMO 

 acrylic capsules. The metal polar plates for the capsules were again manu- 

 factured by the shop personnel of the Navy Pacific Missile Range. 



DESIGN 



The three acrylic capsules were fabricated according to the same 

 design used previously in the prototype 66-inch capsule. The only difference 

 in the specification was that instead of specifying only PS-1 8 adhesive for the 

 joints, other adhesives could be substituted for it providing their tensile 

 strength was in excess of 4,000 psi and the adhesive was as immune to sea- 

 water as PS-1 8 adhesive. 



The metal polar plates were also fabricated to the same basic design 

 as the prototype. Major differences were only the elimination of the plane- 

 tary gear hatch locking mechanism and the substitution of cadium-plated 

 type 4130 steel for type 316 stainless steel. Both changes were made for 

 economy. 



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