Tile Flexane 80 putty is a room-temperature curing urethane, made up of flexane resin and 

 a curing agent that must be mixed together. After mixing, it has a pot life of about 15 

 minutes and once the two ingredients are mixed together, the mixture thickens and 

 further mixing is extremely difficult. 



The manufacturer advised the investigators that new belts were more difficult to bond 

 than used ones and that proper belt preparation was critical. The compound was applied 

 using the following technique: 



1- The area to which the Flexane putty was to be applied was roughened by a 

 wire wheel attached to a bench grinder. 



2- Using a paper towel and special cleaner provided in the kit, the area was 

 scrubbed clean. Then an abrasive pad (3M Scotchbrite pad) saturated with 

 cleaner was used to scrub the area. 



3- Area was then washed again with a paper towel saturated with cleaner and 

 this was repeated until no black transferred to the paper towel. Then let the 

 belts dry. This portion was very lor^ and tedious. Approximately four hours 

 were spent cleaning the surfaces. 



4- While the belts were drying the special mold boxes that the investigators had 

 fabricated for this part of the operation were set up and the mold release 

 agent applied to all inside surfaces. 



5- While step 4 was being performed, the rubber primer that was supplied with 

 the kit was applied to all surfaces to be t>onded. Once this primer is applied, 

 the Flexane putty should be applied within 10 to 60 minutes to insure full 

 bond strength. 



6- The Flexane was mixed and poured into the molds to form a half -inch thick 

 layer between the rubber being bonded, to form the section shown in Figure 

 2. 



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