Triumph TR6 Water Curtains
Omitting water curtains from a TR6 door when it is rebuilt will invariably mean rain water entering the door will soak the casing board and window regulator mechanism. This causes distortion or rotting of the casing board and rusting of the mechanism. The casing board can be protected by covering the access holes in the inner door frame with a heavy grade waterproof adhesive tape (a.k.a. 'tank tape' or 'gaffer tape') - the method now used by many modern car manufacturers.
Triumph originally listed a change point of CR1 and CF1 for the fitment of the above part numbered water curtains. The change of part numbers was not because of a change in design but due to an alteration of the material specification. In line with safety requirements and company policy, fire retardant or non flammable trim materials were specified and utilised where possible in the manufacture of Triumph cars.