segments of plate 52 block flow through the nozzles 29 to the waste area 31 consequently the plastisol gels less on the waste area while it builds up as a greater gel thickness on the finish areas of the mold fig6 illustrates the alignment of the plates 52 56 which permits hot or cold air to flow to all surfaces of the mold for 34 fusion 34 or 34 cooling 34 this is accomplished by moving plate 52 to the left a distance equal to one half the nozzle to nozzle centerline spacing since the 34 waste 34 area 31 as noted before will be at some lower temperature than the 34 finish 34 area because of not having been heated as long it can be brought up to the full 34 fusion 34 temperature by indexing plate 56 to the left as shown in fig7 this blocks air flow to the 34 finish 34 areas 24 28 and permits the 34 waste 34 area 31 to come up to temperature when 34 cooling 34 is called for plate 56 is shifted back to the right and all nozzles have access to the cold air the above valve action is predicated on valve movement corresponding to a nozzle to nozzle spacing of.