Service Bulletin: SB 074.1
Subject: Bottom Clamp Ring Mounting
On occasion it has been reported that the G-1000 Bottom Finishing Housing 19960-C failed in service due to operating loads on the stop ears. To eliminate this problem, a steel fabricated housing wag introduced on G-1000-XXXX-3700 series of machines as part number 25779-C. The use of a steel body rather then-cast materials eliminated the problem and all future machines and replacement-housings are of this new design.
With the change to steel, the tapped holes in the face of the housing used to secure the tooling clamp ring were changed to National Fine (1/4-28 NF) threads from the National Course (1/4-20NC) series.
Customers having both types of housings should take care to mark the different style housings and inform their operators of the difference so as to avoid using the wrong series of screws and possible stripping the threads.