A message from the Chief Measurer:
The original specification for fitting RCB tracks stipulated that 4 x 1/4" MTS bolts be used. Recent discussions with the Designer have resulted in the following amendment and clarification.
Effective immediately, 1/4" MTS bolts must be used at the front and rear ends of RCB tracks. Other, intermediate bolts, of which there may be 1 or 2, may be either 3/16" or 1/4" MTS.