A bell frame problem

[RONALD EAST]

 May I invite any members of the bell historians group to comment on this description of a ring of bells and on possible courses of action that might be taken? I would appreciate comments on the work itself and not on the involvement of architects, engineers, DAC advisors etc; I am interested in the feasibility of the project in practical terms at this stage.
   
  The frame is made of oak and is in good condition for its age with no indication of worm or fungal attack. The tower is dry and the fabric appears to be in good condition. The frame is of a traditional design and is braced with tie rods and cast iron plates at the major joints. The tie rods are rusted but are perfectly tight. There is some flexing of the timbers when the bells are rung but close inspection shows that the frame is rigid and there is no movement within the joints of the frame.
   
  The bell frame is built upon four wooden grillage beams that are bolted at their ends at right angles to two support wooden beams which rest on corbels built into E and W walls of the tower. These two beams rest against the walls and are not let into the fabric of the tower. A single bolt passes through each end of each of the four grillage timbers and so through the support beam below. A third support beam resting on corbels at its N and S ends braces the grillage timbers at the middle of the bell frame. 
   
  All three beams are visible in the ringing room and are of sufficient dimension the support the weight of the bells and bell frame. 
   
  The bells are all mounted in an E-W direction in the bell frame which means that at certain stages of ringing they all swing in the same direction.  The accumulated stresses cause an E-W movement in the frame of as much as 4mm relative to the masonry of the tower. The movement is apparent as a rocking of the support timbers on the E and W walls. The ceiling is also attached to the underside of the grillage timbers which gives an unnerving sense of movement of the belfry to the ringers below! 
   
  It would appear that the bolts passing through the grillage beams and the support beams below are not tight enough. They are rusted and probably cannot be further tightened. 
   
  A possible course of action is:
  1. Replace each rusted bolt by one or more stainless steel bolts tightened to a more appropriate torque, and
  2. brace the E and W support beams against the masonry, perhaps by injecting polyester resin.
   
  Ron East
   
           
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