TD> replacing the plate sanwiched between the mast 
 TD> compression post and the keel on a 47 foot Vagabond 
 TD> For instance does the mast have to be removed or can 
 TD> the stays be loosened and jacks and props be used to 
 TD> support the mast while the compression post is removed 
 TD> to enable replacement of the plate to take place
Without the tension of rigging, clearly the deck has to be strong enough to 
support the dead weight of the mast or the deck couldn't handle normal people 
and other objects.  Any extra support under a mast is purely to handle static 
tension and running loads.  
Objects like mid height broadcast towers are sometimes jacked to change 
hardware at their bases without taking down the towers.  A mast is tiny by 
comparison, but also easy to sling into a crane as a simpler option to a 
temporary offset step, if a small boom truck is available.  
Terry
--- Maximus 2.01wb
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