[Public-List] Mast Beam Repair

[crufone at comcast.net]

Bill and Rachel, 

Thanks for your comments. The laminates are in sheer and this is what caused the original (Resorcinol?) glue to fail over time. 

Rachel, as the beam is compressed from above center on the arc it wishes to extend outward a thwratships.  This places the glue between the laminates under sheer stress. When the glue fails it allows the a thwartships movement which inturn allows the beam to 'flatten' in the middle ( from the top downward)and the rig to lo se tension. 

I would like to mention that I have no disrespect for the aluminum plate sistering fix for this application. To me, the wooden beam is part of the character and interior woodwork/furniture of the early boats which have them in place.  For a production boat to have this component last some forty years speaks well enough of it's original engineering. The adhesive has failed not the calculated load bearing requirements of the wooden components.  I am not attempting to reinvent the mouse trap as some others have suggested in the past.  My intent is to restore the original strength the beam was designed to have without changing it's appearance. 

Bill you seem to have much experience in the laying up of laminates. I thank you for coming forward to make suggestions. I hope that I can concact you for further advice when I am at the point of doing the lay up of my mast beam.  A couple of other owners who have early boats with wooden beams feel as I do about the appearance factor and are waiting in the wings to see how successful/durable my relamination repair is before they attempt their own repair. 

Thank you, 

Michael #133
 1262880231.0