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Re: Centerboard optimization opportunity.

PostPosted: Sat Feb 24, 2018 2:17 am
by baggywrinkle
Here is start of modification to the Thistle CB. Making space for burying the SS plate which will spread the 70LB load that the foam and glass could not survive. The SS plate will also provide attachment point for lifting

The manila and blue tape item is the pattern, made to follow thick the section, and to leave plenty of the edges intact. The white piece on the left is the FG skin removed. The Black section is the Lead shot, tight in resin. The brown stuff is the adhesive (thickened resin). The light green stuff is the foam, which in this area is little scraps randomly placed in the resin. Why? My guess is that foam scraps are less expensive than resin. Also, the glass fabric on the inside surface of the white cut-out was dry, not resin saturated. Maybe it was a Monday morning or a Friday afternoon at the CB factory.

At this stage in the pic, the core is being removed, leaving one side of the FG skin intact. The SS will be buried in the middle with chopped glass and epoxy. I settled on 3/16 #316 SS plate. Holes will be drilled thru it for more resin gripping. To drill those holes quickly, I might take it to the firing range. Where the two holes will be, for CB pin and for lifting attachment, I thought I'd build it up with additional layers of the plate welded on. Maybe also add some SS threaded rod, lengthwise, overlapping the cut-out to help stiffen it as it has now lost its original skin on one side.


rsz_1cb_surgery_thistle_cb.jpg (199.57 KiB) Viewed 1305 times