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 Composite Chain plates

The chain plates on this boat are incorporated into a bulkhead that is tilted toward the mast at the angle of the shroud. This puts the tension in line with the working parts. I think this is a good way to go so haven't changed anything except (a big exception perhaps) the construction of the bulkhead itself. I used the method that was used in the fabrication of the main beam which is described in step 14 so I won't duplicate that part of the report here.

   I always made templates of cheap bracing ply of the bulkheads before committing to marine ply. A way to check for errors in the plans and so easy to loft the real stuff from tracing around them.
   This is the fabricated and laminated bulkhead with the positions cut out for installation of the uni e-glass which will be looped between the top of the stainless tube at lower left and the slot cut into the ply above it. It seemed to me that the easiest way to do this was to hang it upside down from the verandah. That puts it at hand level and the resin won't dribble down the face of it. I have removed the peel ply in the area of work.
   An error I made was in not removing enough ply under the stainless tube that will act as a bushing for the rigging. After the work is done there will be two slots cut into the top to allow room for the clevis for mounting the rigging screw. So the ply needs to be removed so when the cut is made only epoxy is exposed and not the timber. Otherwise the timber will eventually rot. After the bulkheads were mounted I got at it with a drill and narrow chisel and extracted the ply and backfilled with glue mix. It went so easy I would do it that way again.
   1000 gram by 100mm (4") unidirectional glass and a layer of 400 grm DB in the middle and at the end. I used 50% more than the plans called for and the plans were probably in excess. So I added about 2 kilos to the boat..
   A little glue mix to make sure the glass doesn't get air under it on the corners.
   First batch of resin, wet the table first and then...
   move the glass over and go....
   The whole length of the uni has to be dragged through the little hole every loop.
   Until it's all in there. The 400 grm DB cover is what is most of the overage. The sides were trimmed to the 100mm width called for and bogg was later used to fair and fill the sides.
   And mount em up! Check fit to the hull and I measured diagonally from each chain plate to the mast step to make sure they were square and equal.

 Steve from the cat Rosalie sailed in for a visit and gave a hand, welcome help!

These bulkheads have a heavier than average taping schedule. I used 6 layers of 750 tri-ax on the shear panel, decreasing to just the normal two layers by the inboard side. There is also a 300mm X 800mm piece of ply used as a doubling plate between the bulkhead and the deck, surrounding the upper end of the actual chain plate.