Thursday, 12 June 2014

Current Affairs

Another item on or wish list has been relocating the batteries and simplifying the cable routing. Previously, one battery was stored under the cockpit floor, while another battery (and the battery switch!) were in the starboard cockpit locker. Opening a locker lid at sea just to switch batteries seems less than ideal, and the inaccessible space under the cockpit looked ideal for the two batteries.

Supporting (nearly) rectangular batteries in the non-euclidian space of the boat's bowels is a different matter. No two sides or angles are ever the same, and only repeated test-fits and adjustments of the four legs and two sides produced the desired result. The front and back of the box each consist of two vertical and one horizontal batten, and a plywood wall, all epoxied and screwed together.

The flat surfaces were glued with liquid epoxy, the slightly less flat joints filled with a microfibres-thickened epoxy putty.

I glued the aft wall to the hull and cockpit floor first. The hull was prepared by sanding a pad around each leg back to fibreglass, and the legs were bedded in epoxy putty., supported by G-clamps.

Than, I cut the floor to the correct length, with overhangs left and right, and used it to locate the correct position for the forward wall. With Giulia's help, we repeated the above step for the latter.

Finally, a cross-brace was glued in, the floors fitted, equipped with cutouts for the tie-down straps, and coated in polyester, while the box legs were reinforced with patches of biaxial glass, and the whole structure coated with epoxy.

Each battery was lowered into a plastic tray, slid into the box, and the tray lid...
Well, the tray lid (red) just wouldn't fit - while a carefully measured the height to allow the lid to be inserted between the top of tray (white) and the underside of the cockpit floor, I forgot to account for the fact that battery terminals protrude above the tray.

Luckily, with the batteries now closer to the engine and the battery switch (which is now positioned above the chart table), the leads had enough slack to connect the terminals and close the lid with the battery slid out and tilted, before sliding the whole lot into the box.
The clash of the immovable with the incompressible has been averted, but maybe building a (screwed) full-scale mock-up before epoxying everything is not a bad idea after all.

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