hatch/deck core

I took the hatch and frame off my boat (#151) recently to investigate a small leak. I think the hatch frame was the culprit on my boat.  No wetness in the wood (it is pretty dry here in the Okanagan), but the wood had delaminated and the deck was soft on the forward and starboard sides and part of the port side.  Aft edge was solid.  Dug out wood to get back in about 3 inches to solid material, beig careful not to damage the thin fibreglass skins.  Machined clear cedar piece for the starboard side - it is straight - and cedar strips for the curved forward edge.  Epoxied them all in using West System Epoxy.  Roughed up the cedar with 80 grit paper and treated it with Xylene to strip out any natural oils near the surface. 

The cedar strips for the curved forward edge were thin enough to spring to the curved shape and sized so 3 thicknesses fitted nicely in the space.

Used clamps evey 2 inches to hold the whole thing together whilst the epoxy set up.

I obviously haven't tried a destruction test but it seems to be very strong now, no flexing whatsoever. 

I laminated ply /cloth/ply/cloth into the area.  I clamped it with a strip of plywood faced with medium density foam behind waxpaper.  The foam give uniform pressure without have to over tighten and squeeze out the epoxy.