Tuesday, January 24, 2012

Mist is to Have a Foam Core Deck


The kids really are working under there, not resting. They're marking the frames and stringers so we know where to place glue and clamping screws.






 

I've performed a few tests to determine deck stiffness, toughness, and weight of various deck combinations.  I chose to compare 1/4" Okoume w/ one side laminated 10oz cloth, 3/8" Corecell a500 w/ topside 10oz underside 6oz, and 1/2" Corecell a500 w/ topside 10oz underside 6oz.  The 3/8" thick sandwich weighed half that of the 1/4" Okoume and was approx the same stiffness.  The 1/2" thick sandwich weighed 25% less then the 1/4" Okoume and was twice the stiffness.   As far as toughness is concerned, I dropped a 3 1/2# round weight for 3 foot high onto the samples.  The weight went right through the Okoume and bounced off the 1/2" foam core.  It took several drops of the weight to show a significant damage to the foam.   Cost and labor is significantly higher for the foam lay-up and installation and the areas where hardware mounts will need reinforcement.  I plan to use the 1/2" foam combination on the deck and the remaining sheet of 3/8" foam on the cabin top.


Monday, January 16, 2012

Keel Box Finished


Keel box is completed and the last portion of the bunk is installed.


I suppose the photo below is the last one to show the shiny interior.  Next project is the cockpit floor.


My daughters are getting a kick out of removing the peel-ply from the cockpit floor material (1/2" foam, 6 oz cloth on the underside and 10 oz cloth on the top side).  This panel is quite rigid!