Coring The Poop Deck & Sanding

August 26, 2017

As parts and materials arrived through the week; specifically, the new bronze outboard bracket from Rig Rite and an order of balsa core.  Saturday morning, I was eager to begin prepping to tackle laying new core down on the poop deck.  First, however, I wanted to get the sanding of the topsides finished: waterline and bow.  

As you can see below, I had the bow portion to finish.  The Porter Cable 7335 with dust shroud could not get underneath the stem fitting, and I was cautious about using it on the point of the bow.  I opted to use the RO palm sander for a bit more finesse and control.  

Using 80-grit discs, I made quick work of this section of the topsides.

The bulk of today's sanding time was eaten up by finishing the waterline.  This portion of the topsides, unfortunately, had to be done by hand....had to be done though.  I made a slow and methodical path around the boat, sanding the topsides paint and primer down to gelcoat while preserving the demarcation between the bottom paint and the topsides.  Later, I will tape of the waterline as I prepare for primer.

Satisfied that the topsides sanding was behind me, I was excited to turn my attention to addressing the coring work on the poop deck.  I started by giving the open deck areas a good vacuum and solvent wipe down.

Next, I applied a piece of heavy mil plastic over the deck, and using a Sharpie, traced patterns to be applied to the balsa.

I went ahead and labeled everything thoroughly, careful to preserve every square inch of the "prey-cious" balsa core.  But seriously, my thinking here is that I can utilize the balance of the material across other areas on the boat that are exhibiting 'deck-flex': one portion of the cockpit sole and the cabin sole. 

I cut out the pattern and transferred them to the balsa sheet.  With a box cutter, I pulled the patterns from the sheet of balsa and inserted them for a test fit.  Each of the four portions of balsa that I cut fit nicely on the first attempt, and any gaps between the old and new core would be filled with thickened epoxy.  I was ready for the next step.

Prior to laying the new core down, I wanted to prep the deck surface to received the new fiberglass 1708 biaxial cloth.  I used an angle grinder outfitted with a 40-grit flap wheel to create a tapered edge around each of the areas of the deck that i had opened up.  The tapered areas are roughly 2" in width.

I set up an epoxy work station at Joule's stern, and prepared materials to lay the new base core down: mixing cups, stir sticks, nitrile gloves, chip brushes, and thickening agents.

With the Florida August heat, exothermic epoxy reaction, and my penchant to not waste materials, I was not able to get a pictorial play-by-play of the lay-down.  The open working time during the summer months is limited, and as all parents eventually say, "use your words."  This is how it went down:  I wet out of the bottom skin on the poop deck with epoxy mixed "neat" (no thickening agents) , as well as the bottom of the new balsa core.  Next, I mixed epoxy thickened with microballoons and laid out a layer on the bottom skin, one area at a time.  I then pressed the balsa core into place, seeing sufficient squeeze-out of the thickened epoxy.  I cleaned up the excess squeeze-out, and then placed a sheet of plastic over the poop deck.  On top of the plastic, I placed some weights to keep the core in place and under the present poop deck concave surface.  I'm looking forward to seeing the results, and prepping to lay new glass down.   

Total Time Today: 6.25 hours