June 22, 2019
It has been on my mind lately that the pace of the project needs to increase just a bit...yes, we have just entered hurricane season and the boat is better off in the relative safety of north Florida, but my goal is to have the owner sailing his Allied 24 by the fall. With brightwork fabrication, paint, and the auxiliary installation being the remaining large items, I will be pushing the pedal a bit harder going forward.
There was this annoying little "creak" and "pop" whenever I stepped to the aft of the cockpit, and my numerous attempts to root out the cause of the sounds always came back with an unsatisfying result. My inclination was that the cockpit well itself was flexing around the rudder post...but delimitation of the core material was persistently trying to argue its case. I relented and prepared to open up the cockpit floor.
I marked the area of concern, ensuring that I provided ample room around the perimeter of the cut to taper the top skin in order to lay down new fiberglass and tie the new into the old.
Next, with the oscillating tool, I cut open the topspin and removed it, along with the old core. What I found was good adhesion of the balsa core to the top skin...but delimitation of the balsa core to the bottom skin. I believe I found the origins of the "creaks" and "pops"!
With the core removed and the cavity cleaned out, I traced around the opening for the purpose of grinding a taper to allow a smooth transition from new material to old material.
With the taper prepared in the work area, I thoroughly cleaned it by vacuuming and solvent-washing the surfaces.
During a trip back to the shop (a regular up-and-down-the-ladder experience), I grabbed some plastic sheeting in order to create templates for the new fiberglass cloth (1708 biaxial) and for the 1/2" balsa core.
Back in the shop, I prepared the new layers of fiberglass (3, in successively larger sizes), and the new core material.
I wet out the balsa core and the surfaces of the cockpit floor with neat epoxy - epoxy resin with no thickening agents. With the remaining resin in the cup, I thickened it with 406 colloidal silica. With the thickened epoxy, I troweled a bed of it down onto the surface of the bottom skin, and then pressed the new balsa core into place.
With the balsa core in place, I came back with another batch of thickened epoxy to spread across the surface of the new balsa core and to press into the small voids around the perimeter of the old and new core.
I hustled back to the shop to wet out the three layers of 1708 biaxial cloth that would form the new top skin. The "hustle" adjective is a gentlemanly way of saying..."I ran like my ass was on fire!" The Florida heat punishes those working outside, and those working outside with epoxy resin. I managed to get the layers wet out and back to the boat to lay down with time to spare, but I could certainly feel the heat coming off due to the exothermic reaction. I finished the work area with a layer of peel ply...this stuff is the best: no sanding, ready for fairing compound or additional layers of glass.
The last item on the list for the day was to complete the aft bulkhead core work. The aft bulkhead of the Allied 24 was simply 1/4" thick (if that) solid laminate. In my opinion, the bulkhead needed some "meat", or reinforcement; it also needed some width dimension to better fit out companionway trim. So to address those issues, I decided to add 3/8" thick balsa core to the entirety of the cabin's aft bulkhead. In a previous work session I applied balsa core to the starboard and port side of the cabin's aft bulkhead - to the starboard and port side of the companionway. I then applied a layer of 1708 biaxial cloth to the starboard and port side and faired the surface...the smallish middle section now required attention in order to complete the bulkhead.
As I had done for the aft cockpit floor, I made a template for the balsa core and single layer of 1708 biaxial cloth. In the shop, I trimmed a piece of 3/8" balsa core and also cut a layer of 1708 biaxial. Next, and after solvent-washing the surfaces, I wet out the small section of laminate at the companionway. With the remaining epoxy resin, I wet out the balsa core and the biaxial cloth.
I then mixed a pot of the thickened and spread it onto the surface of the companionway laminate - I used a squeegee that I custom altered to include notches like a trowel has. I pressed the new balsa core into position. The thickened epoxy grabbed hold of the balsa core and held it in its vertical position. With the remaining thickened epoxy, I created a rounded fillet between the bottom edge of the balsa core and the interior surface of the original laminate. This fillet would allow the single layer of 1708 biaxial to neatly lay over the balsa core and then wrap onto the original laminate material. As described, the application was completed and successful. I finished the work with a layer of peel ply material. In the next session, I will apply a coat fairing compound to the aft cockpit and aft cabin bulkhead surfaces.
Total Time Today: 7.75 hrs
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