July 14, 2018
Closing in on completion, and no drama mind you (the departure date for delivery being less than a week out), I grabbed the forward seat for the white Dhow and re-installed it. It donned on me, midway through setting the eight fasteners, that I probably should test-fit the mast to ensure the key in the mast step and the hole through the forward seat were aligned and would thereby allow the lower portion of the mast to "seat"into the step. Alas, she fit snugly in her aperture. With that confirmation I completed securing the fasteners.
I also cleaned up the polysulfide squeeze out on the white Dhow's rudder stock brackets, and then removed the tape to reveal the finished transom.
One last item was nagging at me prior to getting on with the day's "meat & potatoes", and that was repairing a mistake I made in the starboard outboard gunwale. When installing the gunwale, I got a bit aggressive for a micro-second too long and ended up punching the drill bit through the assembly. Not to worry. I had a few white oak bungs on hand, and one of them would do just fine. I inserted a 3/8" forstner bit into my drill and opened up a home for the white oak bung. With just a brushing of neat epoxy, I gently tapped the bung into position. I will take care of the portion standing proud tomorrow, and then reapply some boiled linseed oil to the surface.
Okay, now on to what I really wanted to get done today! I grabbed the daggerboard (DB) trunk braces and required installation materials and tools. I set my sight on the white Dhow first, and mounted the DB trunk brace, clamping the aft portion to the middle seat. Through a series of increasingly larger diameter drill bits, I gradually increased the diameter of the hole through the middle seat and the DB trunk brace. The fastener I chose for the white Dhow's Db trunk brace was a #10/24 silicone bronze machine screw, backed with washer and nut.
I completed the installation of both fasteners to secure the aft portion of the DB trunk brace to the middle seat. I then turned my attention to the forward portion of the DB trunk brace, where it mounted to the DB trunk itself. I chose #10 silicone bronze wood screws, with tapered heads, for this installation - two per side. I set the fasteners 4" on center from one another, pre-drilled and countersunk for the heads. These 4 screws forward and the 2 machine screws aft completed the installation of the white Dhow DB trunk brace.
I repeated the exercise for the blue Dhow. The only difference between the installations was that I chose 1/4" silicone bronze machine screws for where the aft portion of the DB trunk brace is fastened to the middle seat.
With the DB trunk braces installed, I conscripted some help in turning the Dhows over so that I could gain access to the hull for installation of the skegs.
My first order of business was to sand the primer around the area that the skegs would be installed.
The sanding necessary in order to create a surface that would promote a good mechanical bond with the planned epoxy-based installation. I thought about 'removability' of the skegs, but in the end I just wanted the skegs / lift handles securely mounted. Heck, if I need to in the future, I will fabricate new ones to re-install. - don't judge :)
I settled on the positioning of the skegs between the two Dhows, and then temporarily secured the skegs so that I could apply a layer of protect tape around their footprints.
Here is the white Dhow's skeg in position, with protective tape applied around its footprint. The tape provides a couple useful aspects - 1. it denotes exactly where the skeg is to be installed, and 2. it protects the surrounding surface from epoxy squeeze out.
With the "where" resolved, I then set out to determine the location of the fasteners to help aid in the securing and installation of the skeg. I took note of the aft seat brace (tabbed to the interior of the hull and located directly beneath the aft seat), and settled on a fairly equidistant location for the four fasteners. Measuring from the aft-most portion of the skeg: 3/4", 9.75", 15.75", and 21.75".
I made marks on the hull of both Dhows and drilled for the fasteners. I also transferred those marks to the underside of the skegs themselves. I did this by again mounting the skegs in their final position, and crawling underneath the boats, I made pencil marks on the underside the skegs. With those marks transferred, it was time to pre-drill for fasteners on the skegs. The bottom the skeg, where it mates with the hull, follows the curve of the Dhow's bottom. The angle of the screw is more or less perpendicular to the bottom of the skeg, and so as I pre-drilled for fasteners, I would need to ensure that I kept the drill at a 90' angle to the bottom of the skegs. In the end, I was successful at this task.
With the fastener holes prepped for installation, I went ahead and taped off the lower portion of the skews (to protect the varnished surface from epoxy squeeze out), and then headed over to the work shop. I mixed ~1/2 ounce of next epoxy and painted this onto the bottom of the skegs as well as the bottom of the hulls. I then mixed another small pot of epoxy, but this time thickened it with 406 colloidal silica and 407 low-density filler. I applied this thickened epoxy to the surface the hulls, where the skegs would be mounted.
I firmly pressed the skegs into position, making sure that I had squeeze out all the way around the vertical surfaces of the skegs. I then went below and mounted the screws through the interior of the hull and into the skegs themselves. I was worried (not having help on hand) that the screws would push the skeg up as I attempted to drive the fastener home, but the pre-drill work paid off here. The fasteners found their pre-drilled homes without incident. As I tightened the fasteners, which by the way have a rubber washer seated just beneath the head of the screw and visible from inside the hull, the skegs were pulled firmly into position on the hull.
The skegs mounted. I will pull the protective tape tomorrow, and paint the bottoms with anti-foul.
The last item for the day was an anticipatory one. I wiped down the hulls, and then applied tape in preparation for painting the bottom with anti-foul. I should be able to wrap up the work tomorrow...unless of course I just want a bit of drama!
Total Time Today: 4.5 hrs
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