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Building Bulwarks Part 2 |
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Cutting and Installing the Caprail I started by marking an inch parameter on deck in from the edge of the toerail, and two inches on the topsides down from the edge of the deck. These marks designate where I will grind. Then I began grinding off the Awlgrip and the gelcoat from these areas. I want to see good, solid fiberglass before I start building the bulwarks,
Here I have ground thru the gelcoat down to the fiberglass on the hull flange.
Here I have begun grinding the deck side of the torail. Here is a shot of the topsides with the gelcoat removed by my Festool. You have to get all the gelcoat off if you want the bond of new fiberglass to be strong. I also take the Awlgrip off below the cove stripe since I plan to fill the cover stripe with epoxy. One of the issues I have had with my Bristol for a long time is that of cracks along the turn of the hull like these in the photo. I don't know if other Bristol owners have similar problems--I sail my boat very hard which I think contributes to the cracks. In the past I have tried filling them when I had the boat repainted, but they reappeared. It is only the gelcoat cracking. I think the yard, at least for my boat, made the flange joint extra thick with gelcoat and it simply tends to crack there. The cracks do not extend into the fiberglass. Here is the topsides finished.
Here is the deck edge tapered for fiberglassing and I have fresh sanded the teak toerail. At this point I will begin cutting the teak hawse pipe braces, forward, amidships and aft. Fit them, clue them in place and thru bolt them.
Next, I began fashioning the forward, amidships and stern hawse pipe braces out of teak. As with the starboard side I glued two plants together to get the thickness I needed: the inside plank an inch shorter to account for the toerail. Here are some shots. Then as the Six-Ten began to kick, I measured for the scuppers on either side of the amidships hawse pipe. The scuppers are each 3 inches wide, separated by 4-1/4 inches and are 9-1/4 inches fore and aft of the brace. I found several hull to deck flat head screws which all were tightened an addition quarter turn. I dug out the mastic that seals the hull to deck joint and cleaned everything up with acetone. Then I spooned a loose mix of epoxy and 404 high density filler into the gap that the mastic filled. I will sand everything when the epoxy hardens. The next step is to cut the foam bulwarks that will fit between the teak hawse pipe braces. I used my table saw to cut 4 pieces each 8' long, and notched for the toerail. I pealed the plastic protection sheets off both sides--gluing to the sheets would do no good at all. Then I wet out the top and outside edge of the teak toerail, and to top edge of the hull to deck joint. I used the West Six-10 epoxy to run beads of glue down the rabbit I cut for the toerail, and over the toerail. When everything was ready I pressed the foam boards down onto the toerail and taped it place. Next, I drilled holes into the three teak hawse pipe braces to thru-bolt them with 5/16" 316 stainless carriage bolts. I won't bolt them down until after the epoxy has hardened for about a week or more. Finally, I ran a fillet if the Six-10 epoxy along the inside of the toerail, and used some thickened epoxy to fair the outside of the joint between the topsides and the foam. I would have liked to glass in the foam today but rain threatened so I will do that next weekend. This weekend I applied two layers of 24 oz biax tape and 1 layer of 6 oz cloth to the inside of the bulwarks. I will apply the same lay up schedule to the outside next weekend. You can see some of the lay-up schedule for the port bulwark in the photo. More pictures to follow. The steps to glassing the inside follow:
Here is the inside of the bulwark glassed with two layers of 24 oz. biax and one layer of 6 oz cloth.
The outside of the bulwark with the same layup schedule.
Finally, I trimmed off the excess from the stern hawse pipe brace. I used a Japanese saw and trimmed the brace to the shape of the stern. Here you can see how if follows the same shape. In this photo you can see the cross section of teak and glass.
Here are some additional photos and commentary about building the bulwarks. The specifics of the process are covered in the starboard bulwark webpage. I used the fiberglass "C" section I bought from McMaster Carr and that I used on the starboard side. First I filled the inside corners with a thin fillet and let it set up in the sun. Later I will cut off 3" sections to fit thru the bulwark. Next, I cut the openings using my Fein Multimaster. I had marked on deck where I had cut openings in the toerail before installing the bulwark. The Fein made short, easy and controllable work of it. I cut the "C" section into 3" lengths and installed each--they were proud on each side of the bulwark--and carefully taped around the opening. I drilled a hole down thru the top of the Styrofoam and slowly poured thickened epoxy with 404 high density filler. I used a extra slow hardener because the epoxy will exotherm in such an enclosed space and melt the foam. The extra slow hardener gave me plenty of pot time and did not heat up as it hardened. Here is the outside of the scuppers embedded in thickened epoxy (sorry for the camera shake). It will be sanded fair to the side of the bulwark.
Cutting and Installing the Caprail The caprail will be from the matching teak plantation stock used for the caprail on the stern bulwark and for the cockpit coamings and covering boards. It is 7/8" thick and the boards for the caprail are 9' long and 7-1/2" wide. Before breaking out the teak boards I decided to "practice" using some relatively inexpensive milled pine from Lowes--boards 3/4" thick, 8' long and 7" wide. I positioned the first board at the starboard bow, pinned it with some temporary screws and scribed the curve of the bulwark, giving myself an inch margin outside and about 3/8" inside. Then I rough cut the curve on the band saw and installed. I used a template to mark the one side of the scarf join, removed the board, cut the scarf with a hand saw and reinstalled the board. I followed the same procedure for the second board. I overlaid the forward end of the second board on top of the scarf joint and traced it onto the underside, then again cut the matching scarf with a hand saw. Then attaching temporarily to the bulwark. As you can see, the scarf is unsatisfactory--mostly attributable to my lack of skill with a handsaw. The next scarf I will cut using my Bosch jig saw and straight-edge guides. For the next board I added, I used a simpler diagonal cut scarf, cut with a straight edge and my router. Since the boards are not bent to the shape of the bulwarks, but the shape is sawed, there should be no tension on the scarfs. I will add two dominos to strengthen the joint. Finally I did some experimental shaping to the third board: the results of which helped me to decide the caprails' final width (complicated by the fact that the port bulwark is 1/8" wider than the starboard bulwark) In order to not cut the port bulwark wider which would obviously point out this difference, I plan to cut the outboard overlap of the port side 1/8" less than the starboard side (5/8 to port and 3/4 to starboard). That will ensure that two caprails are the same width, and the overlap would really not be comparable with the boat in the water. The inside edge of the caprails will be cut 1/8" proud of the flush inside, rounded at the top with a 3/8" round over bit. The outboard edge will be rounded on the top with a 1/2" round-over bit and underneath with a 1/4" bit. The round-over's for the captail are the same as the round-over's for the covering boards in the cockpit. The caprails are attached by gluing them to the tops of the bulwarks in thickened epoxy. The bulwark stops are three layers of 6 oz fiberglass expoxied in place tying together the sides to the tops of the foam and teak braces. Then the caprails are screwed down on 24” centers to the teak braces. I will use #14 screws long enough to screw into the hull to deck flange. Here are the steps to fitting and installing the caprails : :
R Rough cut the bevel 1/8” proud and cut to the line using a flush cut router bit. Re-position the second board so the scarf joint is tight, and scribe the inside and outside edges. Here is the first of the starboard teak boards rough cut to fit the curve of the bulwark. For the forward section of the caprail--the first 14 inches I increased the width by 3/4" on the inside, just as an aesthetic feature. The inside edge for the remainder will be flush cut. I then cut the end in a bevel that I will duplicate for the adjoining board.
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