Building Bulwarks Part 1
I have owned my Bristol 29 for 21 years now, and have studied her lines, especially her sheer a lot. Since I sail offshore and singlehanded, I've always felt the biggest safely flaw in her design was a lack of bulwarks. For me the cute little teak toerail, one inch tall doesn't cut it. So for this refit I have decided to improve her sheer and build bulwarks
This is a cross section of the idea.
The sheer will be trimmed so that at the bow the bulwarks are about 5" tall, dropping to about 3" at amidships, and about 3-1/2" at the stern. I haven't figured out how to handle the taffrail yet but I think it will be open for about 3 inches on each side adjoining the bulwarks, for deck drainage and for space to mount some serious fairleads.
Today I initially ground down thru the gelcoat on the starboard deck and topsides and began shaping a recess to glass into for the bulwarks. The gelcoat was cut back to the cove stripe and about 4 inches in from the toerail on the deck. I will epoxy glass to about two inches down and two inches in.
Then, I fashioned the bow and mid-beam sections of the bulwarks where the hawse pipes will be located. In the bow, mid-beam and stern sections of the bulwarks I will use teak. This is the bow section, about 16" long by 5-1/2" tall and 2" wide. It is positioned in thickened epoxy. After the epoxy set up, I thru-bolted it at the front and back with 5/16" carriage bolts.
Next, I cut the scuppers for the bulwarks. Two on each side of the mid-beam hawse pipe, each 3" inches wide by 1 inch high. I cleaned out the seam between at the hull to deck joint, washed it in acetone and filled it with thickened epoxy. I added two coats of unthickened epoxy to the edges of the teak and the area of the deck as well. Here is the scupper taking shape--still needs some fine sanding and shaping.
For the sections of the bulwarks between the teak hawse pipe areas I will use Styrofoam. I bought 4 x 8 ft 2" thick slabs at Lowes, and these I cut on my table saw to the dimensions I need. I rabbited the bottom face to account for the size of the toerail. I positioned it place and used lag bolts and fender washers to hold it in place temporarily. Then, I painted the toe rail and the Styrofoam with unthickened epoxy, buttered up both surfaces with thickened epoxy, and screwed the lag bolts down to position it and hold it until the epoxy set up. Later I removed the lag bots.
The interesting thing about Styrofoam is that you can handle it like wood: cut it with hand saws or electric saws, sand it, shape it with a rasp, drill it. It makes a million little loose beads that have to be vacuumed up but it's very forgiving to work with.
After installing the Styrofoam between the teak hawse pipe bracing, I added two layers of biax on each side. Then I installed teak braces every 24 inches that are glued in thickened epoxy, tying the deck, toerail, and hull together. The 2" square teak posts give the foam tremendous strength and provide strong points for me to screw the cap rail to the bulwarks. To add the posts, I cut out a section of the foam slightly larger, cleaning away all the foam that stuck to the teak of the toerail and the hull to deck joint. Then I painted the area heavily with unthickened epoxy, then filled the cavity about a third full of thickened epoxy and pressed the teak post into the mush, being careful to get a good seat without any air pockets. Once it is all cured and hard, I will trim the bulwarks to the curve of the sheer I want.
Today I added a second layer of 24 oz biax to the outside of the bulwarks, giving me two layers on each side. When the epoxy was still tacky I mixed several batches fairing mix with microballons and faired over the biax and the bottom edge against the hull. When it thoroughly hardened, I went after it with my Festool Rotex 150 with 50 grit Saphir abrasive. The Festool took it all down smooth in about 20 minutes of dust-free work. While the 150 is certainly the most expensive sander of its kind in the world, it continues to prove itself to also be worth every penny it cost.
of the bulwarks will be as follows: from the bow going aft 10 ft the
reduction will be 1/4" per foot. Then leveling off at 3 inches for about 10
ft and finally increasing to 3-1/2" at the stern. After I add a layer of
biax to the inside of the bulwarks
The first step was to measure and mark the sheer carefully and align painter's tape to the marks. I gauged it by eye like this photo and adjusted it several times until it just looked right to me. Then, I bought some 8' lengths of molding at Lowes. The molding seemed very consistent and offered a clear straight edge. I measured down from the top edge of the tape 1-1/2" (the inset measurement for the skill saw blade) and screwed the molding to the bulwark. Finally when it established the exact line I wanted, I took my Bosch skill saw, and using the top edge of the molding as a fence and guide, cut the top of the bulwark to the sheer measurement. This weekend, I will add two layers of 6 oz fiberglass tape to the top of the bulwark and finish faring and sanding.
The scuppers need cleaning up, some uniformity and some strength. I fashioned them mostly by eye and by hand and it hasn't worked out very well. So I am taking a different tack. I ordered some U shaped channel fiberglass stock from McMaster Carr. They have several sizes and I found one that was slightly narrower than the existing holes and a bit taller. I cut short lengths of channels to fit, and opened up the scuppers to the required height. Then, I glued them in place with thickened epoxy.
I will sand the channels flush with the bulwark when they are fully cured.
These are the hawse pipe fittings I will use. I have 12 of them. They are made by Seadog, 316L stainless steel. The depth is 7/8" so they will fit almost against each other on each side of the teak bracing. To position the fittings for cutting the holes I decided to orient them 1/2 below the top of the bulwarks, and marked a reference line to that effect. I will cut the open by cutting holes with a forstner bit the size of each curved side of the fitting and then cutting between the holes with a jig saw.
So I began by marking an upper margin for the top of each hawse pipe. Since the bulwarks are different heights at each hawse pipe location I felt that to continue the scale of the sheer the upper margin had to be so inclined as well. I first marked the aft hawse pipe and cut the two round holes thru the outer glass layers with a forstner bit. I then decided that I had located the holes too low on the bulwarks, so I filled those two holes.
I then marked each hawse pipe location with what I felt was a good aesthetic margin based on the height of the bulwark.
Thus I began working on the mid spring hawse pipe. Instead of the forstner bit which took forever to cut, I used a 1-3/4" hole saw, which took almost forever--literally about 45 minutes to cut thru each side of the hole. I used the same size bit to drill all the way thru the bulwark and then back cut the holes from the inside to make a cleaner cut. I used a cordless 18 volt drill with a built in level to keep the hole in alignment. It worked very slowly but very well.
Once the first hole was cut, I turned to the second hole. and when that was cut thru I used the hole saw to cut a middle hole. The middle hole was infinitely faster and more accurate than using a jig saw thru two inches of teak and 24 ounce biaxial cloth.
I used a hand rasp to square up the hole and fit it to the hawse pipe. Here you can see the hawse pipe dry fitted. And, of course, once everything fit as it should, I painted the interior with the first of three coats of unthickened epoxy. The one hawse pipe opening took an afternoon to do so I will tackle the other two this coming weekend.
This is one of two stern anchor fairleads I will mount in the dewatering openings in the stern bulwark. To mount them firmly I will overbore the mounting holes, fill with a high density thickened epoxy; and then re-drill and tap the holes.
I used a 1" spade bore to cut the holes, each about 1-1/2" deep. Here is the port side. Then I filled the four holes with a thick mix of epoxy and aluminum powder (the highest density thickener I had on hand). After the epoxy hardened I repositioned the fairleads, remarked the 3/8" holes and drilled them about 1/8" deep. I will drill and tap the holes after I finish painting the decks.
The taffrail turns out to have been very poorly built by the yard. The turn of the hull at the hull to deck joint, under the teak toerail has a large void at the point where the back stay chainplate makes the turn over the toerail. This constant pressure from the rigging had actually dented the hull flange under the chainplate. I have always known something must be amiss but not until I started fairing through the gelcoat did I discover how poorly that part of the hull to deck joint is. I cleaned out the void and filled it with thickened epoxy. When it hardened I shaped the flange back to the way it should be with a sander.
With some chisel work I opened up the flange under the toerail and dug out all the old mastic--still soft, gooey and sealing I suppose, but I want to bond the hull flange, the deck flange, the toerail and the bulwark I will build all together. I glued up some pieces of teak for the two ends of the taffrail and the center area which will take the pressure and stress of the backstay chainplate. These will be cut roughly to pick up the angle of the transom and extend that angle up 3-1/8 inches. Between the teak. I will add Styrofoam as I did with the starboard bulwark.
I began with the teak end cap for the starboard side. I made a cardboard template of the notch needed for the toerail and then cut one of the glued up pieces of teak on my band saw roughly to fit. I drilled a couple of holes for temporary screws to hold it in place until the glue kicked. Then I wetted out the surfaces with epoxy and then sat it down in very thick epoxy and ran the screws in just enough to hold it in place.
Next, I cut the middle teak brace to fit using the same template. This teak will take the pressure of the backstay chainplate and needs to be mounted very strongly. Again, I wiped down everything with acetone, wetted out the surfaces with epoxy and mounted the teak in heavily thickened epoxy. I used some tape to hold it in place. By this time it was almost dark.
Today I spent a few minutes shaping the two teak braces I had previously glued up. I used a Japanese saw to cut the the outboard angle on the starboard brace to the angle of the transom and sloped the inside angle the same using a belt sander. I cleaned it up and rounded it a bit with the belt sander.
Then I used the belt sander to add the same slope to the inboard center brace. Finally I drilled two holes for 5/16" bolts to mechanically tie down the center brace to the deck. It's probably unnecessary but it's easier to do it now and only took a minute. The 5-1/2" bolts are submerged in thickened epoxy.
The next step is to mount the port teak endcap. I temporarily screwed it down to hold it in place until the epoxy kicked. I cut the outboard angle with a Japanese saw and used my belt sander to shape the inside bevel.
Now, for the top layer of Styrofoam. I cut two block large enough to fit the Istarboard and port sides of the stern bulwark and trimmed them to fit with a Japanese saw. wetted out the surfaces with unthickened epoxy and and made up several batches thick enough not to be runny to bed the two foam pieces in. After the epoxy dried, I sanded the foam and teak with 60 grade sandpaper on a palm sander. The foam can be smoothed and shaped very easily and controllably this way. To end the day, I added one layer of 9 oz cloth over the foam to protect it from damage.
The next morning I began glassing two layers of 24 oz bias to the bulwark, over the single layer of 9 oz fiberglass tape. I first built up a nice fillet on the inside joint of the toerail to the stern deck. I then painted the front and back of the bulwark with epoxy and when both the unthickened epoxy began to kick and the fillet was at the rubbery stage, I laid on the biax, smoothed it by hand and painted on enough fresh epoxy to saturate the cloth but not to have epoxy running out of it. When all the glass is hard, I will trim off the excess with a Japanese saw.
Later in the afternoon, the epoxy had hardened and I used my saw to trim off the excess cloth around the bulwark. Here are some shots of it, ready to fill sand and be done with it.
Today I painted part of the stern deck and the stern bulwark with System Three WR-155 epoxy primer. Two coats took most of the afternoon to dry. The primer is a high build primer that sands very easily. I will sand most of the primer away to be sure and catch the slight high spots.
Fitting the Stern Caprail
Today I began installing the caprail for the taffrail bulwark. The taffrail has a compound curve and to help ease the bend in the teak I have had the board suspended with about 30 pounds of weight for the past 6 months. Today I rough cut the inside curve, and because I needed more width than I had in the board, I glued the straight edge of the trimmed piece to the back side of the board. I used Titebond III for the glue.
Here the board is positioned correctly and bent into position with a heavy concrete block on each end. I need to order some 1/4 inch by 2 inch self tapping screws before I test mount it. In the meantime, here are some photos of the board in position.
The next step in attachment is to drill the holes to secure it. I set it up aligned and weighted with a cinder block and an old battery, and drilled the holes #14 for 316 stainless 1/4" x 2" screws. The aft screw at each attachment point is slanted to assume the angle of the stern. Once everything was predrilled and counter sunk to the depth I wanted, I painted both the bottom of the caprail and the top of the bulwark with unthickened epoxy and left it for a while. then I mixed up a total of two large batches of very thick epoxy, thickened with West 404 high density adhesive filler, and slopped it on the top of the bulwark. Them I reattached the caprail. weighting it again at the ends, and screwing it in place. Most of the epoxy squeezed back out so I carefully caught all of that with a squeegee and cleaned up the top and bottom edges.
After the epoxy had completely kicked, I removed the weights on the ends, and rough cut off the overhanging board. I used the edges of the two boards next to the cut to cut 1/2" bungs for the counter sunk screws. I glued the bungs in with TiteBond III.
After the glue set, I drew an outline of the aft curve, taking it off from the transom underneath the caprail, and cut with my jig saw. I wanted to get the basic shape of the caprail early so that I could address how I would support the backstay chain plate. Before I began the stern bulwark, I discovered that the chainplate had compressed the turn of the hull to deck joint because of some voids. I want to back up where the chainplate overlaps the caprail, to brace the fiberglass, so the finish on the caprail can be renewed without removing the chain plate. I trimmed the aft edge of the caprail at the chain plate back to the hull and fashioned a piece of 1/4" thick fiberglass to the height of the caprail and glued it to the teak with thickened epoxy. When it hardens I will shape it with my belt sander. It will get painted along with the topsides, the adjoining teak will be finished bright.
After some time with my Festool Rotex 150 I arrived at the basic shape I wanted for the caprail. The forward edge assumes the same angle as the front of the bulwark. The aft edge is nicely bullnosed. Here are some photos. This teak you may notice--which is part of the purchase I made for all the teak for the caprails, covering boards and coaming--is plantation grown teak, much more blond with streaks of pink and less brown than Burma teak. I really like the light color and contrast to the darker teak used elsewhere on the boat.
This weekend I completed the final filling and sanding using an air driven board sander. One of the time consuming aspects of the starboard bulwark that I will not repeat on the port side is using the 24 ox biax as a final finish layer of fiberglass. On the stern bulwark I added a layer of 9 oz cloth over the biax when it was still green and the cloth made a much smoother and easier surface to fill and finish. In retrospect I wish I had thought to do this to the starboard bulwark as it has consumed too many hours filling the rough surface of the biaxial cloth. I am learning as I go so at least the port side will be faster to complete.
Once I finished sanding everything smooth with 60 grit paper, I applied three coats of System three Silvertip water-based epoxy high build primer. It dried almost at once in the temps today, and I was able to apply three coats within an hour. I then went over the surface and filled some very small pin holes (from the biax) with a thin mix of epoxy and West 410 Microlight filler. I will sand the filler smooth during the week. Here are some photos showing the bulwark and the transition from the hull to the bulwark. I like the results
If you are familiar with Bristols and the B29 specifically, you may have noticed that I filled in the cove stripe. Bristol molded a nice half round cove stripe into all of their hulls, but unfortunately, the cove stripe on my boat does not follow the new sheer, and it was really too low in relation to the bulwarks, so I filled it. I may add a new cove stripe, but it would be some sort of Mylar tape if I do.
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