Construction - V


Progress Report - Apr. to June 2000

Recently I was able to get my hands on a demonstration copy of Vacanti's Prolines 98. Heck, you can even get it yourself at their website. The demo version does not allow you to save your work, but I was able to enter the lines of my boat in about an hour. Once entered, the program gives a 3-D perspective of the hull (you can do the deck also if you have the full version) that you can turn and play with like a toy model. That's nice, but the real meat for me was the hydrostatic calculations. I put in the ballast (weight and location of each grouping of ingots), and then watched the program churn through the convolutions of slowly tipping the hull over. Now, lots of questions came up in my mind, like how does the program determine the CG of the hull without the ballast? But let's not allow the nitpicking facts get in the way of a good story. Based on this data, the program concluded that my vessel would reach its point of no return (capsize) at around 130 degrees. Whoa! That's better than many ocean-going yachts. Okay, back to reality. A more useful benefit from this exercise was showing how the hull tips in the water given a displacement of 1600 lbs. Specifically, the rail (or gunwale) touches the water at around 40 degrees of heel. That's pretty far over, by gum. After a few more experiments the program locked up, probably due to some internal demo clock so you couldn't design the next Carnival Princess.

All of this was an interesting sideline. I plan to conduct my own real life stability tests as part of the sea trials, but having this in hand will provide an intellectual comparison.

We'll start off here by showing a picture of the interior again, this time with the lockers in place (the piece below the elliptical porthole) along with the head and galley tops glued in. All surfaces have been coated with epoxy in preparation for a primer coat. Contrary to most everything else, the bottom of the lockers are not held in place by a cleat. I had to anchor them in place with a couple of nails while I applied a fillet on one side. After that solidified I pulled the nails and put another fillet on the other side.

Also visible here are fiddles installed on both the head and galley (shown in the lower left corner of the pic). Hopefully these will help keep things from flying around in a seaway. Later I will install several padeyes around the head hatch so I can tie things down, like a stove or porta-potti.

Time for the cabin top. Here's the first sight of my lead ingots, put to good use to hold down the 1/4-in. plywood until I can get all the screwholes drilled. Despite the amount of curvature and having a bit of compound curve near the forward end, the ply never complained. Warning - this stuff is 3 ply; the grain of 2 veneers run in the same direction. That means it will bend easier along one axis than the other. In this picture the grain of the 2 veneers is fore and aft.

One thing to be careful of here is making sure that all surfaces of the ply are snug up against all supports when you pre-drill the screw-holes. Also, start at one end and progress to the other. Otherwise you run the risk of the screw-holes not lining up properly.

And here are both sides completed, trimmed and sanded clean. The second half was more challenging because I couldn't use C-clamps on the center stringer. Instead I had to use 4 or 5 screws. Not a big problem, just a bit more awkward.

Now I had a choice. I could either glass the cabintop and then install the hatchrails, or the other way around. I decided to put on the hatchrails first, because I prefer to have wood to wood glue joints wherever possible. Whether this really makes any difference, I don't know. The only other thing left on the cabintop will be the handrails, and I'll put those on after I glass.

After this stage, I had to put a doubler in the inside aft 12 in. of the cabintop. This is designed to provide reinforcement for the cleats that will hold the running rigging. So the question was, how do I glue a piece of ply on an inside curve without punching holes in for screws and nails? I came up with some "stilts" that I could rest against the furniture inside and force the ply into position. Well, I guess it's hard to describe without seeing it, but it was a pretty simple setup.

Through the miracle of time elapse photography, here we have a sequence of how the cockpit went together.

Any questions? The leftmost is the cockpit at the time of the previous page. The middle has the outer cockpit railing, cockpit well sides, and traveller beam installed. The cockpit seat is also done, although that's harder to see. The rightmost has the cockpit coaming complete except for the rail cap, all cockpit hatches in place but not attached, and the cockpit floor is done. Notice the hatchboards as well. There were no surprises here, just a lot of little piece work. The only tricky part was fitting and glueing the cockpit floor, which is one continuous piece. Several steps were required to get the floor ply around the permanently installed traveller beam.

Here's a closer look at the cockpit seats. Each hatch has a frame around it to help seal it from water ingress. Although the aftmost hatch looks restrictive, it's still big enough to be able to reach most of the compartment below it. Remember that I have no limberholes in the bulkheads, so water will have to be sponged out from each section. The other hatch openings are big enough to reach everything easily. That comes as a relief, since I was concerned about having to become a monkey to retrieve an errant item underway.

The coaming carlin is still overlong after glueing the outside ply in place. I trimmed it down before glueing the inside coaming section.

Looking on the other side of the coaming, here's a closeup of the oar socket. There is still a 5/8-in thick rail cap to be glued on the top of the coaming, which is why the block sticks up a little bit. My intention here is to reinforce the oarlock location and spread the load over a wider area. Whether this is enough will become apparent when I actually use them. If I rip them off, well, I built the boat, so I think I can handle fabricating another solution.

It's hard to tell here, but the oarlock is installed at a slight down angle. I drew a diagram of the boat and a set of 9.5 ft. oars to see what it would look like. Due to the freeboard, it's a pretty good angle. So I set the socket around 8 degrees so it would prevent the oars from binding on the oarlocks.

So let's talks decks since we can see some deck next to the coaming. This picture shows the foredeck after it was glued in place. A butt-block is glued to the underside to take the next deck section. You can see primer on the interior. The next deck pieces I primed and painted the undersides since it would be more difficult to do it when they are installed. But there is a hazard with this plan. After they are glued in place, there is more filleting done inside. Those fillets, and other missed spots, have to be primed and painted also. In the process, epoxy, primer, and paint drips onto the parts already painted. So I have to go back and repeat the whole process again. So after doing the starboard side like that, I'm glueing on the port deck with just an epoxy coating. I'll take care of all the remaining priming and painting in one shot.

Speaking of painting, I've pretty much stuck to my proposed plan on the previous page. According to the Interlux literature I only needed one coat of primer (yes!). After 2 coats of the enamel, I think I'll probably need another coat in certain places to make everything look, well, truly snazzy.

Before I leave the foredeck, I've received the mast tube and associated metal pieces from a local machine shop. I needed the tube to accurately cut the hole in the deck and the brace near the mast step. Once cut, I was able to fit everything in place with satisfaction. I won't permanently install this part until after the deck is fiberglassed, primed and painted.

And finally, this picture shows 2 things completed--the hatchrails and the whole starboard deck. I'll say right up front that the fact that the hatchrails are perfectly parallel is a complete fluke. Measuring with accuracy on a slowly adjusting curved surface was hard work. I just did my best and crossed my fingers.

And the deck? Easy as pie. I used those cut templates that I described before and they helped tremendously. On the underside I have glued reinforcement blocks for cleats (the horn variety) and U-bolts. The U-bolts will be used to tie down a boom tent (an upgrade that I'll eventually get but I'm planning for it now) or an occasional fender. I also glued a couple of blocks for potential stanchions for lifelines. I don't plan to put lifelines on this boat, but if I'm forced to (at gunpoint), I'll have the extra strength there.

I can't describe the feeling of satisfaction after putting on the deck and standing back to admire it. It seems like getting it fully enclosed is the first step to getting its personality. No longer is it a random pile of boards cut at strange angles, or a skeleton with no comfortable way of getting around. It now has a skin to show the true purpose of its design.

Another thing has happened that is purely an illusion. Before, it looked ungainly, huge, any moment about to swallow my garage. Now it looks a lot smaller, a lot more manageable, and the garage doesn't look so threatened. I'm sure that when I move the boat outside, it will look vastly smaller, at the launch ramp a small toy, on the ocean a minute plankton. But it will be my plankton that I had fun creating.

At press time I'm about to finish the rest of the deck, then I'll finish the priming and painting of the inside. After that I'll have no choice but to fiberglass the deck, the cabintop, and the cockpit. Oh, Boy!


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