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28 foot Crusier


Scott Dunsworth

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Scott:

I presume that is the keel deadwood and an additional lead keel will be bolted below?

Did you use plywood or solid stock?

Did you glass under the keel to isolate it from the internal keel plank or glue straight to the internal keel plank (keelson?)?

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It will be bolted through from the lead.

The center of the boat has two layers of the 17 oz overlaping. It was sanded with 40 grit and the keel flat epoxyed into place over the planks and glass.

Its made from yellow pine 1 1/4 inch thick, each layer will be until the whole keel is laid up.

I am going to try to give Graham a interior layout, the amount of tank-age that I would " like " to have soon. That way I may not have to build the whole keel from wood, then cut off a portion for the lead mold. He needs this information to balance the boat with the lead section of keel. Then I could fashion the lead part from blue board for the mold.

I would like to have two water tanks of 25 gallons each, a fuel tank of 30 gallons and a holding tank of 15 gallons.

30 Gallon fuel tank would give me a motoring range of around 400 miles. The two water tanks would allow us to stay out over a week without getting overly conservative with the water.

I haven't researched it yet but we are thinking about the tank-less system instead of the holding tank. It treats the waste mechanically and chemically then discharges it straight overboard. As I understand it the system is USCG approved, but may still be illegal in some areas, or just not right thing to do.

Scott

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I found a system that incorporates both. Very expensive but it would be nice. It has a 7.5 gallon holding tank for no discharge areas or you can unlock the discharge system and it's legal everywhere else. You wouldn't have to be 3 miles off shore. USCG approved, the waste is supposed to be well within the pollution limits of the US.

I believe in doing the right thing if at all possible. But sometimes I think boaters get a bad rap for a lot of the water issues. For example, I live near the Ohio River, we have a large city up river that every spring ends up dumping a million gallons of raw sewage in the river. Their system wont handle it all with heavy rains, so they just pay the fine every year because it's cheaper than upgrading their sewer system. That's not the right thing to do, but they do it year after year.

The only down sides I see to this tank combo is the price and I would rather have the tank a little larger.

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FIFTY gallons of water for a week?? Oh boy do you use water!!!

Tehani carries 35 gallons in fixed tanks, and about 10 more in half gallon jugs. Good for close to a month with two aboard.

Fifty is a great amount, but I suspect you'll find it goes a LOT further than you think, even not being particularly frugal.

Also- I found that having the boat pumped out was a less onerous task than dumping. Many places have "do it yourself" pump out stations and many are only $5. Of course in the Bahamas, you must have the ability to self pump- no pump out stations there, except one I heard existed in a marina at Nassau- one of the $$$$$$ ones.

Also - off the Florida lower west coast, it's not 3 miles- it's 6 miles.

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Scott:

Splitting your water tanks allows you to use only one, or both and helps distribute the weight more. Beyond that, I'm hearing more and more that a lot of people do not drink from their water tanks, as over time, water quality diminishes. They use plastic jugs for drinking and some cooking water. On the Princess 26 I'm planning, I'm thinking a single 9 gallon tank under the galley and had planned on a supplemental 14 gallon tank up front. Will probably pull the plug on that in favor of a couple milk crates which will hold eight single gallon jugs. Not only does that help you with usage, but water quality at marinas can be suspect. With jugs, you can see and taste what you are getting as you fill up.

I think water usage also depends a lot on the personal preference, the crew and personal habits / expectations. Showers, for example. I have a "shower" on my existing 17 footer, but it's a 1/2 gallon garden sprayer. Fill it with warm water, wet down, lather up, rinse off.......all in the cockpit. Works for me, but I'm not too particular about those types of things. Lady I'm married too will have none of it. Marina shower for her or she goes home. I single hand a lot.

On the toilets, do look into the dry composting types. I hear they work well and Peter has on for his Princess 28. (he may have been using it enough already to have experience he can share).

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On the keel, as I read the plans for the Princess 26, I am to plane a flat spot on the bottom of the boat to mate the external keel deadwood to the internal keel planks. It does appear to me the plans specify that glass is layed in place before the keel deadwood goes on, but I'm not sure why. Presumable, the flat on the bottom of the boat is planed to mate exactly with the keel deadwood as far as shape is concerned, It would appear to me that a better join/fit would be obtained by simply gluing them together as part of the lamination, and putting a big fillet at the base and glass around the sides and on the bottom of the keel deadwood. But that makes it a permanent part of the boat. Putting the glass underneath and bolting it all on with something like 3M 5200 to act as sealant and adhesive might be the intent. That way, you could remove it somewhere down the road if you wanted to. Something I need to visit with Graham about.

On the lead keel "blanks" and keel deadwood, it looks to me like those are all formed, shaped together as one piece, then there has to be a way to split them. My way is to bolt the individual planks together first, then mark them out and shape them all in one piece. The bolt holes will be drilled in the planks first. That way, they all line up square when layed up. Those would also be used to drill square pilot holes through the internal keel planks, so as to mark the locations for the floors inside the cabin. Eventually, you have to have square bolt holes through the lead keel, keel deadwood, keel planks and floors. That is the best way I've come up with to get them all lined up square. Because the keel layup would be bolted together to shape it, it would come apart pretty easy. Of course all the keel deadwood, internal keel planks and floors all have to be drilled out oversized, then backfilled with epoxy and drilled out again. That is a lot of drilling and a lot of chances to mess something up!

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Of course all the keel deadwood, internal keel planks and floors all have to be drilled out oversized, then backfilled with epoxy and drilled out again.

Is this what Graham is advocating? I have no doubt that epoxy is the best way to prevent rot and preserve the lamination integrity for plywood. But considering the chances for a void in the epoxy in the solid wood, especially the holes, is it really better than just using red lead and a good rot resistant wood for the solid components?

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I don't think the P26 plans are that specific. Drilling everything (keel deadwood, keel planks and floors) out oversized and backfilling was my plan. That is also the plan for the pivot pin holes for CB and CB trunk , and that is specified on the plans.

My rule of thumb is that just about every hole in wood or plywood that is exposed to weather or submerged in water gets drilled out and backfilled. That is the only way I know to seal up and encapsulate the wood to keep all moisture out. My concern is not only rot, but expansion due to moisture and the potential for failure of glue lines.

The plans do not specify treated wood for the keel deadwood, but I'm going to use it if I can find quarter or rift sawn stock in the right sizes. The assumption here is it will be glassed over and sealed up, just as the CB will be. It not, and it gets wet from exposure, then I would think it can't be glued at all, else it will expand and the glue line would fail. If not glassed and intended to be wet, then it needs to be made from treated lumber and most likely old stuff CCA. Again, one more thing to clarify with Graham, but I'm pretty certain it is to be completely sealed up.

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On my Belhaven Graham had me plane a football shape flat first, then glass the bottom, overlapping the center line. Then build up a keel flat for the dead wood and lead shoe. I don't know about the Princess but I would bet he's going to tell you the same thing. The dead wood was bolted through with 1/4 inch all-thread in oversized holes that was filled with straight epoxy. The lead shoe was through bolted with 5/ 16ths bolts in oversized holes that were epoxy coated. I simply put a piece of tape over the bottom of the holes filled them with straight epoxy, letting the wood soak up the goo for about ten minutes. Then I removed the tape and let the excess run out. The lead shoe was then bolted up with the top of it coated with 5200 along with the bolts.

On my 28 the whole keel will be bolted through and substantially glassed in. I think the basic hull will have more structural integrity being glassed under the keel and over the keel.

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That is also the plan for the pivot pin holes for CB and CB trunk , and that is specified on the plans.

Those are different though, you are creating a bushing for them to deal with wear of pivoting, the loads are on the blades, housing and trunk For the keel the loads will put serious pressure on the epoxy, and epoxy is brittle.

I don't question this from a point of knowledge of the best technique for this, it just goes against my experience with conventionally framed wooden boats.

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Howard, I recommend grassing the hull bottom before the keel flats are put on. These keel flats will swell and move with variation in moisture. The glass will form a barrier to protect your hull ply from that.

Also as Scott mentioned, grassing the ply will substantially stiffen the hull.

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Brent and Scott:

From the way you describe it, the keel deadwood is just that......deadwood, and not an integral part of the hull. Essentially, just a spacer bolted to the bottom to lower the lead keel to give it a longer lever and greater righting moment for stability. Bedded in 5200 and bolted to the hull will offer structural benefit, but probably not as much as if it were epoxied on and glassed in. Maybe not enough to matter?

To Dave.....as I read the P26 plans, the keel bolts run through the lead keel, keel deadwood, internal keel planks and floors supporting the cabin sole. All the weight of the lead keel is hanging on those 7 or so 3/8" bolts (or more accurately threaded rods). The force of the hanging keel is thus in tension and is carried by the threaded rod, through all that to the floors. The only time I can envision sheer force is when the boat is heeled way over, with the lead exerting its leverage, or perhaps during groundings. Apparently, bolting all this on is strong enough to counter that as well. But I can't see any of these forces being as great as what is on the CB and CB trunk bushings.

From my experience with a glass boat, anytime you punch a hole in a boat, you open a pathway for water to enter. In short, holes in boats leak. Best way to eliminate the water is to first eliminate as many holes as you can (only holes below the water line for the Princess I intend to build are those holes for the keel bolts) and if you do open a hole, best seal it up with epoxy, so when water does enter, it bypasses the wood or plywood core. Better to deal with water inside the boat than water in the core, which is why I almost always drill oversized holes and backfill them with epoxy before drilling the final hole.

Related to this is fasting bolts/screws to structural members that are exposed to weather or are below the waterline. When I can, I like to drill oversized holes and backfill them with epoxy, with the bolt or threaded screw set it place. As a fastening method, its remarkably strong and again, eliminates water getting into the wood. The folks at West Systems have done some interesting tests on the strength of this method.

http://www.westsystem.com/ss/testing-large-bonded-in-fasteners/

Perfect place for these methods will be on the lifting tackle for the CB, which operates in a wet environment with heavy loads under tension.

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To Dave.....as I read the P26 plans, the keel bolts run through the lead keel, keel deadwood, internal keel planks and floors supporting the cabin sole. All the weight of the lead keel is hanging on those 7 or so 3/8" bolts (or more accurately threaded rods). The force of the hanging keel is thus in tension and is carried by the threaded rod, through all that to the floors. The only time I can envision sheer force is when the boat is heeled way over, with the lead exerting its leverage, or perhaps during groundings. Apparently, bolting all this on is strong enough to counter that as well.

Completely accurate, and that sheer force should be minimal. Steel and stainless rod has been doing the job that way for many years.

But I can't see any of these forces being as great as what is on the CB and CB trunk bushings.

There is virtually no load on those bushings, just the weight of the hanging board, or the jolt of grounding. While sailing the loads are trying to snap the board where it exits the trunk and twist the trunk itself at the bottom. The later is reinforced by a thwart, so this may be minimal. While sailing to weather you could remove the bolt and the board would probably stay there ( though the boat would likely leak). Virtually always, the failure of a centerboard system is that the board breaks right at the hull.

Epoxy saturation might very well be the best method. I just can't help but question some of the new techniques that concern wood. It is my nature. Wood expands contracts and moves inspite of our best efforts. There is moisture in it when you seal it up in epoxy. I would suggest gooping the bolts into the holes as well. Polyurethane adhesive bedding is elastic and will stand up to movement from loads, epoxy may not as it is very brittle. Bilge water, though you hopefully will keep this to a minimum is a concern for getting to the bolts and into the holes. $#it happens.

Laying out, fabricating and installing the keel is in my opinion the most daunting of the challenges of the boat you are building. My best to you in this endeavor.

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At the risk of hijacking Scott's thread, I would suggest the only aspect of laying out and building the keel portion of the boat that has given me any concern is the part about pouring the lead keel itself. My guess is, the day that happens, the pucker factor will be running high. I can see a lot of things going wrong with that stunt.

On the CB, I'd love to hear a scientific discussion on the source of the loads and where all the stress occurs. This aspect of the design has been my #1 concern from day one. From a layman's perspective, there would appear to be a tremendous amount of leverage exerted by this high profile board. With the board fully down, there is almost 5 feet of exposed board in the water and only 9 inches or so buried in the CB trunk and only 3 to 4 inches to the CB pivot pin. Seemingly, a lot of leverage, but that may not be the case. As I understand it, the CB pin transfers a lot of the leverage to the CB trunk, which extends up to nearly 2 feet, and is reinforced with doublers and also in a horizontal plane by the hull bottom and top of an adjacent bunk, and vertically by using dividers under the bunk. That leaves a lot of force on the edge of the lever (CB) and fulcrum of the lever, which is the edge of the hull at the CB slot, but that also has a thick fill of epoxy and is backed up by four layers of biaxial glass. The widest part of the CB itself is also at the slot......almost 18 inches, and at that point is not shaped, so is the full width of the board. My guess is the only real danger of any damage from loads would come during a grounding, especially if the boat was crabbing sideways or making leeway, such that the board was being bent sideways vs up and back. I know I've had enough concern about damage to the board that I've already decided to build two and keep one for a spare. Same goes for the blade on the rudder. While I'm at it, I'll build two.

One thing you can do if in water shallow enough to be grounding all the time and that would be to pull your board up some. Not only would that shallow it out and sweep it back some, but a partially retracted board would exert less leverage on the board and CB trunk and greatly increases the contact area of the board to the CB slot edge. The negatives are it could reduce the lift of the board, inducing more leeway, but also the balance of the board with CE of the sails. If you can't trim that out with the sheets, a reef in the main might do it. If that doesn't work, there is always the motor.

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Howard my dead wood, the fin part of it was totally glassed in. After the first piece of 3/4 inch stock was installed I just kept laminating layer after layer till I got to the specified keel dimensions. It was bolted through, faired then totally glassed into the hull as a permanent part of the hull. I have a picture of it during construction, I'll try to post here in a little bit. The dead wood built this ways is extremely stable, six or seven 3/4 inch thick lamination's basically give you a very thick plywood dead wood with a water proof seal in between each layer.

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Scott:

So the deadwood on the Bellhaven was a stacked lamination of 3/4" solid stock yellow pine and on Candice its 1 1/4" solid yellow pine? The latest reference to "basically, a very thick plywood" threw me for a moment, thinking it was a stacked lamination of actual 3/4" plywood layers.

But in both cases, you did what I had thought, which was fully glassing the deadwood portion to the hull, making it a permanent part of the boat and not a bolted on spacer. That makes much more sense, even if you do glass under it first.

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