21st Century Daysailer/Weekender

true...it's a good thread you started ...I still like my polyethylene idea above...but nobody else seems to have taken to it...maybe around 16-17 feet...

"... daggerboard-equipped, beachable, rowable, polyethylene molded sprit-sail rigged water-ballasted boat with some permanent reserve ballast to increase safety and with built-in flotation and a small cuddy cabin...some good storage areas for camping gear..not much teak trim here...just basic and they'd all be white with some racing stripe decals of various colors...would it be do-able? I think something like this might sell to the kayaker who wants more......."

I think if you could make one for under 6 grand..the kayak folks looking to move into the sail scene might make them fly off the shelves...famous last words....There would have to be a trailer so keeping it under 6 grand would be tough...they would be roto-molded I guess....just what the world needs though...a few thousand 16 -foot hulking piles of polyethylene crap...but still...

 

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Sounds interesting but I don't know enough about the material and how the process affects design to be able to intelligently comment on whether its possible or not. The basic concept of an inexpensive daysailer is a good one.

 

Thanks for the kind words.

I'm thinking rugged construction kind of rules planing hulls out.

They can be rugged and light, but not rugged, light and cheap.

Once you give up planing, you can do with a smaller, handier rig which is less scary for general use.

Of course we can keep a few of the scary boats around for thrill seekers who are willing to pay. Just keep enough of the rugged ones around so they can rescue the scary ones that get into trouble

 

Good comments...I was just a bit surprised that the San Juan couldn't hold up but there may have been previous existing damage or maybe there just isn't much support floor up near the bow in those boats though they have a good reputation...It made me concerned about my Hunter 20 in those kind of conditions...i.e. - but that is very rough stuff for production boats..even beefier ones from the seventies ....when the winds at 25 knots and your racing her hard...Well..she got them to safety..not like she unzipped like the Titanic but enough to be very "interesting"...and also interesting to me... who as I said has a probably lighter-built ' 83 Hunter.....I do have a decked vee-berth ..some boats don't have a berth..just open vee-shaped stowage behind a bulkhead up there...more prone to oil-canning etc...the SJ may be one of them...I've been meaning to do some photo searches...fire up the search engines scotty....!

p.s.-....okay...no..they have a good vee-berth for lower bow entry support..she may have just been an older '73 or '74 that finally gave it up and cracked...or they could have hit something...doubtful though...I think she'd just been raced alot as so many SJ's have...racing can take a hard toll....I'm fairly confident my boat was used for fishing in the bay more than racing...lol...nary a ding on the hull gelcoat when I got her...who would want to race a H-20? Afterall..they're kinda fat and a 5.2 hull speed...just fast enough to get out of her own way when she has to...I like my boat...

 

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Paul Riccelli (PAR) gave me permission to post this very innovative design some time ago. He also took the time to explain the detailed features of the boat -particularly in the area of the rudder.
I am very saddened that Paul has left this forum due to the rampant personal attacks so obvious in various threads. I hope everyone will read Will's "Shape up or ship out" post's partiularly the one under "Boat Design" with the quote from "Marshmat". http://www.boatdesign.net/forums/boat-design/shape-up-ship-out-31421.html
We can all do better in treating fellow posters with respect!
I hope people will remember Paul thru many of his generous comments and thru his innovative design in the RYD 14 posted again here!

 

My ideal coastal camper

I'm looking for a coastal camp cruiser and as mentioned, one of the primary concerns is the head.
My wife seems to have a teaspoon sized bladder while I have the great joy of suffering from lactose intolerance, food allergies, and plain old IBS - just to top off the fun. So for us, a user-friendly head arrangement is not a nice to have, it's a must have. I am also 6'2", which further complicates the issue. Normal sitting headroom for me requires about 4 - 4.5 feet.

Needless to say, I have seen nothing under 24 or 25 feet that has the room. A Mac 26X would be nice, but just more boat than I care to acquire at the moment.

I've been sketching for a while and came up with a trimaran, or outrigger-stabilized mono would be more accurate. This hull would have an external rotating leeboard and a box keel to free the cabin of intrusions into the living space. Debating an A-frame mast too. Overall dimensions would be 21 feet LOD, 12" draft, and 5 feet max beam for the main hull. Rudder is transom hung and kicks up, so beaching will be possible.

Displacement is carried in the box keel that would be approximately 20" max beam to allow the installation of a proper marine head, roughly 5 - 6 feet back from the bow, just behind a bulkhead to which the forward outrigger beam would be mounted. The head compartment would be 4 feet long. With the 20" width and 12" depth of the box keel, I could install a marine head and have reasonable sitting room if the cabin above the box keel is 3 feet high.

I'm left with about 11 feet of cockpit aft of the head compartment. I haven't decided whether to continue the hard cabin further aft or if a canvas cover would be the best choice.

I'm also trying to decide if adding rocker to the main hull would be worth the effort or just building a flat bottom and fiberglassing the box keel on to that. I'm concerned that the flat bottom might not handle much pounding without being very strong, ie heavy construction.
I'm thinking of using 3/8" okoume ply with a layer or 2 of fiberglass (7 - 10 oz) and epoxy.

A transom mounted trolling motor would provide aux power.

For the outrigger floats, I'm thinking of water ski shapes in the hopes of providing more lift as speed increases. Maybe a stupid thought, but relatively flat shapes would be easier to build. Floats would be out of the water until about 10 degrees of heel occurs.

So what does everyone think? Remember, it's a kinder, gentler forum.

 

This is a situation worth discussing.

1) Cost

You are going to spend the same amount on materials whether you go with a simple form as discussed, or a more complex form that may perform better. If the expense is the same, it is better to end up with better performance, strength and appearance. An ugly, poor performing 10 foot boat will use the same materials and expense as a pretty, well-designed 10 foot boat.

All things considered spend your money wisely, because spend it you will!

2) Time and Effort

Experience teaches how to accomplish the desired quality result in less time. Fabrication efforts can be radically sped up by careful selection of building technique. A traditional plank on frame hull will take very high skills to be accomplished - and will require a fair amount of time as well. A design optimized for simple assembly at a low skill level can attain a very high level of result quality at a fraction of the skill and time required. The more honest you are about your skill level and time available, the better you can gauge and select the building method.

3) Quality Expectations

It is perfectly fine and reasonable to build a simplified flattie panel built boat that meets your needs, but it may not be the prettiest girl on the dance floor. Have a very clear understanding of what your quality expectations are and who you are building the boat for. Expecting a first time homebuild to impress folks on the yacht club balcony may not be easily reached. If you are happy, that is all that is important.

4) Performance Expectations

Having reasonable expectations in this department is critical as well. The more your design deviates from what is known to work, the more potential it may not perform. A four knot scheissboxen that goes upwind may easily outperform your high technology experiment in rig development and foil design. There are very good reasons that hundreds of years of refinement have arrived at today's standards. Experiments often end in failure.

5) Planning versus Execution

Each hour of planning reduces execution time dramatically. I've found that most jobs are 60% preparation, 20% execution and 20% cleanup. Failure to prepare and cleanup increases execution time orders of magnitude.

6) History teaches more than dreaming up new ideas

There are good reasons why most multihulls use narrow outriggers and avoid planing or skimming designs. Find out why and that may help you with your skimming water-ski concept. Given the size and intended use of your concept, you may be better to accept you are talking about a well performing displacement hull, rather than a high performance planing hull. Once you are mentally in the displacement camp, then realizing easily driven hulls are narrow is easier to accept.

Sending a PM to people here may get better results than hoping they respond to a general forum request. Chris Ostlind may be worth talking to.

Simplify, reduce variables and set reasonable goals.

--
Bill

 

Thank you for the comments.
All good points that I will keep in the fore front of my thoughts as I work toward a final design.

One point I would address further is my consideration of water ski type floats.
I realize that a 21 foot, light weight trimaran style boat is susceptible to capsize. My thought was that a low volume float might give more time to react before the event occurs. And since the threat of capsize is greater at higher speeds, I thought that having a float that provided more lift at speed might be a good thing. One other consideration for the float was post capsize handling; the thought being a lower volume float would be easier to manipulate in the water. However, I'm not locked into a float type and will research the float issue more.

Thanks again.

 

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It would be great to see your sketches. I'd like to suggest that you do your sketches in as much detail as possible and then- BEFORE you begin to build-
show them to a naval architect. That will probably wind up saving you a bunch of time and money and help to insure the success of your project and you and your wifes safety.
I know that very small planing amas/buoyancy pods have been used very successfully on boats like Frank Bethwaites HSP's but they are high performance designs. From what I can gather from the information you have provided I don't think a planing ama/buoyancy pod is appropriate for the boat you describe. You might review some of the threads and designs that use beachcat hulls as amas . That will greatly simplify construction and a displacement cat hull with a high Length/beam ratio(skinny) will allow plently of speed as well as providing additional righting moment.
Consider existing,PROVEN, designs along these lines and you may save even more money. Make sure any design you settle on is PROVEN in multiple builds over time or use a reputable naval architect or both.
Look in the multihull threads on boatdesign for concepts that might interest you or, that may inspire you. Good Luck! And keep us informed of how you proceed.
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PS- the Weta tri uses amas with fairly substantial buoyancy. Their righting system consists of flooding one hull and rotating the boat up and then draining the hull. From what I've read it is a viable system that works very well. Just an example to illustrate that an ama with more buoyancy than a planing/low buoyancy ama can be righted.

Weta tri:

 

I would like to ask three questions on how this proposed boat will be used and what its full requirements are.

1.) How fast do you want it to go? Is speed a primary requirement?

2.) Will you be trailering this boat to the water? If so, how big of a tow vehicle do you have?

3.) How much set up time are you willing to put up with? Will the boat be used on lots of short cruises? Or will it be used on longer cruises of a week or more? If you plan longer cruises, longer set up time can be tolerated. If you plan on shorter cruises, long set up time may well doom the boat to infrequent or even non use.

An interesting thing to do would be to list all the boats requirements in descending order of importance.

Doing that will give you a much better idea of what you really need and want.

 

Depending on how much time you have...i'd get an older grp hull...under 24 feet..an old Irwin 23...or a Grampian...or a Hunter 22...something like that...watch craigslist or ebay and get her cheap...then grab a sawz-all , cut out ....and build up to suit...your simply not going to find much under 24' that you are looking for as far as a sweet head and 6'2 headroom...you'll have to improvise and do the work your self most likely...maybe add an aft cabin and cut out the cockpit floor except for the head area...better to have the cabin height towards the stern than some ugly hippo-cabin up front...I dunno your asking alot on a budget...elbow grease is cheap...thats what I am doing anyway with my hunter 20...I cut off the rear of the cabin and the companionway.....am widening the seats by cutting out the coamings around the cockpit...adding an arched hard roof a few inches higher...threw away the pop-top ...all epoxy for the re-fit...$120.00/3 gallons at US Composites....delivery in two days in Florida...I can walk on the roof when I am done and have a bit more head room and with the cabin extension I have room for the person to sit comfortably in the aft seat of the dinette. Two will be able to sleep in the cockpit or at least nap...and I have created watertight compartments from the "berths that ran back under the cockpit...alot of work though...but cheap...I got a little over two grand into this 20-footer.including the boat's $200 price off craigslist and a $260 5hp Tohatsu that has been solid....had her over a year and a half...and she's a bit more than halfway done...they are never "done" thoug.h...after I lay down the roof "skin" I can start sailing her again while I fix the rest over time...i have already sailed her five or six times before I got out the sawz-all including a four day trip 50 miles down the beaches here to Boca Grande and up to 4 miles offshore...and a few trips through the bay to the beach and back...she's gonna be a light coastal cruiser....It's been a lot of fun and some work though...

 

Thanks for the replies Gents.

I will address the comments and questions as best that I can, last to first.

I've considered a smaller keel-boat. There are a couple of Catalina 22s for sale nearby, one even has an outboard with it. For the boat I want, a steel or lead keel of any kind seems like a lot of additional weight that a trimaran style boat avoids, or at least puts to better use. And centerboards take up a lot of space. With that said, I might go look at the 22s again.

Standing headroom is not expected, but a person's height does affect the overall ergonomic requirements though - sitting headspace, hatch and bunk sizes and so on.

My requirements right now are:

1. A head cabin - with a marine toilet or porta-potty. To be determined.
2. Windward performance. My usual boat ramp is in a 90 degree corner with winds often bisecting the angle.
3. Kickup boards. In shallow water most of the time.
4. Speed appropriate for a mono-hull of similar size and displacement.
5. Weight would be around 800 pounds for hull, rig, and outriggers. (Need to nail that down more). Yep, I have the trailer(s) and truck to haul it.
6. Mast would be single-stayed or free-standing.
7. Sloop rigged with self-tending jib.
8. Trolling motor for aux power.
9. Self sufficient for 7 - 10 days.
10. For camp cruising, semi-protected bays (Pensecola/Panama City FL area) and coastal sailing in good weather.
11. Setup time no more than 30 minutes. Outriggers either foldable or plug-n-play.
12. Trailerable and launchable from the average boat ramp.

I've sketched out an outline of the boat.
21' LOD
5 foot max beam at 55% length from bow - say 11'6".
3 foot wide stern.
2 foot freeboard.
1'4" freeboard extra for the cabin area.
box keel draft 12".
plumb bow and stern.

The above specs give a proportional looking hull, no hippo sized cabins.

As stated earlier, the box keel will be sized to carry most of the displacement. In theory, the bottom of the main hull above the box keel would clear (by small amount) the water if tied to the dock in flat water in a loaded condition. I can get the 20" beam needed for fitting a manual marine toilet in the box keel, if the keel starts at least 3' forward of the toilet fitting point, assuming a half-angle entry of 22 degrees or so.

Inspiration for the flat bottom hull comes from an old set of plans for a 16' trimaran, from Popular Mechanics I think. Was a straight forward ply over frames construction. I intend to used tack-n-tape and fiberglass the hull. 3 Bulkheads to reinforce the outrigger attachment points and the mast location.

I guess I should state that I've read all three of Gerr's books, even working through a design using the equations from his Elements of Boat Strength. I've also read Buehler's book and numerous others and what seems like a room full of magazines. Can't even guess at the hours websurfing. And built Bolger's windsprint, making it a sloop-rigged, leeboard sharpie.

To wrap up my essay (anyone still reading?), I'll say the box keel makes the design work for me, giving sitting headroom on a toilet. Which drives the whole exercise. If that really just doesn't work, then I'll drop the idea. The wife will have to stay home, being the one most afflicted. Or I'll have to give up my dreams of coastal cruising until I decide a Mac 26X is affordable. Or find an abandoned Telstar 28.

 

Seems like you're off to a good start, GTO.

I just wonder why you're messing with a trimaran.

The set up time will be daunting unless you go to a folding design and low buoyancy floats.

The low buoyancy floats effectively limit the loads on the crossbeams, as they will go under rather than lever the whole boat out of the water. This way the max loads on them will be the same no matter how much weight is loaded onto the boat.

But it seems that you know what you want.

I, myself, would consider something like Bolger's 'Bird Watcher' design or one of its several knock offs.

There's one in www.duckworksmagazine.com that is only 5.5 by 13.5 ft and only 350 lbs.

 

Mainly to avoid adding weight just for ballast. I see I failed to put "unsinkable" in the list of requirements, but its there. I do envision this as more of a mono with training wheels. I have no plans of competing with REAL tris or cats.

Based upon Doug's earlier comments, I probably will stick with the smaller floats. And now your comment on max loads points out another, very good reason to go with low volume floats. Thanks!

GET OUTTA MY HEAD YOU ALIEN LIFEFORM!!

I have been looking at that very design for the past couple of days!!!



But look at the guy sitting. Flat on the floor, barely has head clearance. I figure since I'm 6'2", there would be negative clearance, not to mention adding a crapper of some kind under my butt!
And that leads to the magic of the box keel. Drop a crapper into the box and with 3'4" of headroom in the cabin I can assume the throne in relative comfort.

I know my preoccupation with said crapper may seem - anal - to some, even silly, but seriously, with my wife's bladder issues and my various gastrointestinal problems, having to head up into the wind, drop the sails, raise a potty curtain and then take care of business may just be a bit too much. I would rather be able to yell, Grab the Tiller!, and jump into the cabin.

Again, thanks for all the comments.

 

My idea was that only the pertinent parts of your anatomy need be concealed.

Your head and even shoulders may well be visible.

I also brought up the 'Bird Watcher' because it is an example of a mono that needs no ballast.

A 'box keel' even just 2 ft wide is going to have considerable displacement and may not sink as deep as you may hope.

20 ft * 2 ft * 0.5 ft * 0.5 = 10 cf = 640 lbs

Also, multis are very sensitive to weight in the ends, especially in the bow, so the commode may have end up in the middle of the boat, fore and aft.

Since Locke Crowther came along, it has been customary to make the main hull of the trimaran very narrow to well above the waterline then widen it with a step on each side for accommodations such as bunks and a galley.