A Wild A** Idea

[Guest Tom Hubbard]

First of all, let me say that I am not afraid to take my lumps, so if anyone thinks that this is the stupidest idea he has ever heard, please feel free to say so. I have had the plans for the Vacationer for over a year now and I pull them out to look at regularly to look at and daydream over. I am wanting to use it as a floating RV that my two sons and I can spend some extended float camping trips on when they are just a bit older. I think the Vacationer is adaptable to this very easily, but the one thing that I have wanted was at least a two battery electrical system and I got to thinking how nice it would be to have all that weight below the hull. I didn't think anymore about it because it was impossible to have the batteries outside the hull. Then I ran across the concept of the box keel and that caused me to think again about the batteries, that if the Vacationer had a box keel, the batteries could go down there where they would also act as 100-200 lbs of ballast. So, what I am proposing is a partial box keel that follows the same basic contours as the full length keelson that is already there. The profile would have to be changed some, but I think it would only be a minor change. The clipper bow would be unchanged, the box keel would swell out from the existing keelson near the forefoot and would taper back to it under the cockpit, so that the box section would be mainly under the cabin and would be filled with batteries and storage or perhaps water ballast. So, am I crazy, a sadist? I am planning to build a model this winter so see just how hard the new keel is to build.

thubbard@indy.rr.com

[Guest Frank Hagan, Weekender, O]

There's a box keel Bolger design that utilizes something like that. You might see if you can find someone with one, and ask them about performance.

If you're into model making, make one of both the original design and one of your modified box keel designs and test them out. It would add some ballast to the boat, which on the Vacationer I think is probably a good idea (the Weekender is small enough that the skipper is the ballast, but I think "live ballast" like this is less effective as the size gets larger).

fshagan@ev1.net

[Guest Tom Hubbard]

Frank, thank for the tip on the Bolger design. Do you know if there is an online gathering place for Bolger fans? I have looked briefly and not seen one. I do like making models, because it is something creative that doesn't cost all that much money. That does bring up a question, does anyone know of a source for inexpensive modeling plywood. I am wanting to use plywood for the model that matches the 1:8 scale I plan to use and the local Hobby Lobby is a lot more expensive than I think I could get the stuff somewhere else.

thubbard@indy.rr.com

[Guest Frank Hagan, Weekender, O]

"Dynamite" Harold Payson has a BBS at http://www.instantboats.com/wwwboard/wwwboard.html where a lot of Bolger people congregate. Payson is the author of "Build the New Instant Boats" and has several Bolger designs in his book (and sells the plans from that website).

There are also a couple of Yahoo groups devoted to Bolger. Go to http://groups.yahoo.com and put "Bolger Boats" in the search box. I got five hits of Bolger related groups, although one looks like a non-boat related site. Anyway, that's a start. I wish I could remember the Bolger design that had the box keel.

fshagan@ev1.net

[Guest Tom Hubbard]

I believe that the design you are thinking about is in "Build the New Instant Boats" or something like that. I will have to stop by B&N later and take a look. I will also take a look at Dynamites site. I had forgotten that he had a website.

thubbard@indy.rr.com

[Guest Frank Hagan, Weekender, O]

I hadn't been to Payson's site in quite a while, and don't think I've seen that BBS before. I'm not a big fan of Bolger's small boats, although I fell in love with a larger sail boat he designed that was featured in Wooden Boat Magazine a while back (high freeboard, more traditional styling, and because of the high freeboard, a fairly open deck plan). And the HMS Rose is certainly a fine looking ship. But most of Bolger's smaller designs leave me wanting.

Still, some of that practicality applied to a Vacationer or Weekender might be appropriate.

fshagan@ev1.net

[normoose]

I like this idea. I made a concrete keel for a 52' ketch rig that was shaped like a double bit axe that drew very little and handled like dream.

I really like this idea. Now where to locate bulk of the ballast, which has to be determined before construction.

Thanx for your post.

Norm

-----------------------------------------------------

"I am an adventurer by fate, not by choice".

Vincent Van Gogh

[Joel]

Tom, Larry Brown, author of one of my favorite books "Frugal Yachting" built an aluminum sailboat called "Bendan the Navigator " . I am pretty sure it had a box keel with batteries in it.

I think its a good idea. Depending on your application I would consider using a number of smaller batteries to maintain the shape of the keel. I think 18AH would be a good size. I like the ones shown in this PDF.

http://www.centricpowergroup.com/DiscoverBattery/PDFFiles/D12180.pdf

joel

[PAR]

The box keel concept is an old one, dating bake to colonial times as a refinement of beach dories, which had their garboard twisted up against the stern post. This was done to permit them to launch from the beach, take to the beach all standing and offer two different displacements (lightly loaded and heavy), but with good handling qualities as both.

Since it's conception, some development has been done, most notably by Billy and later his son John Atkins. A real box keel design has the normal entry and forward sections of a craft, typical of their breed, but around midship a knuckle enters the underwater lines, flattening out the buttocks close to the LWL, but an appendage like, faired "box" twists down and stands near vertical against the stern post. It looks a bit like a "V" bottom skiff that is sitting on top of the back half of a canoe.

In practice the box portion provides the bulk of the light displacement, but the very firm aft sections of the skiff come into play when loaded down or approaching speed length ratios over 1.5 (plane mode). The result is a hull that is easily (economically) driven at displacement speed, semi displacement mode and lower plane speeds. There is a point of diminishing returns when you try to increase the speed length ratio and most box keels have a pronounced "hook" incorporated into the very last station of the aft sections. This helps keep her bow down and the stern from squatting at higher S/L ratios. This hook is also the limiting factor in most cases as it causes a disproportionate increases in drag as the speed goes up.

I don't think Vacationer would take well to this modification without very careful study. It surly will add considerable displacement and generate additional wake disturbance and additional edge vortices. On the other hand it would provide a bilge where the currently isn't one and a handy place for a battery and other equipment stowage. A nice feature, commonly found in box keel boats is a inboard engine, that sits very low in the hull, so the shaft is usually straight out the back of the box.

Currently I'm involved with repairs on an Akins box keel vessel, which is a bill boat, yacht conversion (John Atkins did the conversion) built in 1962. It was John's favorite boat, having logged many miles on her. The benefits of the box keel permit shallow draft and this boat draws only 2' on it's 39' length. The boat can drive to 11 knots on a 50 HP diesel, which is pretty remarkable considering her 11 tons of mass. This amounts to a speed length ratio of almost 2 and very impressive for a heavy carvel fishing boat. I'm also having a rather involved debate on the merits of this hull form on another discussion forum, which is typically geared to the engineers and designers among us, but welcome to all. http://boatdesign.net/forums/showthread.php?t=16066&highlight=box+keel for those that may be interested.

I have a fair amount of understanding of the Vacationer after designing a new keel, rudder and sail plan for an Arizona French door builder that happens to speak and write quite well (couldn't resist, Barnacle). You may be able to entertain a new appendage, but it would be a true appendage, abet a thick one, attached to the underside of the Vacationer. I would recommend a reasonable NACA section and slab sided for construction ease. It will be important to place it properly so your additional displacement is located in spot that will help the boat, not causing her to pitch bow or stern down. Vacationer could use a little additional displacement aft, to keep her from squatting, but precise placement would require a reasonable understanding of the design, concepts and the addition's affects. Structurally, she isn't intended to carry such an addition, so accounts will have to be made to address stress and load transfer too. The under the cabin location would tend to rotate the boat around the center of buoyancy (creating a new one) which would lift the bow and or squat the stern. I think a further aft placement will be necessary. Ideally the appendage should balance the volume equally on either side of the CB, as to not upset trim.

[normoose]

I think that I will have to build the vessel, get some sand bags, and add concrete to the each side of the keel and seal it.

I would usee lead but I don't even use lead sinkers to go fishing anymore. Washers are cheap and you can cast them a long way.

I am inclined to add plate steel or concrete, both of which can take the abuse of beaching anywhere [almost] and provide stability in open water hopping from island to island or from mooring to mooring [an anchor or 2 should do it].

I plan to over build as usual as I am an adventurer by fate, not by choice." V. V. Gogh

Thank you all for the links and advice. I have only joined a few BBS and find that this site has it all thanks to Frank.

[normoose]

I am not saying that I would not use lead if I didn't intend on beaching the vessel often or running aground, thus scraping of the toughest epoxy. Iff I was building a long range cruiser, lead or concrete would be the choice. I would really like to install 3/4" plate steel in the center of the keel during construction, leaving enough wood to attach and to cover the bottom of the keel as well. I do not think that this design calls for a lot of ballast and steel is my first choice, then concrete and finally lead.

We all have are own ideas and i appreciate the input of everyone, even if I don't always agree with with environmental issues by using lead. I am very rough on my boats and use them to the max. I love the idea of being able to beach the boat without anything but the original keel style and size. I believe that I can achieve this by researching and getting the input and experience from others that have built these boats.

I can not wait to see Ray's boat in the soft water, the placement of the ballast and to see it in action.

I believe that I will learn more than most people by using the images that other forum members have sent to me and to see where Ray has placed his ballast.

I have a good idea of where to put my ballast now, without seeing the images or Ray's Weekender but will take all of the advice available.

I really want everyone to know that no advice is wasted on me and all suggestions are thought out and stashed in my mind for future reference.

In the end, the boat that I build will be ready for what I will do with it and to it.

[normoose]

I am attaching an image of the 10' pointed skiff that I built on a rainy Memorial Day weekend in 2000. I deviated from the plans that I found on Payson's web site. It had a scaled drawing of the craft so I bought one of his books out of curiosity. The book is very informative and has many small, tack and tape plans in it. Some, like the skiff have enough information for some to build from.

The skiff called for a 1/4" bottom but I doubled the thickness and you will see why if you look at the attached image of the bottom after shooting the rapids on the local river. I have also found the store that many have been searching for. :wink:

foundit.bmp

[Tom Hubbard]

WOW. Right now I am only lurking here every few months and when I get here today, I find this ancient post of mine suddenly being talked about again.

I am glad that the idea is finding some approval. My life situation has caused me to put my plans for boatbuilding on hold and pursue some other things.

I am still planning to build this boat one day, before too many more years and I still value all the wonderful expertise that can be found here.

Tom.

[normoose]

oh yeah, Tom. i am getting ready to start building a vacationer and won't do it without researching as much as possible as i am hard on my boats and take them where others wouldn't.

I have read every post that I think can help me with my design modifications. Nice to her from you.

Norm...

------------------------------------------------------------

"An adventurer by fate, not by choice."....V. V. Gogh

[Tom Hubbard]

Norm,

I will be following your build. Right now, my family is much more into camping than boating (not Dad's idea, everyone else's). I am currently building a Tiny Travel Trailer of my own design and even SWMBO is happy about it.

Tom