Jim Michalak's Boat Designs
118 E Randall, Lebanon, IL 62254
A page of boat designs and essays.
(1January 2014) This issue will rerun the old cartopping essay. The 15 January issue will take another whack at the stabiltiy/width study. What has happened that caused the change of plans was that the topic I was hoping to clear up became more muddy the more I studied it. Maybe I'll get it figured out in a couple of weeks.
THE BOOK IS OUT!
BOATBUILDING FOR BEGINNERS (AND BEYOND)is out now, written by me and edited by Garth Battista of Breakaway Books. You might find it at your bookstore. If not check it out at the....
ON LINE CATALOG OF MY PLANS...
...which can now be found at Duckworks Magazine. You order with a shopping cart set up and pay with credit cards or by Paypal. Then Duckworks sends me an email about the order and then I send the plans right from me to you.
Lucille Martin sent this photo of a nice Vireo looking for some water.
If you've got a light boat, cartopping can be a great way to move it around. Your boat is up and out of the way - almost a portable car port. Compared to trailering, cartopping allows more normal maneuvering and parking and freedom from fees and maintenance. I wouldn't consider going on a car vacation without a good rowboat or canoe strapped to the car's roof. The only things carried in the car's trunk are the cushions, PFDs and row locks. The convenience of it all struck home one time when we were leaving for a non-boating weekend. "Where's the boat?" my wife asked. It turns out it's a lot easier to find the car in a shopping mall parking lot with a boat atop!
I grew up in a time when everyone drove Detroit iron. Even family sedans had chassis and drive trains roughly equal to today's half ton trucks. You could stand on the roof, hood, and trunk without buckling anything. Rain gutters and bumpers were bull stout.
Those days are gone forever and it is probably just as well. Those cars got 10 miles to the gallon of gas, wore out a set of tires in 10,000 miles and went to the junk yard before 100,000 miles. New cars weight half as much, get 40 miles to the gallon, and 100,000 miles to a set of tires. But, HEY!, Mr. Designer, what happened to our rain gutters and bumpers.
I'm not certain if any late cars have gutters and bumpers designed for moving boats. Even some new pickups lack them. But there are still lots of suitable good cheap used cars on the market. Ford Escorts up to 1988 had good bumpers and gutters as did all the Plymouth Horizons and Dodge Omnis and I think they made a billion of them. With their short trunks and good gas mileage, these are good cartoppers. If you insist on gold plate, I've noted that some BMW's and Volvo's have excellent gutters. Bolger once suggested that a low flat car like a Lamborghini is ideal (although I noticed he was driving an Escort with roof bars). Also, the man who designed the Yugo was probably much more a boater than a driver, giving it fine bumpers and gutters and not much else.
A very short trunk or a station wagon will make loading easier, too.
You should be able to load your boat easily by yourself. If you can't you should get a trailer. As for weight, a hundred pound hull is the heaviest I care to load. Lighter is better but to tell you the truth, a seventy pounder is about as easy to load as a fifty pounder. So building an ultralight hull to the point of degrading strength or increasing costs can be a marginal decision in my mind.
As far as length goes, it is nice if she doesn't overhang the car's ends very much. The long ones are actually easier to get up to the rooftop but must have their ends tied to the bumpers to be secure. That takes a little time, but, worse yet, many cars don't have suitable bumpers. I think the day has arrived when we'll drill holes in the fenders of our cars to install eyebolts to secure our boats.
But I've found that hulls under about twelve feet long will stay put without bumper lines as will some long slender canoes and kayaks. The short ones are much less affected by wind and turbulence.
As for shape, a springy sheerline is not good for cartopping. Inverted on your roof, the boat's ends will droop down in your view. It's also harder to see when you're loading the hull on the rack. Lift the stern to see what you are doing and the bow dents your roof. It's happened to me.
If you've got a springy sheer and a double ended hull, as in most canoes, you've got troubles. She will have no natural stability inverted. That's great on the water, but having her self right when you've got her halfway to the cartop is a guaranteed dent. My first homemade boat, a Teal skiff, had this problem. Eventually I bored large holes in the stern just under the wales and, after inverting the hull on the ground in preparation for the lift to the roof, passed a stick through the holes. That kept her from getting self righteous while loading. I called it my "flippin' stick" although "anti flippin' stick" would have been better.
Later I built a Bolger dory whose tiny transom was only about 10" wide on top. That's all it took to stabilize her when inverted and I didn't need my flippin' stick. I've learned my lesson and haven't designed any double enders for cartopping.
As for aerodynamics, I've cartopped big dories to little prams and I think they've all degraded the car's performance about the same. Gas mileage on my Escort dropped from the high thirties to the low thirties no matter what was up there. So I'm doubtful about some promised hull or setup having shockingly improved aerodynamics for your cartop. But it could happen.
As for boat details, it's best if there are no lumpy or bumpy things on the wales to interfere with sliding the inverted hull onto the racks. Also on an open rowboat or canoe, 6" cleats mounted inside on the stem and stern will make tying to the bumpers very quick, tight, strong and easy
The roof-to-rack brackets I prefer were purchased years ago at a canoe shop and it says on them "Quick 'n' Easy Industries, Monrovia, Ca". They are bullet proof and attach with clever and foolproof over-center lever latches with no tools. Both racks go on in about a minute.
(I think the Quick 'n' Easy brackets shown are too beefy to fit in the gutter slots of many cars. If you need to, visit a yuppie bike shop for roof racks for gutterless cars. They've got new tech gear but keep in mind they're putting a 20 pound carbon fiber bike on a Porche. Perhaps we'll see the return of suction cup racks. Perhaps we'll be drilling holes in our roof and installing permanent pads with sealant and strong blind rivets. Why not? Try it on your clunker first and tell me how it works.
My cross bars, shown in Figure 1, are from 2x4's although fancy pipe bars are available. Make your bars a foot wider than the boat so you can strap oars and sail rigs up there too. Add blocks to the top ends of your cross bars so your hull won't accidently slip over the ends while loading.
My tie downs are 1/2" lines. You want big stuff here that won't stretch and make them plenty long, too. One end is secured with a loose bowline around the interior section of the cross bar. The free end goes over the boat, under the cross bar and belays on a sturdy 6" cleat which is well fastened to the bar. You can secure the rope very tightly and quickly. My system has no redundancy. If any line or cleat comes loose, the boat comes loose. So everything needs to be solid and secure. The benefit is that there is a minimum of things to attend to.
With the major elements in place it's time to load up. Practice helps a lot. First place the inverted boat next to the hull as in Figure 2, position A. (If it worries you that all this flipping and dragging will scratch your boat, most likely you are correct and will be better off with a well padded trailer.) From position A lift the bow and swing it up to the aft cross bar and rest it in position B. Now lift the stern and push it forward to position C. After a few times you'll get a good feel for where each position is in relation to your car.
Experience will show how far forward the boat should be and you might experiment. I prefer the boat shifted slightly aft of center. Also I find shifting the boat to the right side of the rack reduces buffeting from passing trucks. Don't go to an extreme though, because it's best if the ties pull mostly straight down.
If your boat is too short (or your car too long) to bridge the span from ground to rack in position B, then try the alternate method shown in Figure 3. I use this for short dinghies. Be very careful she doesn't fall off the front crossbar as you swing the stern around.
The hard work is done. You shouldn't have lifted more than 50 pounds at one time.
Securing the boat starts with tying on a 1/4" line to keep her from shifting fore and aft on the rack. I cartopped for years without this line, relying on friction alone to the job. But when friction gives out things get exciting. Once, while exiting the interstate in Birmingham, Alabama, at night, my dory slid forward on the rack a foot or more and every line up there went slack. Luckily I was coming to a stop anyway and retied the boat. But when that happens while you are being passed by a convoy of semis in a crosswind, you'll get some new grey hairs. The fore and aft line cures that problem completely. I usually tie it through an oar socket but it could also be permanently attached about anywhere in the center of the boat. Pull tight on one end and belay on the cleat on the front crossbar. Pull the other end tight to the aft bar and cleat there. Now your boat is secure fore and aft.
Pass the large 1/2" lines over the hull, pull tight, and belay to the cleats right over the fore and aft line. Now she can't go up, down, or sideways either. For a boat about 12 feet long or less this is all you need. Skinny low canoes a bit longer than that will be OK too.
The whole process from flipping the boat to drive away takes less than five minutes.
If you have a longer boat you should really secure the ends, at least the bow, to the bumpers to keep it pulled down and centered. The best way is to have 6" cleats screwed to the bow and stern with long lines tied permanently to them. Pass each line around a bumper support on one side and pull tight, then around the other support, back to the cleat on the boat, pull tight and belay. The line forms a triangle from bow to bumper corners and back to the bow. She can't go up or sideways.
Oars and sailing spars can go up there too, secured instantly with bungee cords.
Here's a major suggestion: Once you've mastered the solo loading process, don't accept help no matter how well intentioned. You may get some new roof dents or, worse yet, be distracted from some important tiedowns. Your "help" needs to be well educated in your system first.
The beauty of cartopping is that now you can drive around as you normally would. Well, almost. I should warn you about two things.
First is high winds. Once I drove the beautiful hills of Western Kentucky on a sparkling autumn day with my 16 foot dory atop a 1.6 liter car, pushing straight into a 30 mph wind. Full throttle gave me about 55 mph on the flat, of which there ain't none in Western Kentucky. Driving straight into high winds is primarily an inconvenience but high crosswinds can be dangerous. I almost lost that dory, and maybe the car, over the side of the Pensacola Bay Bridge in a crosswind. High crosswinds can always make for spooky handling, especially when the boat on the roof is almost as big as the car.
The second warning involves turbulence near large trucks. Car transporters seem the worst. Never stay in the turbulence near a truck on the highway. Your boat will start dancing around on the rack and add jerking loads to your rack. Either pass that truck or drop back clear of his wake.
If a truck approaches you at speed in the opposite lane of a two lane road, get as far to the right as possible. His bow wave will pass quickly but can give you a good jolt. The wave seems to attenuate rapidly with distance and a few extra feet of spacing on him will make a difference. That's why I suggest loading a hull on the right hand side of the rack.
The combination of the truck wake in a crosswind is the worst case.
OLIVEOYL, Cabin Sailboat, 15' X 6', 500 pounds empty
OliveOyl was designed for someone who likeD AF3 but wanted more cabin room and comfort, but not more length. So I actually had some AF4breve drawings handy when I drew the lines for the new boat. Although Olive is the same length as AF3 the cabin is deeper and the bottom a foot wider. One thing the owner did not want, which made the larger cabin possible, was a large cockpit. So I've drawn a bridge deck which extends into the cockpit, reducing foot space there, and also just borrowed length from the cockpit and put it in the cabin. So the floor length in the cabin is over 8'long but you will probably sleep with your feet stuck under the bridge deck. I suppose the downside is that the cockpit is less than 5' long so two adults would fill it. I am guessing an empty weight of 500 pounds but it will take 2000 pounds to put its stem in the water so she should take a fair load.
I suppose I've learned a bit since I drew AF3 a while back. One thing I've learned is that when beached a boat like this is much easier to board if the bow is not too high, thus on this boat I've cut down the bow enough so you can sit on it anD swing your legs around right into the cabin entry in the bulkhead, I hope. The owner did not care about that and I don't think she beaches much in her area.
Now, the owner wanted a conventional cabin with sliding hatches so I drew that. And with it went a mast mounted on a tabernacle. I drew the mast off center as I normally do, attaching it to one of the main cabin deck beams. That moves it out of the center of the boat where you will be sleeping. But this boat could be simpler if it had my usual open slot top with a one piece mast. Such a layout would be a lot better I think for a boat which would be sailed off a beach too since it would allow the skipper to hop on the bow after pushing off, and then run upright back to the cockpit. As is he would have to creep down and tHrough the cabin or go over the cabin but I should warn you that, with AF3 at least, standing on the cabin top is an invitation for capsize. After all, these are not large boats.
The rig shown is pretty much right out of the AF3 experience, in particular with AF3's balanced lug rig. The spars are short and cheap and the mast short enough that the tabernacle won't be required if the open slot top is used.
But I doubt if OliveOyl would stay with an AF3 in a race. She has the same rig but she is wider, deeper and heavier and bound to be slower. On the other hand she is a much better overnighter since the AF3 has a minimal cabin suited for a backpacker.
In a lot of ways I think OliveOyl is more of a shortened Normsboat and if you don't mind the extra length and the weight and cost that go with the extra length, Normsboat would be I think a lot more boat for the buck.
Conventional nail and glue construction. She needs seven sheets of 1/4" plywood, two sheets of 3/8" ply, and four sheets of 1/2" ply.
Prototype plans for OliveOyl are $35.
Some of you may know that in addition to the one buck catalog which now contains 20 "done" boats, I offer another catalog of 20 unbuilt prototypes. The buck catalog has on its last page a list and brief description of the boats currently in the Catalog of Prototypes. That catalog also contains some articles that I wrote for Messing About In Boats and Boatbuilder magazines. The Catalog of Prototypes costs $3. The both together amount to 50 pages for $4, an offer you may have seen in Woodenboat ads. Payment must be in US funds. The banks here won't accept anything else. (I've got a little stash of foreign currency that I can admire but not spend.) I'm way too small for credit cards.
I think David Hahn's Out West Picara is the winner of the Picara race. Shown here on its first sail except there was no wind. Hopefully more later. (Not sure if a polytarp sail is suitable for a boat this heavy.
Here is a Musicbox2 out West.
This is Ted Arkey's Jukebox2 down in Sydney. Shown with the "ketchooner" rig, featuring his own polytarp sails, that is shown on the plans. Should have a sailing report soon.
And the Vole in New York is Garth Battista's of www.breakawaybooks.com, printer of my book and Max's old outboard book and many other fine sports books. Beautiful job! Garth is using a small lug rig for sail, not the sharpie sprit sail shown on the plans, so I will continue to carry the design as a prototype boat. But he has used it extensively on his Bahamas trip towed behind his Cormorant. Sort of like having a compact car towed behind an RV.
And a Deansbox seen in Texas:
Another prototype Twister is well along:
And the first D'arcy Bryn is taped and bottom painted. You can follow the builder's progress at http://moffitt1.wordpress.com/ ....
AN INDEX OF PAST ISSUES
THE WAY BACK ISSUES RETURN!
MANY THANKS TO CANADIAN READER GAETAN JETTE WHO NOT ONLY SAVED THEM FROM THE 1997 BEGINNING BUT ALSO PUT TOGETHER AN EXCELLENT INDEX PAGE TO SORT THEM OUT....
THE WAY BACK ISSUES
15jan13, Drawing Boats 1, HC Skiff
1feb13, Drawing Boats 2, Shanteuse
15feb13, Drawing Boats 3, IMB
1mar13, Figuring Displacement, Paddleplank
15mar13, Drawing Boats 4, Frolic2
1apr13, Drawing Boats 5, RiverRunner
15apr13, Drawing Boats 6, Picara
1may13, Two Letters About Keels, Blobster
15may13, Drawing Boats 7, Roar2
1jun13, Drawing Boats 8, Polepunt
15jun13, Rend Lake 2013, Toto
1jul13, Drawing Boats 9, AF4 Grande
15jul13, Taped Seams, Mikesboat
1aug13, Plywood Butt Joints, Paulsboat
15aug13, Sink Weights, Cormorant
1sep13, Lugsail Rigging, Hapscut
15sep13, Sharpie Spritsail Rigging, Philsboat
1oct13, Modifying Boats 1, Larsboat
15oct13, Modifying Boats 2, Jonsboat
1nov13, Modifying Boats 3, Piccup Pram
15nov13, Sail Area Math, Caprice
1dec13, Stretched Stability, Ladybug
15dec13, Trailering, Sportdory
Mother of All Boat Links
The Boatbuilding Community
Kilburn's Power Skiff
Bruce Builds Roar
Rich builds AF2
JB Builds AF4
JB Builds Sportdory
Puddle Duck Website
Brian builds Roar2
Herb builds AF3
Herb builds RB42
Barry Builds Toto
Table of Contents