Jim Michalak's Boat Designs

118 E Randall, Lebanon, IL 62254

A page of boat designs and essays.

(15jul06) This issue will float us down the San Juan River with Chuck and Sandra Leinweber. The 1August issue will rerun the all important sail area math essay.



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....


...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.


Scot Copeland & Co. test fly his new Piragua in California.




Contact info:


Jim Michalak
118 E Randall,
Lebanon, IL 62254

Send $1 for info on 20 boats.



San Juan River Trip

Chuck and Sandra Leinweber who are Duckworksmagazine.com are some of the most avid boaters known. In addition to selling plans and materials and gear to make your own boats they also make their own boats and take them on adventures. In June they took a Toto and a River Runner they had built on a trip out West to float the San Juan River. Chuck wrote:


As you know, we did not make it to the annual Midwest Messabout as we thought we would. What happened is we got an offer to float the San Juan River in southern Utah. This is not something to be taken lightly as there is a lottery to determine who can go. We were invited by Terry Burgess who was awarded a permit for 16 people.

The San Juan River begins in the San Juan Mountains of Southwestern Colorado. It flows south into New Mexico, back up into Colorado very near the four corners, and then into Utah where it ends in Lake Powell which is formed mainly by the Colorado River. The so called lower canyon cuts through Cedar Mesa in a series of entrenched meanders. The most spectacular of these is the “Goosenecks” near Mexican Hat, Utah. Our course would consist of 50 miles of canyon from Mexican Hat to Clay Hills Crossing on a 3000 cfs river traveling at more than 5 mph for most of the way. While described as no more than Class II in difficulty, there were some challenges. One was the sheer weight of gear. The river carries a huge load of silt and filtering water for drinking is not practical, so we had to carry 5 gallons of drinking water per person, making our total load of gear substantial.

Our original intention was to build one of your RiverRunner designs for this trip. We did this and made it strong by glassing inside and out and stitching the chines rather than using the usual chine logs. Additionally, we coated the bottom with graphite mixed with epoxy for enhanced abrasion resistance. Jim Hauer who built the prototype was a great help in building the boat.

Shortly before our departure, we learned that our youngest son, Joe (age 23) would be able to go with us. You may remember that he and a friend built a JonJr several years ago. Anyway, we decided that we would need to take Sandra’s Toto to keep from having to put three people and a week of gear on the one boat.

Within the first quarter mile, one of the plastic canoes capsized and withdrew from the expedition. Our boats took on some water too, but thanks to the watertight compartments in both boats, we never turned over, though we did have some other misadventures. Of six canoes, three capsized during the trip.

The early part of the river was swift with our GPS showing 6+ mph with us just steering. We used paddles for this section and Sandra used her double paddle throughout. We tried rowing facing forward a few times, but it was not comfortable – probably because we were not used to it. Later, when the water slowed near Lake Powell, we found that we got behind the easier to paddle canoes so we rowed facing backwards and were able to easily catch up with the rest of the group. One big plus is that we were able to stand at any time to scout the river ahead or stretch our legs – when they are over half a century old, legs need stretching now and then.

The only real excitement with the RiverRunner came when we hit a rock and Joe fell overboard. I was in the front and upon seeing a rock barely submerged, tried to turn at the last minute. This rotated the boat sideways and we hit the boat on the chine. The impact threw Joe into the water from his perch on the rear deck. To his credit, he held onto his paddle and he was able to easily reboard over the stern.

On that same stretch of river, Sandra completely swamped her Toto yet was able to paddle upright to shore where she bailed it out. You may remember that this boat was build very lightly with ¼ inch ply only on the bottom and 1/8 inch stuff everywhere else. It made for a nice light boat that was easy for Sandra to carry to the water, but not really durable for a river like this. At Ross Rapids, about 2/3 of the way through the canyon, she hit a rock going sideways and punched a hole in the garboard about 18 inches long and 4 inches wide.

I was not too concerned as I had purchased a fresh tube of 3M 5200 before the trip and had brought some tools, screws, and plywood patches. Imagine my concern when the tube of stickum turned out to have set up before it was even opened. Who knows how long it sat on the shelf before I bought it. Sandra suggested Duct Tape but I knew that would not hold to wet wood. Then I thought: why not tape up the hole and screw ply patches over the tape to hold it in place? That is what we did and it worked better than I expected. She did not even have to bail at all for the last 10 miles of the trip. One good thing about building your own boat is you gain the skill to repair it.

At Ross Rapids Joe and I had a little adventure of our own: we hit a barely submerged rock head on. The graphited bottom had already proven itself on some of our Texas rivers so we weren’t worried about gouging, but we weren’t sure what would happen balance-wise when we ran up on a rock at 5 mph. What happened is the boat stopped, spun around and sat there happily providing entertainment for the rest of the group. I used a paddle to pry us off the rock and we immediately ran up on another one. I think we only got really stuck on three rocks total on that part of the river, but we never felt we were in danger of turning over, thanks to the great stability of this boat.
Terry is going to try to get a permit again next year and if he does, we may go again – assuming it does not interfere with the Midwest Messabout. This time we are thinking about building two bullet-proof Totos with glass (which Sandra’s did not have except on the chines) inside and out and graphite on the bottoms and garboards. We would take the RiverRunner again but we cannot agree on who is to be captain so we will want to take two solo boats."

NEXT TIME: We'll review our sail area math.


River Runner


This was a custom project for a man who wanted a Lowe Paddlejon boat but found they were quite rare, essentially a custom order. The idea of a boat like this is to float mild rivers with a guide in the stern directing with a paddle and a passenger or two up front fishing. You might recall the design I did last year called Ozarkian which is very similar, maybe the father or grandfather of the Lowe design. (I suspect southern Missouri is sort of jonboat heaven, the source of most of them both in spirit and in material. I recall driving the interstate down to Springfield, Mo. about ten years ago and near Lebanon, Mo I passed what seemed to be miles of aluminum jonboats and pontoon boats stored in fields along the highway. Even little children there must know how to weld aluminum.)

He sent me some photos of a paddlejon he had seen recently and a sales brochure. I tried to copy the lines, thinking all the time that these boats are a lot more subtle than you might think. At the time I had no real Lowe around to study but the brochure left me with the impression that the paddlejon was perhaps a regular small power jon made long and double ended with swept up lines both fore and aft to allow easier paddling. But it is not quite a true double ender in that the stern transom is raked for the usual 15 degree motor mount. As far as power goes, a boat like this won't plane nicely at all, trying to stand on its stern at the least excuse, so I say 3 hp max.

Getting back to the lines, I had the feeling that these are made from a constant width piece of aluminum, say 32" wide on the bottom and 16" wide for each side for a total panel width of about 64". Stiffening wales are already pressed into the panel. The flat wide panels are folded with a brake such that the proper flare of the sides is established. The end chines are notched and the end bottoms drawn up and the end sides are drawn in to close the notches which are then welded shut. But the chines for the main portion of the hull are not welded at all, just bent. There seems to be another trick in that the top of the sides bends inward a lot sooner than does the bottom of the sides, resulting in a rolling flare that gives the boat a somewhat elegant shape (I think). So you might think a manufactured jonboat is a dumb and brutish thing, but I'm quite certain most of them are actually pretty clever.

Jim Hauer built the prototype in Green Bay and sent these photos. I think it came out exactly as hoped. Remember, this is not really a rowing boat as much as a floating boat so the face forward rowing will be used more to steer than to propel. The photo of the man paddling in the stern shows that the aft transom is still up giving good flow lines there, unlike a square stern power jonboat. Under power Jim said that 2.5 hp is about all you can take, the boat not behaving well above that.

Anyway, River Runner uses five sheets of 1/4" plywood. The idea of the light ply is to keep the boat light enough to manhandle into a truck or onto a car roof but it will take a diligent builder to keep it light. I suspect the aluminum original would be no heavier. Simple nail and glue construction.

River Runner plans are $20 when ordered direct by mail from me.


Prototype News

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.

The out West Picara is I am told done to the point of using it as a powerboat:

The down South Picara is more or less complete now. Should have an updated photo soon.

This long and lean project is a 19' version of Toon2. Shown here on its first sail in very light winds. We will wait a bit longer to get a sailing report in stronger winds.

Here is a Musicbox2 I heard about through the grapevine.

We have a Philsboat going together in California. You can see the interior room in this 15' boat:

And here is another Philsboat in northern Illinois:





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