Jim Michalak's Boat Designs
118 E Randall, Lebanon, IL 62254
A page of boat designs and essays.
(1JAN99) This issue will finish the rowing essays with a couple of "how to's". Making a set of oars and a rowing seat/ditty box. Next issue (about 15Jan99) I'd like to update my "materials and tools" essay that comes with my plans sets.
A NEAT WEB SITE....Don Duquet, down in Florida, has a nice web site which features articles from the paper magazine MESSING ABOUT IN BOATS. And there is other stuff there. Click here to read his experience with building and using Toto. A fine tale (but I don't recommend testing a new boat on a windy day). Then poke around the site a while.
Left: DON DUQUET & CO WITH TOTO IN FLORIDA
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MAKING SOME ROWING GEAR
But first, reader Lincoln Ross wrote a letter about my last essay:
"Just read your latest essay on rowing. While I agree with most of what you say, I think that sliding seats may be a little better than you're giving them credit for.
In rough water, those long oars can help you stay upright. I've been out in a recreational shell when it was rough enough to fill the footwell with water, and had no real problems. And the reduced windage is nice. I suppose the tied in feet could be a little tricky if you didn't wear a life vest. Where you do tend to flip is right at the dock. I've been out maybe 50 times and flipped, I think, twice. Both times right at the dock. Once next to a Charles River whitefish (ugh!). If you never let go of the oars you don't go over. Sliding seats let you use your largest muscles, so I think power output would be up for most people. It's a better workout. In a really skinny boat it's the only way to actually work hard.
Lincoln Ross"
Thanks much for the info. I agree especially with the comment that a long skinny fast boat will need a sliding seat to reach its top speed.
MAKING A SET OF OARS....
How long?? That's a tuff one and I avoid it by saying on each set of my plans I show the oars I recommend for the boat. All knowing Phil Bolger said in his first book, "Generally speaking, a good deal less than twice the spread of the locks will serve, and I'd prefer to have oars a little short of the ideal than much too long." I like to use 7 foot oars on good rec rowboats like Roar2 or a light dory that tend to cruise at about 4 mph. Slower boats can use shorter oars. I use 6-1/2' oars on Piccup which will cruise at 3 or 3-1/2 mph even though it has more than 4' between the locks. Short oars work well on larger slower boats too, for example 7' oars are fine for Birdwatcher and AF4. They probably move at about 2-1/2 mph. The idea that the longer the oars the faster you will go is simply not true.
Anyway, I'm going to show drawings for 7' oars which are about the most useful length for me.
WHAT KIND OF OARS....
The oars I make are really derived from the patterns of the late Pete Culler. They are characterized by having heavy square looms inboard of the locks and long narrow blades in the water. An example is shown in Figure 1.
The square looms are easy to build, help balance the oar, help locate the oar in the locks, and keep the oar from rolling around on the wales.
The long narrow blades go against modern thinking of spoons, but for long rowing, long and narrow is the way to go. The average mortal can only pull so much of a load, in spite of what an Olympian might do. The Culler blades can match the mortal's pull. They might slip a bit when starting a heavy boat from a standstill, but once up to speed, the have full grip on the water. They balance better. They are less fatiguing. They have less windage. By the way, the oars of traditional Irish caurrahs have no blades on their oars. Neither do the paddles of some traditional kayaks.
WHAT YOU NEED...
Oars are made from four materials - wood, glue, leathers and varnish.
For wood, I use 1x6 pine boards. The pattern shown in Figure 1 will just barely make an oar from a 1x6. I try to buy a single board long enough to get out both oars. For example, for a pair of 7 foot oars, I buy a board 14 feet long if I can. That way the oars will be a close match on weight, stiffness, and color. I like to use soft wood like pine, it is easy o work and makes a light oar. It need not be clear wood although clear is easier to work Small solid knots are fine and look good too. I've never worried too much about grain because the sticks get laminated and tend to stay straight. But the straighter the grain the better.
For glue I prefer plastic resin "Weldwood" glue and doubt if there is anything better for making oars. Pour some in a cup and squirt in cold water until it has the consistency of normal woodworking glue like "Elmer's. I've found it to be quite true that this glue will not set properly until it is at 70 degrees F for twelve hours like it says on the can.
For leathers I don't use leather. I bind the 8 inches just below the square section of the loom with synthetic mason's twine, about 3/32" diameter. It lasts for years.
For varnish I use ordinary oil based spar varnish.
Now let's talk tools. The tool I use the most in making oars is a bandsaw and I hate to say that because it's not a cheap or small thing that everyone will have. The problem is that you've got to saw a 2-1/4" thick blank. Hand saws will work and the effort should get you in shape for rowing. After all, oars were invented long before the bandsaw. But I see Dave Carnell has built oars using his table saw and Bruce ----- built oars with his sabersaw.
HOW TO BUILD...
first cut the 1x6 boards to the proper length. lay out the centerline with a straight edge. Then draw the pattern for the center piece, the one with the blade., around the centerline. Cut out the center lamination following the line closely with your saw, because the outer laminations of the blank are made from the off fall and there isn't much extra.
You can draw patterns of the outer pieces and cut them out. But it's easier to glue the pieces directly to the center piece and trim them after the glue cures. Trial fit the outer pieces. You may have to trim them for the proper shape where they blend into the blade area of the centerpiece. When you are satisfied, butter them up well with glue, and clamp them in place. You may need to tap in a a light temporary nail to keep the pieces from sliding around on each other because almost all glues are quite slippery until they start to set. Try to get glue squeezed out all around. And be sure the blank is resting straight while curing. Walk away from the blanks until the glue has cured hard.
After cure, trim the outer pieces to match the centerpiece. Use a plane and sander to work these pieces to their final lines, being careful that these faces remain square to the other two unworked faces.
Now cut the two unworked faces of the handle and loom of the oars to their final dimensions. Draw centerlines down the two worked faces and lay out the shape of the handle and loom. Cut to the lines and sand smooth. At this point the cross section of the oar from handle to loom is square.
The oar drawing shows how much of the loom is left square. The rest is to rounded. You start by drawing lines on handle and loom that allow you to make the cross sections octagonal. You can draw them using the gadget shown in Figure 2. Then cut down to the lines with a half round rasp where the lines blend to the square section of the loom. Then use a drawknife or plane to remove the rest of the material down to the lines along the shaft. Now she's eight sided. To round it you're supposed to sixteen side it and then round it out. To tell you the truth, I leave mine eight sided, including the handle and the area which fits in the rowlock.
Lastly you need to trim mass out of the blade. I plane the blade down so its edges are 1/4" thick. Then I use the front roller of my belt sander to hollow the blade slightly on either side of the center, leaving a ridge in the center.
I think the only critical part of these oars strength wise is the 1-1/4" section where the blade meets the loom.
Give the oars a good overall sanding, but leave the handles rough.
Wrap the rowlock area, from the square section down 8 inches toward the blade, with mason's twine. Wrap it tightly and use knots to secure it.
Give the oars three coats of spar varnish. That includes putting varnish on the twine binding. It will go a long way towards holding the binding in place. Don't varnish the handles.
An easy and effective "button" can be made be added to the bound area, to provide a stop which will locate the oar lengthwise in the lock, by wrapping it tightly with three wraps of 1/4" shock cord, and tying the cord with a square knot. If the tension in the cord is right, it will stay firmly in place while rowing and yet allow repositioning up and down the bound area to change rowing leverage when required.
A ROWING SEAT/DITTY BOX....
Figure 3 shows a rowing seat/ditty box that I've been using for years. You might have to tinker with it a bit to get it to fit your butt. As for the height of the box, it is nice for a bar placed across the rowlocks of your boat to cross you at belly button height. That would include any padding on the seat such as a flotation cushion which you should have on board anyway. For that matter a stack of two or three stiff flotation cushions can make a pretty good rowing seat.
NEXT TIME...
I'll review the materials and tools I've used with my own boats.
BATTO
FAST ROWBOAT, 18' X 3', 70 POUNDS EMPTY
Someday I may get to put my full catalog on the net. For now I'll put one design in each issue.
BATTO
Might as well finish the rowing essays with Batto. It's sort of a "retro" boat. Every now and then I go over another designer's older design and try to update it to the way I do boats. I always learn a bit.
Here are the words in the current catalog about Batto:
Batto is a close copy of the Pete Culler clipper bateau Otter which appears in John Burke's book PETE CULLER'S BOATS. Batto is only very slightly different in shape and size from the original Otter and is in no way intended to be a parody of it, only a reworking to the type of construction I prefer. Burke points out that the boat is about as close as you can get to a racing shell with traditional hull, and that it was unforgiving and cranky if improperly used and very elegant and fast if properly used. I would prefer it to be thought of an exercise boat meant for one. Supposedly Culler judged the boat to be safe to handle one third of a person by proposed Coast Guard regulations. I found Burke's book to be very good reading.
The big departure I've made from Culler's work is that I've used "instant" plywood construction, something that Culler didn't like at all. He had a long lifetime of experience with traditional methods and tools and materials by the time he built Otter and Burke says he built her in a one week vacation, with lapstrake sides, cross planked bottom, and all the gingerbread. In the photos it is a true work of functional folk art. Batto won't be in the same league as a work of art, but it should actually be a better boat by almost all other criteria. Built taped seam style with no jigs from 3 sheets of 1/4" plywood, Batto will be a 40 hour project for most any man and will be lighter and faster than the original.
Culler used very long special rowlocks to get the proper oar location in the very low and narrow hull. (You won't be able to stand up in it.) That replaced the need for outriggers which, I can attest to, are a pain for a cartop boat. I think the Culler locks are worth a try, if only because they can be easily removed and replaced. For that matter the boat would take a sliding seat very easily. I'm certain Phil Bolger would quickly point out that locks tilted 45 degrees like these aren't worth a hoot. And he'd say that the hull needs more rocker. But I guess that shows how two very experienced designers can have very different experiences. I know for a fact that the narrow Culler oars work very well although Phil never liked them.
Batto plans are $12 until one gets built and tested.
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. (If you order a catalog from an internet page you might state that in your letter so I can get an idea of how effective this medium is.) 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.
Usually when a design from the Catalog of Prototypes starts getting built and is close to launch I pull it from the catalog and replace it with another prototype. So that boat often goes into limbo until the builder finishes and sends a test report and a photo.
Here are the prototypes abuilding that I know of:
IMB: Click here to visit Tim Webber's page and see some photos of the Texas IMB under construction. Then poke around Tim's web page a bit. I heard this week from the Texas IMB builder who said, "I want to let you know that IMB is alive and looking good. She is now right side up and sitting on her cradle. Soon this boat and carrier will be mounted on the small trailer I have ready......"
Fatcat2: There is an old timer (80 years +) in Minnesota who has completed the hull of a Fatcat2. Fatcat2 is a simple 15' x 6' catboat, gaff rigged and multichined. I think the sail rig will be done this coming winter. Not only has he finished the Fatcat2 hull but he has started a....
Twister. The Twister hull is pretty well cut and fitted, ready to tape. Walt lives north of Green Bay, working in an unheated shed. He tells me there will be no more building until things warm up again next year in late Spring. If you live up there and would like to contact Walt, let me know.
Jonsboat: A builder in Florida has started a stretched version of Jonsboat (16' stretched to 19'). This boat was featured in the 15 April issue.
Herb builds AF3 (archived copy)
Hullforms Download (archived copy)