Ben Scobbie in Piragua
Contents:
Contact info:
Jim Michalak
118 E Randall,
Lebanon, IL 62254Send $1 for info on 20 boats.
Jim Michalak's Boat Designs
118 E Randall, Lebanon, IL 62254
A page of boat designs and essays.
(15Jan00) This issue reviews some Piccup Pram spinoffs. Next issue, 1Feb00, will present some ideas about hollow spars.
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Ben Scobbie in Piragua |
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PICCUP SPINOFFS
PICCUP SQUARED...
Piccup Pram was my first design to get built. Here is a photo of it about ten years ago at Big Lagoon near Pensacola, Florida:
She is shown with the original 55 square foot rig. I still have the boat. The sail rig has been experimented with many times but the hull is identical today as then, except for color. You can see the big bow transom, the sweeping sheer and the multichine section. She's 4' wide and 11' long, wide and short and she sails so well because of those multichines I think. The size was quite right, easy to slide into the back of my pickup truck, which was the original idea behind the boat. And at 90 pounds light enough to cartop on an economy car. In the center is a 6-1/2' long cockpit which will hold two adults and sleep one on its 2' wide flat bottom plank. At each end are buoyancy/storage chambers, about 6 cubic feet each as I recall, plenty to keep a swamped cockpit floating very high although Piccup never capsized on me except on purpose.
After a couple of years with Piccup I got to wondering how much the boat's success was due to the multichines. I dreamed up a flattie version of it, the same overall length and layout, but with a 3' wide bottom plank with hard chines in lieu of the multichines. I called it Piccup Squared. Here are the lines:
I gave the boat a small amount of flare which allowed a good spread of the oar locks while maintaining the 3' bottom width. I thought the 3' bottom width was about the most I could use and expect any sort of handling in rough water. It was the bottom width of my old Bolger Teal and I was familiar with it. Also in the best Bolger theory I gave the sides and bottom the same curvature, a feature which is supposed to provide the least turbulence at the hard chine. I swept the bow well up to clear waves, but the stern was kept a bit low such that the transom would just meet the waterline with two adults. That feature also resulted in a fairly wide stern. The extra stern volume was supposed to give the boat a chance at using a motor.
I built the boat in my usual cheap way. I used lauan underlayment for the sides and fir exterior plywood for the bottom. It was a nail and glue job all the way with lumberyard stuff with external chine logs as you might notice in the line drawings. I had a bunch of old paint around and dressed it up in a camouflage paint scheme, a feature I copied in later boats. (The funny thing about the camo paint job is that sportsmen like fishermen and duck hunters took to the boat immediately even though I was sailing it, unlike a white boat which is apparently a yacht paint scheme.) I found that the boat blended in with surroundings much better as I went beachcombing or bushwacking or shore camping. And from a practical standpoint it's the easiest sort of paint scheme to apply and touch up since nothing is supposed to match or be smooth and shiney. I varnished the interior with no sanding between coats so the interior has a dull natural wood finish. No slipping on the bottom and doesn't show dirt or mud. Since it is best left rough for footing, refinishing the inside bottom is a breeze - just sweep out the big chunks and add another coat or two of varnish. I'll add that varnishing a natural wood boat all over might be the very best camouflage scheme.)
By the time I'd built Piccup Squared I was already thinking Piccup could stand more sail area and Piccup Squared quickly became a test bed. My first polytarp sail was tried on it as shown below. This sail has 74 square feet of area and is to the Woobo sail plan. This sail was made exactly as a Dacron sail would be made. I cut the tarp into 3' wide strips and sewed it up with normal broadseams.
Looking at this great photo reminds me of how it came to pass. Karl James had called me saying he was thinking about making my Jewelbox design but was unsure about the lug sail rig. He was returning to Texas from Woodenboat School and stopped by Rend Lake for a sail in Piccup Squared with a lug rig. That's Karl at the helm. Karl went on to build the Jewelbox and went on to many adventures with it. (Jewelbox has a new owner now in Florida somewhere. Karl replaced it with his own design, sort of a blend of Bolger's Black Skimmer and Martha Jane but he's stuck with the balanced lug rig.)
In the photo you can see the wind is quite light but the boat is moving well under that big sail. She is heeled a bit and Piccup Squared is in her element. Under these conditions she is probably as fast and as good as the original Piccup. Many folks would think she is more comfortable because of her wider bottom. The heeling is pretty important to a flattie and I think the trick to sailing one is to keep the heel just right with the windward chine barely out of the water. In really light winds you might sit on the "wrong" side of the boat to keep that chine out. Piccup is different - sail it flat whenever you can. In high winds you need to tend the sail so the heel is just right. I never capsized Piccup Squared except on purpose. The sides were low enough that I'm pretty sure she will take water over the side before capsizing, unlike higher sided flatties, and I feel that is a good feature in that you get a small wet warning instead of a big wet surprize. The original Piccup really is better in rough water but you would expect that.
Here was another test sail on Piccup Squared. Jim Huxford was at the helm here. The green sail was my second polytarp sail. This one was made in one piece though, no cutting the tarp in strips and sewing it back together. "Darts" were sewn in four places where a Dacron sail would have variable seam widths. This sail was also the first 68 square footer, the sail I advise everyone to use on the Piccup family. The yard and boom are the same length as with the original 55 square footer, but the hoist is 2' taller. When reefed this sail returns to 55 square feet.
Looking back at this photo I'm reminded of the troubles I had with stretching of the luff. A balanced lug sail will set closer to the wind if there is a lot of tension in the halyard, as will almost any sail. But the stretchy polytarp had trouble in the highly stressed luff. It didn't tear, but it would stretch a lot of the draft out of the front of the sail. The result was the front of the sail was very flat and the draft was mostly in the aft half of the sail - not the ideal. This sail luff was later stiffened with a couple of fiberglass tapes which helped a lot.
TWIXT...
After a couple more years I wondered if Piccup Squared could be improved with a V entry in her bow. By this time I had a season or two with WeeVee and knew it sliced and hopped over waves instead of pounding over them. But the deep V middle was very uncomfortable especially while sailing, and she was too tippy for the general public. Could I combine the deep V entry with Piccup Squared's flat bottom? By this time I had figured out how to do twisted panel expansions, too.
Here is what I had in mind, shown here as the lines of the 8' dink Tween.
To make a bottom like this the idea is to slit a single panel up in the bow and twist the two sides into position and tape over the slit. The aft part of the boat is one piece flat bottom. This sort of construction is something I had seen in my youth, and I kept all those old magazines like Science And Mechanics which had a boat article in every issue. William Jackson, another midwesterner, was the creator of many of them.
Rather than build a new hull to test the idea I chopped the forward bottom off Piccup Squared and converted it to Twixt. Here is Twixt on shore. You can make out the point of the deep V bow and see she still sits very upright on her flat middle.
The constrution of the mod was a bit interesting - taped seams for the first 5' or so and external chine logs for the rest. But it worked.
How did she go?? It was a success to me. Not as smooth as Piccup but smoother than Piccup Squared. She was indeed twixt! One thing I remember about sailing the rebuild was that at speed the bow shot water out to the side where the original Piccup Squared always went up and over the water.
That Twixt photo also shows another episode in polytarp sail evolution. This one had the fiberglass tape on the luff as you see. But it also had darts on the luff to simulate a crosscut sail where my previous ones were seamed to simulate a vertical cut sail. The idea was to increase the draft towards the front of the sail. It was quite a success and you can see that this sail has a lot more draft than the green one. This grey sail was about as good as anything I have tried or could expect from my own sailmaking. It had one problem - I didn't keep track of what I had done and had no idea how to reproduce it much less describe it to someone else. I kept it until I came up with the radial dart system I use now and which I've described in detail on this web site. The new method is just as good and I know how to change the pattern shape to get just the results I want. Also in the photo I notice that I had learned that these sails go better if the yard crosses the mast about 40% aft from the throat.
TESTS WITH MOTORS...
You might remember that the stern lines of these boats were kept full with the idea of maybe using a motor. Piccup Squared was tried with a small Minnkota and Twixt was tried with an old Sears 7.5.
The Minnkota clamped straight to the stern locker opening. These motors are actually meant to be clamped to the side of a hull and have a lock to keep them in position. When clamped to the stern I found I could get the motor to swing up if it hit anything by holding the locking pin down with a wire. Normal thrust kept it down otherwise.
Even with the wide and deep lines aft, these little boats can't take a lot of weight in the stern. The motor weight is probably acceptable, but the weight of the battery makes it worse, and the weight of the skipper back there makes it impossible. I warn folks several times a week about this but I still see motor plates on fine sterned rowing boats. That doesn't bother me like it used to since I've positioned myself to get an "I told you so!" and since I'm pretty sure no one will try a motor like that more than once.
But the electric conversion was eventually quite a success. Here is what I did:
The motor was not modified except to disable the locking pin and to clamp a wooden tiller arm to the shaft. The tiller stick was an old cane pole with twist together ferrules (a "found' cane pole, the best kind). The connection of tiller arm to tiller stick had to be a universal joint of sorts. I loosely lashed the two together and wrapped it over with some light shock cord, the stuff used to lash tent poles together. The tiller stick ran forward into the cockpit and I could steer the boat from anywhere up there. I sat facing forward in the center of the boat. The battery was right behind me, so the major weights of the system, me and the battery, were in the middle of the boat and she trimmed level. I was unable to reach the motor speed controls easily but that was not a problem. I set the speed handle to something appropriate and ran the cables with clamp ends forward to the battery which was right behind the seat. I could reach back and connect them easily when ready to go. To maneuver at slower speeds near a dock or obstacle I simply pulsed the motor by connecting/disconnecting one of the battery leads.
It worked very very well and I would suggest this method for any small boat that was not designed to really use a motor, that is for a boat without a deep wide square stern. She would go a bit faster than rowing speed under full control. I thought once she would go faster with more pitch to the prop since these trolling motors are intended to hold a heavy boat nearly still in a wind, and not to push a light boat quickly. I bought another plastic prop and found that by heating it in the toaster oven when my wife was not around I could reset the pitch of the blades. I tried it once but I gave up on it when I realized that I was only resetting the tip pitch.
One eye opener with the electric set up was that you need a very large battery to really go anywhere. Don't bother with a small car sized battery. You need a real trolling battery and they will weigh 70 pounds or more. (I know you are going to try a car battery but I've just positioned myself for another "I told you so!") A 10 horse Johnson weighs less than a trolling motor battery. And a pound of gasoline has 30 times the energy as a pound of storage battery.
Twixt with the gas motor was never really a success. There was no way to keep the weight towards the middle of the boat although Idid use a short tiller extension made of PVC pipe. I recall making only one full speed run carefully under totally calm condions, my weight as far forward as possible and everything loose in the boat stuffed up in the front of the bow locker. Boy did that bow point to the sky when I opened it up! I could hardly see over the bow even though it was only 7' in front of me! My records show it went about 9 knots at full throttle, consistant with about 5 hp, which is believable for a 25 year old air cooled motor that has "7.5" stamped on it. It might work with maybe 2 hp and be useful and sane. I think it would go 6 mph or so, a lot faster than while sailing or rowing. Better yet is to build a Jon Jr. which is the same size and style but with a flat run aft.
LAST THOUGHTS...
I don't know if the experiments proved anything that wasn't already known. The more complex Piccup was better all around but the simpler Piccup Squared was about as good with smooth water. And Twixt was 'twixt.
I used the Twixt shape in a couple of other designs that were built. The little dink Tween was a success, the builder saying it easily cut the motorboat chop at his lake. And the shape found its way into the 24' Petesboat. Pete James told me the V entry was a wasted effort on the bigger boat which is a planing motorsailer and spends a lot of its time with that V entry totally out of the water while planing. So I'm left with the idea that the V entry is more and more important as the boat gets smaller and smaller!
Plans for Piccup Squared and Twixt didn't sell well and I took them out of my catalog. But I still have them around for $20 a set if you are interested.
NEXT TIME...
I'll present some ideas about hollow spars.
PIRAGUA
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PIRAGUA, SWAMPBOAT, 13' X 30", 70 POUNDS EMPTY
Piragua is a very simple useful boat. I probably get more Piragua photos than of any other boat, an indication that more Piraguas get built. Piragua is made from two sheets of 1/4" plywood with very simple old fashioned glue and nail construction. It's very suitable as a first project, both as a way to learn construction and as a boat you will use a lot. But the first Piragua almost never got built, an indication that you can't tell what will be popular in this hobby. I drew it up an thought it pretty good for what it was supposed to be. I put it in my prototypes catalog and had two blueprint sets printed. After a year in the catalog I still had those two prints! I took it out of the catalog. About a month later I sold one set to Don O'Hearn and gave the other set away to Bob Waters who had ordered Toto plans, saying he was looking for a project for his sixth grade shop class.
Both boats got built! Waters' bunch of kids finished the first one, shown below. Bob also sent an article from his local newspaper showing the boat with himself and a class full of smiling kids behind the boat. I still have the copy on my wall and always thought it to be a trophy!
O'Hearn's boat followed very closely and he lives close enough that he brought the boat to our Messabout and I had a chance to try it myself. I thought it was quite good. I could just barely stand up in it, very common of this sort of narrow boat. It's 24" wide on the bottom and I've found that you can't reliably stand up in something that narrow. Don used the boat for fishing in little waters and keeps his butt on the seat. You paddle Piragua with a double paddle like a kayak. Here is Don's boat with his son at the paddle.
Here is another photo of Bob Taylor's boat. His boat has crowned decks with access via large deck plates in the bulkheads (the blueprint shows flat decks with hatch openings on top).
Steve Jacob built this one with Spanish moss hanging above. His used taped seams instead of the external chine logs with some crown to the decks.
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And here are some photos from New South Wales from Ashley Cook. I'm very glad these boats are getting around. You can see these are best as solo boats but have the room and capacity to take some passengers in good conditions. Also you can tell that kids really take well to this sort of boat. They are easily understood in one glance. Still, you have to take any boat seriously. If you fall out of or capsize a boat like this you well need special training and gear to get going again in deep water. If built with the end air boxes the boat will have plenty of buoyancy but probably won't be stable enough for you to get back in. I think the only way to do the job is with a bailing scoop and a way to lash the paddle across the boat with a flotation cushion attached to one end to stabilize the boat in roll. You have to do all this as you swim around. My own appoach is to use these close to shore in warm water!
Plans for Piragua are still $15.
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.
Here are the prototypes abuilding that I know of:
Jonsboat: Greg Rinaca near Houston sent this photo of his completed Jonsboat, land bound until he rounds up a motor.
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Mayfly12: A Mayfly12 is going together up in Minnesota. The decks are on and he's into the sailing bits. By the way, the sailing bits on almost any sailboat large or small consume about half of the effort in labor and materials. Just when you thought you were about finished! (Just talked to the builder and the project is on hold until next spring while he moves into his new house.)
AF4B: A builder in Virginia is building AF4Breve, a 15.5' version of the 18' AF4. I tried to talk him into building the 18' version but he had two very good reasons to go shorter - a short trailer on hand and insufficient building space for the larger boat. The AF4B is essentially a "scrunched" version of AF4 but comes from a whole new set of drawings. The prototype is in the final building stages where the sanding and filling and painting seem endless. (Just heard anew from the builder. Seems his property and priorities have been temporarily rearranged by Hurricane Floyd. So progress on AF4B is now on hold.)
AF2: Richard Spelling has his AF2 about ready to launch and you might be able to see it sail at Rich's site. Here he is trailer sailing as we do in the midwest during the winter:
Herb builds AF3 (archived copy)
Hullforms Download (archived copy)
Plyboats Demo Download (archived copy)
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