PolySail International

High Performance/Low Cost Sails for Small Sailboats

 

 

 

Building the Z-PDR (Racing Version of the PDRacer)

 

Ryan Gray pilots the Z-PDR back to shore after her first test run. Note the angle of the kick-up

leeboard  as he powers into the sandy shore of the Intercoastal Waterway near Port St. Lucie, Florida.

 

Most early Puddle Duck Racers, or PDR’s as they are known, had a fairly boxy profile based on the basic hull requirements drawn up by David “Shorty” Routh, the ceator of this US Sailing certified racing class. Routh’s class requirements were fairly simple for this 4’ x 8’ scow assuring that the bottom 10” of these boats would have the same defined hull shape. (See the class rules at http://pdracer.com/ ) Above the 10” defined hull section, however, the individual PDR builder/designer had free reign. The creativity of design this “open” concept allows has made the PDRacer one of the fastest growing small boat classes in the world.

 

Our first PDR Hull #100 Lame Duck was typical of these early PDR’s. Below is a photo that shows Lame Duck in the foreground and two of four other PDR’s that I helped others to build.

 

The 2008 Lake Vista/Hoosier Regatta. “Lame Duck” is the boat in the foreground.

Five PDRs participated in the race. All had their hulls built in my workshop.

 

Although some of these boats carried different sails, most of the hulls were substantially alike on the exterior. Freeboard was about 15 ½” to 16”, bottoms were ¼” 5-ply underlayment nailed to cedar chines cut to the rocker of the bottom, and leeboards and rudders were made to kick up for sailing in Indiana’s shallow lakes. One major difference was in the sail plans. While Lame Duck and another boat carried the 60 sq. ft. Bolger leg’ o’ mutton sail, two other boats carried a 75 sq. ft. lateen and a 55 sq. ft. balanced lug sail according to the owners’ preferences. The building plan and instructions for Lame Duck are outlined in an article I wrote earlier called Camp Sailboat which is posted on my web site at: http://www.polysail.com/Camp%20Sailboat.htm

 

One change that we began to incorporate after Lame Duck was building the sides with the frames already attached rather than building the entire framework and then attaching the sides. A second innovation that I tried on Tom Heiser’s  #223 Amakusa Duck was to construct the Styrofoam flotation as a single removable unit supporting a one-piece deck instead of just filling in the side frames with foam and adding 2” of extra flotation around the inside of the boat. The initial flotation unit was built from a single 4’ x 8’ sheet of 2” thick Styrofoam. The basic premise behind the insert was that with the foam placed up under the deck, there would be more flotation in that area, and if the boat were knocked down, the boat would float higher and little to no water would be shipped over the decks. The foam insert concept was carried over to the Z-PDR, and subsequent flotation tests validated that theory. The plans and pictures for that Styrofoam insert for Tom’s boat are shown below. For the Z-PDR the insert height was cut down to 11.75 inches and curved to fit the shape of the sides and bottom. Consequently, the shaped Styrofoam provided even more support for the decks on the Z-PDR.

 

 

 

The last two photos show the completed Syrofoam insert alongside the nearly completed hull.

 

 

 

 

 

 

 

Tom Heiser of Muncie, Indiana, sails his lateen-rigged Amakusa Duck in the 2008 Hoosier Regatta. Tom’s hull was the first to have a one-piece Styrofoam insert under the decks.

 

Wild Duck, hull # 143, was constructed in an attempt to establish a new PDR world record for the amount of sail carried. At the same time, I wanted Wild Duck to carry a rig that would allow her to be sailed wing on wing downwind for more speed. While the hull was similar to other PDRs I had built, the bow featured a deck and mast steps to support up to three masts and sails.

 

I first sailed Wild Duck at the 2007 Midwest Messabout hosted by Jim Michalak at Rend Lake, Illinois. Under her twin 52 sq. ft. Leg O’ Mutton sails, she proved very speedy in light winds. The 104 sq. ft. biplane rig also proved responsive in nearly all points of sail with the one sail blanketing the other only when sailed at right angles to the apparent wind.

 

I tested Wild Duck with various sail combinations and found that, with her port-side-mounted leeboard, she was most easily controlled with a single sail up in either the port or center mast position. With a single sail up on the starboard side, the helm was unpredictable. In 2008, I combined her 104 sq. ft. biplane rig with a 60 sq. ft. leg o’ mutton sail to set a world record for the amount of sail carried on a PDR.

 

 

 

 

 

 

Testing Wild Duck’s biplane rig

This photo taken at Rend Lake by Jim Michalak is featured in the PolySail International slogan “Buy low; live slow; sail fast!”

Wild Duck setting a PDR world record of 164 sq. ft. of sail carried.

I considered setting the Z-PDR up for a biplane rig as well, but I was afraid that with only about 6” of mast bury, she could not support two large sails. However, the large sail concept was not abandoned for the Z-PDR. Besides her 58 sq. ft. sailboard-type sail that she carried on her first test, the Z-PDR can hoist a 100 sq. ft. balanced lug or an 85 sq. ft. leg o’ mutton sail on her extendable aluminum and bamboo mast.

 

During the winter of 2007-2008, after discussing participating in the Texas 200 with John Nystrom of Peru, IN who sails hull # 134 John Duck, I began construction of yet another PDR. The concept  drawings showed a cabin approach, but this was later changed as it became clear that my community college teaching schedule would not allow me to participate in the five-day, 200 mile Texas event. The boat that emerged did have some unique features, however, including:

·         An all Styrofoam, fiberglass covered bottom;

·         A roll-up cuddy cabin made from polytarp and sail window material;

·         Add-on exterior Styrofoam panels to make the boat class legal.

This last add-on feature led my 6 year-old grandson to dub Webfoot hull # 199 the “Transformer Boat”, after his favorite movie at that time.

Webfoot concept

Initial drawing and cardboard mockup

Bottom, showing extensions for mounting sides to make the boat class legal

Webfoot goes 3-D. Assigned hull # 199. Note add-on sides

Interior completed. Weight 54 lbs.

Webfoot awaits float tests on Lake Vista

Canopy extended

Wind pushes the lightweight Webfoot along at a comfortable pace. Canopy acts like a small spinnaker downwind.

This is the only picture I could find of Webfoot under sail with her sides on. The sail shown here was only 34 sq. ft. but pushed the boat along nicely.

 

Webfoot was completed early in the summer of 2008 just in time for the first Hoosier Regatta. However, no one was available to sail her in the race itself. She was sold in the fall of 2008 shortly before we moved to Florida.

 

With Webfoot I began pushing the envelope on light weight hulls and cabin structure. I had used the Styrofoam bottom previously in a 4’ x 8’ scow that was one of five boats in the Hot Tub series I had built. (See this account at http://www.polysail.com/boatnote.htm ) Boats of this size with a 2” Styrofoam bottom float high even when loaded and will continue to float even with a substantial hole in the bottom. However, the bottoms are easily damaged and are not easily shaped to the extreme stern rocker of the PDRacer. The flat run of the Hot Tub scows, on the other hand, are more suited for the lightweight foam bottoms. Although Webfoot’s hull was lightweight, the aluminum mast and wood kickup rudder and leeboard added considerable weight to the structure. All would need to be redesigned for the Z-PDR.

 

In designing Webfoot’s canopy/cabin, I was faced with the question of how to support the structure without much weight. I solved that problem by incorporating two mahogany lathe arches on either side of the boat. These arches, in turn, supported two crosspieces and the polytarp canopy. Each arch was made up of two 3/16” thick x 2” wide lathing strips that were glued together while arched. The resulting arches were incredibly strong for their weight and would support the entire hull when turned upside down. I could also lift the boat by grasping the extended handles on one of the cross pieces. The strength and rigidity the arches added to this boat led me to slightly arch the deck of the Z-PDR both bow to stern and gunwale to gunwale. Those arches helped solve one of the primary problems with the rectangular structures of the PDRacers—making the hull rigid.

 

Other features of Webfoot that found their way into the Z-PDR design were the low freeboard and extended bow concept. On Webfoot the bow transom is extended above the deck by about 5” and supported on either side by pieces that were left over from cutting the bow rocker from the 1” x 8” x 8’ cedar board that forms the bottom chine. On the Z-PDR, instead of being in line with the sides, these pieces were angled inward toward the bow, to both support the bow transom extension and to support the mast partner. (See the photos below.)

 

Diagram shows how the piece removed from the frame to form the bow rocker was reused to support the bow transom.

Angling these bow support pieces across the deck helps strengthen the boat’s structure.

 

One of the new features of the Z-PDR is a kick-up rudder that is both attractive and functional. The case and tiller are one piece and designed so that the outline continues the rocker, then curves back to form the tiller. A single bolt holds the rudder in place in the case, and a single length of shock cord holds the rudder in the down position or, when the rudder is lifted slightly, elevates the rudder high out of the water. Tightening the wing nut pinches the sides of the case together and holds the rudder firmly in place. This rudder case is a much more pleasing and functional design than I have seen on most small boats, and it particularly suits the low profile of the Z-PDR.

 

 

Rudder in the up position

Rudder in the down position

Case fitted to the stern transom

I designed Z to be a racing PDR, so the cockpit is bare bones and the ride will probably be wet. I coated the floor in the stern half with a sand finish paint for traction when moving from side deck to side deck. It is intended to be a “sit on” hull, not a “sit in” hull. A hiking plank across the decks is not out of the question.

 

To optimize her for racing, Z-PDR will have multiple sail, mast, and leeboard options. Currently, I have four sail options: A 58 sq. ft. battened sailboard-type sail, a 65 sq. ft. leg o’ mutton, an 85 sq. ft. leg o’ mutton, and a 100 sq. ft. high aspect balanced lug sail. Each sail has its own mast requirements, but by using a sectional mast, the mast length can be extended from 15’ to 18’ 6”. The basic 15’ mast has two 4’ aluminum sections and one 8’ bamboo section. This mast weighs in at just over 7 lb. and will float. This mast can be used for three of the four sails. If all goes as planned, only the 85 sq. ft. leg o’ mutton with its 17’ + luff will require the additional 4’ aluminum extension.

 

Four leeboards may also be available for the Z-PDR. One of the larger ones will have to be used on Wild Duck, but the others can be used at will. Three of the four boards are asymmetrical, while one is symmetrical and weighted. “Fat Bastard” is a short, nearly square board that will put over 440 sq. inches down in the water with a total length of only about three feet. On the other hand, the Big Aasymetrical Board is nearly as tall as I am, but with its hollow core is very lightweight. One thing that hasn’t changed much is my preference for a leeboard over a dagger board or center board. Once you build a trunk, it’s not easy to change boards except to make one longer or shorter.

 

Leeboard selection for the Z. “Fat Bastard” is the unpainted cedar board with the slot.

 

The Z-PDR awaits further testing at the Worlds in October. Skids and a seat might be in her future if she fails to perform as a racing PDR.

 

November 2009 Update

 

The 2009 World Championship race at Allatoona Lake, Georgia, was to be held on Saturday morning, October 16. I planned to arrive early on Thursday morning in order to do some final testing of both the Z-PDR and Wild Duck, the boat I planned to sail which hadn’t been in the water for over a year. The week leading up to the race, however, almost ruined those plans.

 

On Monday, October 5, my son and I trailered the Z-PDR out to Hutchison Island, not far from our home in Port St. Lucie, Florida, to try to get in a second test of the boat prior to the Worlds. Earlier, we had selected a spot for testing along the Intercoastal Waterway known as the Indian River Lagoon that was somewhat sheltered from the strong onshore Atlantic Ocean winds by the narrow barrier island. We hoped to try out a slightly larger 65 sq. ft. leg o’ mutton sail with the mast extension in place. As Ryan launched the Z, however, we observed storm clouds moving in from the southeast and the breeze beginning to kick up small waves. It quickly became clear that the sprit boom had been mounted too high on a loose snotter and was not doing its job of forcing out the clew. Instead, it began thrashing badly each time Ryan attempted to turn back toward shore. As the wind increased, the boom finally crashed against the mast and broke. Ryan quickly grabbed the pieces and tossed them into the boat, then managed to catch the clew and sail loose-footed in towards shore about a quarter-mile upwind of the launch point. Unfortunately, that area had a number of isolated rocks near the shoreline, and one of these holed the hull as he surfed to shore. Test two clearly showed the need for careful rigging and for strengthening the bottom, but the results were certainly not what we were hoping for. As luck would have it, that was the last time the Z-PDR was to touch the water until the World Championship races on Saturday.

 

Tuesday, Wednesday, and even part of Thursday morning were given over to repairs on both boats instead of beginning the loading process. I added two skids, repaired the hull, and epoxied the boom back together on the Z-PDR. Wild Duck got some repairs to her mast steps, gunwales, and stern, as well as some touch ups to the paint job. As a result, I arrived at the campground at Lake Allatoona at 2:30 a.m. on Friday morning. A detailed account of this preparation and the events surrounding the race itself are on my website at http://www.polysail.com/PDRWorlds.htm

 

Rigging Wild Duck. On  the left is John Wright’s lightweight PDR with the oval sail. The Z-PDR is in the middle. (Tim Cleary Photo)

Ryan launches for the start of race #1. The starting buoy and boat can be seen in the background. (This photo and all the following photos in this table courtesy of Ruth Leber)

Ryan leads a pack off the line in race #1. Notice the variety of sail types.

Wild Duck was performing well downwind, but I had already lost a half lap to the Z-PDR and the Bloody Splinter in the background

Ryan leads Australian legend and designer of the OZ PDRs Michael Storer on a run downwind. Eventual winner Shawn Payment is in the red boat in the background.

Ryan pulls the Z ashore after an exhausting day of three races.

Here’s a good look at the 58 sq. ft. sailboard-type sail with its sprit boom and small sprit spar. Ryan need to be forward a bit to balance the Z

 

 

In the end, the Z-PDR probably did about as well as could be expected with so little testing. Since we had only successfully tested one sail, we decided to use the small 58 sq. ft. sail for the races. A sail of this size was a decided handicap against many of the sails that approached 90 sq. ft., but the sail, design, and sailing skills of my son held up well against the competition, placing 4th against 13 other  boats. Ryan might have placed higher still, if I hadn’t asked him to help me out of a bad anchorage at the start of the third race. Even though he ran back to launch his boat, he was unable to get to the starting line in time for the horn. Consequently, the Z-PDR started race three at the back of the pack and never fully recovered since that race was only one lap. Wild Duck, on the other hand, was a disappointment, finishing 10th overall. As a result of a misplaced board, turns invariably ended with the boat in irons, and her 104 sq. ft. of sail area could not make up for that problem on fast downwind runs.

 

Further testing of the Z-PDR will come during the winter months here in South Florida. I will update this article after the next PDRacer event.

 

 

 

PolySail International

2291 SE Gaslight St., Port St. Lucie, FL 34952-7332

 Email polysail@polysail.com or call Dave Gray at 317 385-3444

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This page updated on 11/15/2009