Introduction to the class rules
Keeping Bottom 10" Of All Hulls Alike
The class rules are aimed at keeping the bottom 10" shape of all the boats the same, but the foils and sails are up to the ducker. The hulls are the most complicated and time consuming part to build, so it is very important to keep them all alike. If the hull shape was allowed to vary (whether it actually improves performance or not), then older shaped hulls would be viewed as obsolete, causing people to feel like they had to build a new hull to stay competitive, which destroys the entire concept of this racer. Once a person builds their hull, they freely alter all of the other variables with the boat such as the sails, foils, rigging etc. Those are the parts that are easy and quick to alter - that is why we focus on changing them instead of the hull.
Additional Goals of The Rules
Also a goal that an average person can build a complete boat from scratch, for a reasonable cheap price, compete in the annual world championship race and have a reasonable chance at winning with that boat. Boats built from common plywood CAN be made lighter, cheaper and just as smooth compared to fiberglass or carbon fiber. The tolerances that describe the hull shape are set loose enough that a person new to building boats can make reasonable mistakes during the building process, and still end up with a boat which conforms enough to be considered "class legal". NOTE: The tolerance range is meant to save sloppy building, and NOT to be intentionally used during construction.
PDRacer Class Rules
Defined Hull Shape:
This is our defined hull section, this is the perfect shape of a finished boat, however most of us use this as the cut plan of our side panels. The tolerances are setup so that you can use this as your cut plan.
The hull panel is 8' long.
The hull panel is 18" high (however a 16" hull seem to be preferred by most).
minimum required is 10" high.
The station marks are 12" apart, from left to right (stern to bow) they are:
6", 2-5/8", 5/8", 0", 0", 1", 2-3/8", 4-3/8", the last point is 6" from the end, it is 6" up from the base line.
For a metric conversion of the Defined Hull Shape [click here]
NOTE: The length of the hull depends on the height of the sides. For more info, see How to cut the bow angle
1 - The hull must match the lower 10" of the defined hull shape
A - The "end points" are the corners where the bottom meets the bow and stern transoms.
B - The distance between the end points may be as long as 91" or as short as 89-7/8"
C - The proper way to measure the rocker shape is from a straight line between the "end points" on a finished boat.
D - The station marks are measured from the stern end point, which is offset horizontally toward the middle by the formula (length - 90" / 2)
E - The rocker shape of the finished hull must fit within the defined tolerance range below.
F - The rocker shape is to be in the form of a curve
G - The boat must be sailed so the bow angle is normally facing forward.
H - Having a hull number does not guarantee the hull is class legal
2 - The hull must have flat parallel sides, flat bow and stern transoms, and a flat bottom
A - The chines and hull edges may be rounded, maximum of 1" fillet as per this drawing
B - The stern transom may be partially or fully open, however the sides must still be the full height.
C - Slots for foils are OK.
D - The sides and transoms must continue to be flat and parallel, even above the 10" line, except for a gunnel or hiking wings (or other similar shaped extension) with the following restrictions:
must be above the 10" line
must be perpendicular to the side of the hull
must not extend more than 6" beyond the hull
must not be thicker than 1.5"
3 - The hull must be 48" wide
A - The beam has a 1" tolerance (makes for minimum 47", max 49").
4 - The hull must have enough emergency flotation to be self rescued
For more info about flotation, see: Emergency Flotation
5 - No external flotation chambers (such as pontoons, cut waters, amas etc.)
A - Mast head floats are exempted from this rule, and are OK to use.
6 - No lifting foils (hydro foils)
A - All foils must be vertical
B - Maximum of 1.5" wide fins (centerboards, keels, rudders etc)
C - Foils may extend forward or aft of the hull, and may extend vertically above the gunnel.
D - Foils may be attached to the sides of the hull.
7 - Don't screw with the hull shape
A - Anyone with a registered puddle duck who is participating in a "puddle duck" event, has the right to request the measurement of any puddle duck hull which is also participating.
B - Nobody shall impede, prohibit, or otherwise try to restrict (or make un-cool) this right of any puddle ducker.
C - If a measurement is requested, that request and the measurement must take place before the race, or before that hull's first participation in a series of races.
D - If a registered hull is found out of tolerance, that hull can still participate, the maximum penalty a ducker can request is that the results of the hull are not counted, and that hull will delay it's start untill all the class legal hulls have crossed the start line.
| Station | 1 | 2 | 3 | 4 | 5 | 6 | 7 | over to bow |
| Above | 2,7 | 0,7 | 0,2 | 0,2 | 1,2 | 2,5 | 4,5 | 2,2 |
| Ideal | 2,5 | 0,5 | 0,0 | 0,0 | 1,0 | 2,3 | 4,3 | 2,0 |
| Below | 2,3 | 0,3 | -0,2 | -0,2 | 0,6 | 2,1 | 4,1 | 1,6 |
Official Rule Interpretations
David "Shorty" Routh is the founder of Puddle Duck Racer sailboat class, sole administrator of the class & rules, and sole owner of the Puddle Duck Racer trademarks. I have made my best effort to keep the rules as simple and easy to read as possible in laymen terms. If you have a question about the meaning of the class rules, try looking through the following pages:How to cut the bow angle
Rule Explanations Page
How to Measure A Hull
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