StarCruzer
More details on the remarkable 23-foot trailersailer by Pat Bretthauer
The StarCruzer is a 23-foot trailersailer. She weighs 1800 pounds empty and can carry 1200 pounds of water ballast. The weight of the boat with the trailer is about 2800 pounds. It draws 48" with the boards down and 12" boards up. It is self-righting to a 135-degree heel angle, and the total sail area is 269 ft^2, with a max cabin height of 65”. The primary mission is 2-3 day trips on the Chesapeake Bay.
The StarCruzer took five years to build and was launched in April 2021. It was designed and built by me with help from my friend and boat designer Geoff Bland.
The project began with the following requirements:
The weight of the boat and trailer needed to be less than 3500 lbs so it could easily be towed by a class II vehicle. I use a RAV4 Adventure.
It had to be self-righting to 120 degrees of heeling angle.
My wife, Joy, needed a 64" cabin height to stand up in it.
It was mandatory to have an enclosed head.
It needed space for four people to overnight.
It needed to serve as an RV for road trips and overnights.
It needed a six-hp outboard motor.
It had to be as large as possible while keeping the above requirements.
I analyzed twenty-four vessels to gain experience creating a boat of this size. Geoff and I considered many ideas before we came to the final configuration. Then a 3d CAD model was made with Rhino3d software. It would have dual bilge boards to keep the middle of the cabin free of obstacles. Because it has a wide beam, it needed dual rudders to ensure reasonable control at high heel angles. It would have room below the cockpit for a sleeping berth. Righting stability would come from water ballast.
Next, I built a 10% scale radio-controlled model for testing. This model helped evaluate the sailing performance and bilge board location. The model was water ballasted to test its righting ability. The model was also helpful in ensuring that the CAD-created parts would fit together accurately. I also tried several different sail designs on the RC model. In addition, I made a full-scale cardboard head to ensure it had enough space.
I decided to use water ballast instead of lead ballast. The ability to drain the ballast before towing allows the boat to be much bigger and still make the 3500-pound towing limit. Forward and aft ballast tanks are below the cabin's floor, with a central filling station. The tanks fill up when launched, and a bilge pump empties them before leaving the water. I coated the ballast tank interior with seven layers of epoxy and West Systems 422 barrier additive.
The hull is 9 mm Okoume plywood covered with fiberglass and epoxy. The rudders and bilge boards are ¾" pine reinforced with carbon strips and covered with fiberglass. They are spring-loaded down, so if the boat runs aground, they will automatically retract.
For the hull, three sheets of plywood were scarfed together to make one large, 24 ft long sheet of plywood. An HP DesignJet 24" plotter was used to make the 24' full-size hull plank and bulkhead drawings. The drawings were then adhered to the plywood with 3M Super 77. I used a jigsaw to rough cut out the parts and a belt sander to bring the plywood accurately to the lines. The boat was dry assembled right side up. I drilled holes and used zip ties to hold the parts together. Once everything was in the right place, I glued it together with thickened epoxy. The joints were filleted and reinforced with fiberglass strips. I used Sapele wood to make the rub rails and keel strip. The hull was fiberglassed, and I applied three layers of epoxy. After much sanding, it was primed and painted with topside paint.
A finite element program was used to calculate the load on the mast and stays. I analyzed 9 different loading conditions for 13 different mast configurations. Finally, I chose a mast with a single spreader, 3 upper stays, and 2 lower stays. I purchased a mast from Dwyer Mast Company. The stays are 3/16" stainless cables connected with Nico press-style fittings and turnbuckles.
I designed the sails using Sailcut CAD software. The main sail is 160 ft^2, and the jib is 109 ft^2, for 269 ft^2. The main sail has a single reef point, and the jib uses roller furling. The HP plotter printed the full-size patterns; the panels were cut out and sewed together using a Singer Heavy Duty sewing machine. The fabric comes from Sail Rite and is 5.4 oz. Dacron.
The StarCruzer launched in April of 2021. It has accumulated about 120 hours of sailing time. It is still "experimental," and more testing is needed. It has been out in as much as 20 knots of wind. The max speed so far is 8.0 knots, but it is more comfortable cruising at 4-6 knots. Above 13 knots, I reef the main sail and roll up the jib as needed. From arriving at the ramp to sailing takes about 1.5 hours. I have yet to sail other boats of this size to know how it compares.
I want to thank my wife, Joy, for her encouragement on this 5-year project. So far, we have enjoyed many sailing trips, including the Chesapeake Bay, Lake Winnipesauke, and Lake Chaplain. I am looking forward to many more seasons of sailing. •SCA•
This is a Wonderful Project. Kudos aplenty. It does remind me of the Swallow Bay Cruiser 23. Dimensions are very much a mirror. Just have to ship it from England to the U.S.
I salute Your build and Your completion of the project !!!!!!!