SD2

Radio Control Boat Modeler, Dec 2001 by Dunlap, Jerry

BOAT REPORT

Record-setting .20 deep-vee

SEADUCER BOATS

In addition to the array of tunnel boats I stuff into the back of my pickup for model events, I often include a .20 vee-hull. A fine running .20 vee definitely grabs my attention, and while attending the 2001 International Model Power Boating Association (IMPBA) Internationals in Milan, IL, I saw Jerry Crowther capture three of the four U.S. I awards in the monoplane class with his Seaducer vee-hulls. At that event, the performances of all the Seaducer hulls were impressive; Jerry was enthusiastic and very willing to share his extensive knowledge.

THE HULL

The Seaducer SD2 design features a 20-degree vee, low-- profile sides and a deck that channels the airflow over its length. This deck design is common to all the Seaducer deep-vees, and it gives them a distinct appearance. The bottom of the SD2 incorporates two ride strakes on each side along with a 3/16-inch flat surface that runs the length of the bottom chine. A slight "hook" (concavity) built into the bottom allows the boat to handle the water well without trim tabs-- rather uncommon for a vee-hull. The SD2 is a very rigid model boat; all Seaducer hulls are made with Kevlar glass cloth and are hand-laid up during the molding process. Motor-mount rails are glassed into the hull to accept a mount developed especially for this boat.

Seaducer hulls are available in various stages of completion; choices range from basic hulls to ready-to-run boats. If requested, Seaducer Boats custom-paints boats for its customers; the drip (or splatter) paint scheme is popular. To save myself time and effort, I ordered my hull with the hardware and fuel tank already installed. However, the installation of the hardware in the SD2 is typical of any model-deep-vee. A photo-illustrated instruction booklet is provided to help you install the running hardware, the radio box and the motor. I strongly recommend that you follow the directions and install the recommended hardware.

I accepted an offer from Rick Alexander, New Lenox, IL, to paint the boat. Rick applied a striking three-tone "tear" paint scheme incorporating dark metallic blue, light blue and white. Sponsor/product decals completed the hull finish.

RADIO INSTALLATION

The Seaducer SD2's radio box is not the typical, rectangular shape. It is tapered; the front section is lower than the rear, and that yields a low profile inside the hull. To ensure the proper alignment of the servo output arms and the rudder and throttle pushrods, the servos should be installed slightly canted in the radio box. After you've installed the rudder and motor, mark the locations for the output rod holes and seals in the radio box. Drill the holes where the rudder and throttle linkages touch the box. I used G&M Models radio-box seals and control rods to connect the linkages to the servos. A high-performance Futaba S9301 servo handles rudder control, and I installed two Futaba S3101 mini servos for throttle and third-channel mixture control.

My only problem when I installed the radio system was that I cracked the clear Plexiglas radio-box lid. I used a drill bit that was too big when I drilled the hole for the on/off switch. Rather than purchase another piece of Plexiglas, I made a radio-box lid from 1/16-inch plywood. It worked, but a clear lid is a good idea, as it allows you to visually check for water in the radio box.

When the boat is stopped on the water, the rudder-linkage exit hole in the transom lets water into the hull. To correct that problem, I created thin rubber gaskets and secured them to the front and back of the rudder-- linkage hole.

POWER UNIT

The power for my Seaducer SD2 is a CMB 21 LS Greenhead. "LS" stands for long stroke, and, as its name implies, the cylinder head has been anodized green. I first saw one of these engines at the 2000 IMPBA Internats. Bobby Himel, the model marine expert at Tidewater Engineering, ran one in his 20 hydroplane.

Along with importing CMB model marine motors, Tidewater Engineering also provides boats and model boat accessories. Racing his Jaguar 20 outrigger, Bobby won the 20 Hydroplane heat racing event. After seeing that performance, I decided that I wanted a CMB 21 LS Greenhead for my Seaducer; Tidewater supplied me with a 21 LS and CMB 21 Quiet Pipe for this project.

The 21 LS has proven itself to be a powerful easy-to-start engine. The carburetor is easy to adjust, and it provides an excellent idle. Once broken in, the engine transition from idle to full throttle is smooth and linear. The sound-damping capability of the CMB 21 Quiet Pipe is excellent; it's nice to be able to go fast and not make excessive exhaust noise.

CLOSING COMMENTS

There's an old NASCAR expression, "What wins on Sunday, sells on Monday." Without question, the winning record of the Seaducer SD2 greatly influenced my decision to acquire the boat. In recent years, Seaducer boats have won national championships and have established records in straightaway speed and oval competitions. A Seaducer 60/80 belonging to Jerry Crowther and powered by a CMB 67 just took the ultimate monohull straightaway record at a little over 78mph. Top speed is great, but we also race around comers; national championships and two-- lap oval records document the cornering capabilities of the Seaducer hull.