Out Rigger Hull Setup (Hydro Plane)
Out Rigger Hydro style Radio Controlled boats are a pure all out speed racing machine. They are very different from the average hull style. These high performing Rigger hulls are extremely fun, however it takes some degree of work to tune them to run to their full potential. They have been derrived from the typical Hydro Plane hull. With no extra body material, large cowlings or wings, it’s design encourages reduced drag.
Out Rigger style Racing Hulls are designed in such a way that they perform their best only at Wide Open Throttle. Slightly off throttle and they will not perform as well. This style hull is capable of cornering at a typical Oval Race Course turn radius at full throttle. The attached turn fin described later is the main source for this amazing characteristic. At slow speeds the Out Rigger Hull will not be able to turn well. It must be fully on plane. From a dead stop, and the pure nature of an Out Rigger style hull having very little volume to float well, the hull rests quite deep in the water. At initial throttle the booms connecting the tub to the outer sponsons will plow through the water and in many cases are nearly fully submerged. In some situations, the hull it self sits so low that if it catches the slightest wake, it could possibly dive in to the water.
Hull Designs are usually pushed to every limit. This is standard practice in the nature of any type of racing. However sport boaters can set this hull up for a more conservative type of setup.
> When purchasing the strut for ang Out Rigger Hull, it is important to keep in mind the depth the strut must reach. Commonly with a strut for an Out Rigger Hull, the section that holds the prop shaft tends to sit further ahead of the mounting surface. This is different from a strut that would be used with a Mono Hull.
When mounting the strut on an OutRigger hull it is important to determine the final position the strut will be setup in, for the first initial run. This is due to adjustments that can be performed to the strut for fine tuning. The reference position for the strut and this will also be the first run position, is where the center prop line of the strut is even with the furthest bottom surface or edge of the sponsons. This only holds true in a OutRigger style hull that has rear sponsons or an equivalent. If not the strut centre line should be placed aboout 3/8 of an inch below the bottom surface for a 33 inch hull. For a hull around 26 inches in length the strut should be around 1/4 inches in depth. If your hull is different in length, the position should be proportional to the ones provided. This will be the reference position and first initial run position. When mounting the strut is is important to allow adjustment room for raising or possibly lowering the unit. Allow 60% of total adjustment for raising the strut. Keep in mind when raising the strut the screws will reach the bottom of the adjusting slot as the screw remains stationary and the slot slides up. Allow the remaining 40% of the total adjustment for lowering the strut. For example if the strut allowed exactly 1” of height adjustment, 0.6” would be for raising the strut and 0.4” would be for lowering the strut. Prop shaft angle should be set to 0 degrees or neutral for the first initial run. Refer to the drawing below for a better visual of the OutRigger Hull Setup.
The turn fin on an Out Rigger style hull is mounted on the right sponson. An Out Rigger turn fin is shaped with a curve at near the bottom. This is to allow the hull to hold the corners very well.
It may be mounted at the very rear of the sponson as in the photo, or it may be mounted up to a few inches further behind the right side sponson on the Out Rigger Hull by using a boom.
Rudder with Water Pickup
A rudder is essential for steering any RC OutRigger Hull boat. Select one that is best suited for your hull length. Around 15% of the hull length is a good approximation or starting point. It is recommended but not required to select or choose a rudder with a water pickup. If there is no water pickup in the rudder it is recommended to use an external pickup.
Center of Gravity
Center of Gravity on an Out Rigger Hull is typically where the turn fin is Mouted. This may be at the rear of the main sponsons or just a few inches behind.
Refer to the Drawing. THe drawing references the above material.