SeaStar Solutions Catalog

3 ® STEERING - Overview Mechanical cable steering is durable and reliable and comes in two main forms, each of which has advantages in specific applications. They are: • Rotary (cable wraps around a gear). • Rack & Pinion (cable attached to rack gear moved by a pinion). All mechanical steering systems except Big-T are for single station use only. Hydraulic steering is the perferred system for dual station boats. ROTARY STEERING (2 TYPES): Various Rotary helms are available, each resulting in a different number of lock-to-lock steering wheel turns. All SeaStar Solutions helms feature a unique mounting plate that allows installation at several angles to accommodate the many space constraints which occur behind all dashboards. Most versions are available with No FeedBack (NFB) technology. NFB is recommended for all outboards and stern drives without power-assisted steering. HPS and Safe-T QC are offered for most boats with power- assisted steering. Big-T is a good choice for small inboards, especially those with twin stations. There are two main rotary helm designs: Reduction Gear Type: (one or more gears mesh externallywith the drumtomove the helical core of the steering cable). This is the best rotary design in terms of strength and efficiency as there are usually only two gears. The one drawback is that the helm shaft must be placed outside the cable drum, resulting in a fairly large round helm behind the dash. These helms often cannot be used in small dashboards. The original, time-proven SeaStar Solutions helms such as Big-T ® and Safe-T ® were designed with reduction gears, resulting in simple, efficient gearboxes. With smaller, more crowded dashboards came the need for a more compact helm, thus one with planetary gears to save space. Planetary Gear Type: (three or more gears mesh internally with the cable drum to move the helical core of the steering cable). This is an alternative rotary design whose purpose is to take up the least possible space behind the dash, useful in boats with small dashboards and/or instruments clustered right around the wheel. RACK AND PINION (1 TYPE): There is only one kind of Rack and Pinion. A pinion gear hobbed directly into the helm shaft engages a rack gear in a tubular housing. Rack and pinion steering is the most efficient mechanical approach to moving the cable. The drawback is that it requires a long tubular rack housing and cannot fit behind many dashboards. SeaStar Solutions rack mounting allows installation of the rack tube at several different angles, but because it is very long, there is not as much mounting flexibility as with rotary helms. The Rack (without the NFB feature) is offered for most boats with power-assisted steering. DUAL (TWIN) CABLE SYSTEMS: All mechanical steering systems rely on a push- pull cable to do the work of moving the engine or rudder. The efficiency of the system depends on the efficiency of the cable. By virtue of their design, all cables have some backlash or lost motion. While this is acceptable for most boats, some high performance boat/engine combinations develop instability at high speed. Instability becomes more prevalent in boats faster than 50 MPH. Dual cable (or SeaStar PRO) steering is recommended by SeaStar Solutions and engine makers for these boats. Dual cable steering allows adjustment at the engine of one steering cable versus the other to remove most of the backlash (free play) inherent in even the best mechanical systems. This reduction of backlash helps minimize engine flutter and the resulting handling instability. Mechanical and Hydraulic Steering Overview Generally, it is a good practice to replace a steering system with one of the same type: rotary with rotary (i.e. Safe-T ® ), rack with rack (i.e. The Rack™), hydraulic with hydraulic (i.e. SeaStar ® ), etc. Use a steering system with the same number of steering wheel turns lock-to-lock as the original system. This insures the boat continues to perform in maneuvers as designed and makes installation of the replacement system as simple as possible. Changing the type of steering on a boat requires some careful consideration. Your steering system was selected by the boat builder based on the following criteria: • Fit: steering components accommodate dash design and splashwell dimensions. • Performance: meets manufacturer’s performance specifications. • Value: quality products supplied by a reliable, experienced company that stands behind them. Any change from the original steering system may affect the handling and feel of the boat. In addition, installation may be further complicated by modifications needed to accommodate components for which the boat was not originally designed. About Our Mechanical Steering Designs