Mercury Racing has launched a new 300hp Five-Blade CNC Cleaver propeller designed to maximize outboard performance. The propeller features a new surface-piercing proprietary blade, that delivers stronger acceleration and top-end speed, than the Mercury Racing 400hp CNC Cleaver prop.
While mainly aimed at twin‑outboard catamaran applications, this new propeller design will also take single‑engine, padded‑vee‑bottom and tunnel boats to a new level of performance.Steve Miller, Mercury Racing, Director of Marketing, Sales and Service
This new propeller — produced with CNC machining — has unique benefits that overshadow standard cast propellers, according to Mercury Racing. To ensure lift, handling and speed characteristics are consistent on every Mercury Racing CNC propeller, special attention and rigorous tests are conducted on their pitch, diameter and rake.
The 300hp Five‑Blade Cleaver prop is designed and manufactured to reduce slip percentages in outboard Sport Master applications — averaging 4.5 percent at wide‑open throttle (WOT).
“Slip” is an often misunderstood propeller term that directly relates to boat thrust. That’s why Mercury Racing includes an explanation of slip percentages on their website and a Prop Slip Calculator.
Slip is not a measure of propeller efficiency. Rather, slip is the difference between actual and theoretical travel resulting from a necessary propeller blade angle of attack. If the blade had no angle of attack, there would be no slip; but, of course, there would be no positive and negative pressure created on the blades and, therefore, there would be no thrust.
Want a behind-the-scenes look at how propellers are manufactured? PowerBoat Television recently produced a video tour of the Mercury Marine factory in Fond du Lac, Wisconson. It’s one of the most popular videos on PowerBoat TV’s YouTube channel.