MK III / MARK IV BROCHURE
MK III / MARK IV BROCHURE
The document introduces the Mark III and Mark IV Geartec propellers by Martec, highlighting their low drag and high performance for sailboats. The Mark III is noted for its simplicity and reliability, making it a popular choice for sailors over the past thirty-five years.
Specifications and Performance
The Mark III propeller is designed with a unique blade shape that offers reverse performance comparable to a fixed two-blade prop. It was initially developed for IOR racing boats to reduce drag and improve reverse thrust. The Mark III is efficient enough to stop a boat traveling at five knots in just one and a half boat lengths. It is suitable for a range of vessels from day-sailers to seventy-foot maxis.
Design and Innovation
Martec has continuously refined its folding propellers since 1964, creating a family of folding, feathering, and fixed blade props. The Mark IV Geartec is a rugged solution with larger gears and a compact hub and blade design for optimal drag reduction. It features large toothed gears for improved resistance to marine growth and fouling.
Saildrive Installation
Saildrives, which have replaced traditional engine configurations on some sailboats, require geared folding props. Martec's Geartec propellers are designed to meet these needs, allowing blades to fold at any point in their rotation.
General Features
The propellers are cast in high-strength marine bronze with Monel pivot pins and fasteners for improved anti-corrosion. They offer the lowest drag of any available folding propeller and provide sailing speed gains of 0.5 to 1.0 knots over fixed two-blade and three-blade props. The saildrive version includes a rubber cushioned hub bushing and comes with a five-year warranty.
Conclusion
Martec's folding props are recognized for their innovation and performance, significantly enhancing sailing speed and reliability. They are backed by thirty-five years of sales and service experience.
Catalog excerpts
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Open the catalog to page 1
"MARTEC FOLDING PROPS ADD SIGNIFICANT ! IN MODERATE WINDS, 0.5 KNOTS OVER 2-BLADE PRC ABOUT MARTEC ENGINEERING... Form follows function. Elegant. Sculpted.Powerful. Even more powerful performance. Our folding props deliver unparalleled performance, matching and bet- tering fixed two-blade props. Since 1964 we have continually refined and upgraded the Martec folding prop. We have redefined the concept of low-drag sailboat propellers, creat- ing a family of folding, feathering and fixed blade props. We've literally changed the expectations for sailboat auxil- iary power and sailing performance....
Open the catalog to page 2
JAILING SPEED OVER FIXED-BLADE PROPS. )PS AND 0.75-1.0 KNOTS OVER 3-BLADE PROPS." Gary Beck, Martec Engineering We call it the Mark IV Geartec. It's truly a rugged solution for a delicate problem. From the start we designed in bigger gears and a larger pivot pin for strength and reliability. Then we carefully integrated it with the most compact hub and blade design possible to achieve the best drag reduc- The large toothed gears (the largest of any geared folder) make the Mark IV virtually impervious teeth of some older teeth provide marine growth fourth generation blade figured for geared folders,...
Open the catalog to page 3
"THIS WILL DO MORE FOR A BOAT'S SAILING PERFORMANCE THAN ANYTHING I CAN DO TO A SUIT OF SAILS." GENERAL FEATURES • Refined blade design maximizes forward and reverse • Cast in high strength marine bronze • Monel pivot pins for improved anti-corrosion • Monel fasteners • Lowest drag of any available folding propeller Sailing speed gains of one-half to three-quarter knots over fixed two-blade & three-blade props Larger gear teeth for greater strength and reliability Saildrive version comes with rubber cushioned hub Five year warranty backed by thirtyfive years of sales 2257 W. Gaylord Street, Long...
Open the catalog to page 4