Ronstan 75mm Cheek Block - RF74151
Ronstan RF74151 S75 Core Block, Ideal for use on mainsheet, spinnaker sheet, vang, halyard and backstay applications on boats up to 14m (46ft).
General applications on larger yachts.
Class leading performance and sleek, contemporary styling
Excellent dynamic and high static load performance
Less than half the friction of the nearest competitor
Only two fastener holes - minimises deck sealing considerations
Scalloped cheeks - allows for variations in line lead
Mount with 2 x 10mm (3/8") fasteners (not supplied)
Sheave Ø 75 mm
Max. Rope Ø 14 mm
M.W.L. 1500 kg
B. L. 3000 kg
Weight 259 g
Universal Bearing - Dynamic and high static load performance
The Ronstan Universal Bearing incorporates our proven 2-stage bearing system
Stage 1 - Under moderate loads, Acetal ball bearings ensure minimum friction.
Stage 2 - Under heavy loads, where deformation of ball bearings alone would result in increased friction, a sliding Acetal bearing on a polished stainless steel race takes over, maintaining low friction performance.
Additionally the ball bearings are configured to act as a thrust bearing between the sheave and cheeks, preventing the sheave from rubbing on the cheeks and causing friction when the line lead in and out of the block isn’t perfect. Particularly important for cheek blocks.