Core Blocks™ are a true all round solution. A tuned 2-stage bearing system provides excellent performance across the full working load range with an integrated thrust bearing feature and there silience to handle high dynamic or static loads.
Acetal sheave, alloy cheeks and stainless fixings complete the durable package. For reliability and a long service life, these blocks are the right choice for sheets, halyards and control line applications for cruising and racing.
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.
Alloy cheek plates
Block cheeks are manufactured from the highest quality alloy for maximum strength. Material optimisation and the cut-away design minimises weight and allows easy fresh water rinsing of salt and debris from the bearings.
Cheek design has been further styled with flaring at the block throat and reduced gap between the cheek and sheave, minimising rope wear.
The head assembly incorporates a brass bearing washer to provide smooth 360° rotation of the post and shackle.
A set screw arrangement allows the head to be locked at 0° or 90°.
Shackles are high quality forged grade 316 stainless steel.
Suits pre-spliced lines
Removable becket pins allow fitting of pre-spliced lines. The flush fit becket pin head is kind on deck surfaces and won’t snag lines.
Fully articulated stand-up
Stand-up models have a low profile linkage that provides full rotation and articulation. A high strength precision cast padeye minimises the footprint and a dedicated rubber boot ensures the block is held upright when not loaded.
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