Ronstan Series 75 Core Block, Single RF74100
$153.85
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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 the resilience 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.
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.
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.
Universal head
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.
Features:
Applications:
Materials:
Specifications:
Sheave Ø: 75mm(3")
Max. Rope Ø: 14mm(9/16")
Pin Ø: 8mm(5/16")
M.W.L.: 1,500kg(3,300lbs)
B. L.: 3,000kg(6,600lbs)
Weight: 354g(12.5oz)
Ronstan Series 75 Core Block, Single RF74100
$153.85
Usually ships in 1 to 3 business days.
Delivery is usually 2 to 5 business days after it ships.
Delivery is usually 2 to 5 business days after it ships.
- Free shipping to the lower 48
- 30-day returns on unused parts
- New Ronstan part in the original packaging
Not sure it is right for your boat? Email hello@apertureauto.com with the boat make, model, year and engine. We will check before it ships.
Questions? Email hello@apertureauto.com. We reply within one business day.
Overview
Ronstan Series 75 Core Block, Single, manufacturer part number RF74100.
Series 75 Core Block - SingleCore 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 the resilience 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.
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.
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.
Universal head
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.
Features:
- Class leading performance and sleek, contemporary styling
- Excellent dynamic and high static load performance
- Less than half the friction of the nearest competitor
- Universal head with full 3-axis articulation
- Head posts can be locked at 0 or 90 degrees, by using a 2.5mm Hex/Allen Key
- Central hub hole can be used as a becket take-off or tie-up point
Applications:
- Ideal for mainsheet, halyard and spinnaker sheet applications on boats to 14M (46')
- Various control line applications on larger yachts
Materials:
- Sheave: U.V. stabilized Acetal
- Cheek body: Aluminium Alloy
- Ball Bearings: High compression strength carbon black Acetal
- Shackle, head post & hub: Grade 316 stainless steel
Specifications:
Sheave Ø: 75mm(3")
Max. Rope Ø: 14mm(9/16")
Pin Ø: 8mm(5/16")
M.W.L.: 1,500kg(3,300lbs)
B. L.: 3,000kg(6,600lbs)
Weight: 354g(12.5oz)
Specifications
| Manufacturer part number | RF74100 |
|---|---|
| UPC | 9316800413225 |
| Type | Sailing Hardware |
| Country of origin | Australia |
| Shipping weight | 0.95 lb |
Compatibility
Check the specifications above against your boat or vehicle. Not sure? Email hello@apertureauto.com with the make, model, year and engine, and we will confirm before the order ships.
Questions and answers
Is this part new?
Yes. It is a new Ronstan product. Manufacturer part number RF74100, UPC 9316800413225.
What does shipping cost?
Shipping is free to the contiguous United States. It ships from an East Coast warehouse and tracking is emailed as soon as it ships.
Can I return it?
Yes. Unused, uninstalled items in the original packaging can be returned within 30 days of delivery. See the refund policy for details.