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Ronstan 75 mm Series 75 Core Mast Base Block

  • Single Mast Base Block with Clevis Pin Head
  • Maximum Line Size: 9/16"
  • Maximum Working Load: 3300 lbs
  • Item #: 
    603526
    Brand: 
    Ronstan
    Model #: 
    RF74108A
    Shipping Weight: 
    0.60 Lbs.
    List Price: 
    $90.53
     :
    $76.95
    76.95
    Status:      In Stock

    Quantity:  
     
     

    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.

    Features:

    • Class leading performance and sleek, contemporary styling
    • Excellent dynamic and high static load performance
    • Less than half the friction of the nearest competitor
    • Durable aluminum alloy cheek plates
    • Central hub hole can be used as a becket take-of or tie-up point
    • Suits direct attachment to 14 mm (9/16") wide mast collar post
    • Removable 8 mm (5/16") clevis pin at head

    Specifications:

    • Safe working load: 3300 lb (1500 kg)
    • Breaking load: 6600 lb (3000 kg)
    • Weight: 8.1oz (230g)
    • Sheave diameter: 3" (75 mm)
    • Maximum line size: 9/16" (14 mm)

    Applications:

    • Ideal for use on mainsheet, spinnaker sheet, vang, halyard and backstay applications on boats up to 14m (46ft)
    • General applications on larger yachts
    • Alloy sheave models are available for use with wire

    Materials:

    • UV stabilized acetal or anodized aluminum sheave (AW models)
    • aluminum alloy cheek plates
    • High compression strength carbon black acetal ball bearings
    • 2205 stainless steel pin

    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 optimization and the cut-away design minimizes 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, minimizing rope wear.

     

     
    WARNING: This product MAY expose you to chemicals, which are known to the State of California to cause cancer, birth defects and/or other reproductive harm. For more information go to www.p65warnings.ca.gov



     


    Ronstan 75 mm Series 75 Core Block
    Item #: 603522
  • Single Block with Swivel
  • Maximum Line Size: 9/16"
  • Maximum Working Load: 3300 lbs
  •  Include


    $107.95
    Model #:
    RF74100
    Ronstan 75 mm Series 75 Core Block
    Item #: 603523
  • Single Block with Aluminum Wire Sheave with Clevis Pin Head
  • Maximum Line Size: 9/16"
  • Maximum Working Load: 3300 lbs
  •  Include


    $165.95
    Model #:
    RF74100AW
    Ronstan 75 mm Series 75 Core Block
    Item #: 603524
  • Single Block with Becket with Clevis Pin Head
  • Maximum Line Size: 9/16"
  • Maximum Working Load: 3300 lbs
  •  Include


    $127.95
    Model #:
    RF74110
    Ronstan 75 mm Series 75 Core Halyard Block
    Item #: 603525
  • Single Halyard Block with Clevis Pin Head
  • Maximum Line Size: 9/16"
  • Maximum Working Load: 3300 lbs
  •  Include


    $101.95
    Model #:
    RF74108
    Ronstan 75 mm Series 75 Core Foot Block
    Item #: 603527
  • Single Foot Block
  • Maximum Line Size: 9/16"
  • Maximum Working Load: 3300 lbs
  •  Include


    $119.95
    Model #:
    RF74151
    Ronstan 75 mm Series 75 Core Double Block
    Item #: 603528
  • Double Block with Fixed Head
  • Maximum Line Size: 9/16"
  • Maximum Working Load: 3300 lbs
  •  Include


    $209.95
    Model #:
    RF74202
    Ronstan 75 mm Series 75 Core Stand-Up Block
    Item #: 603529
  • Single Stand-Up Block with Swivel Head
  • Maximum Line Size: 9/16"
  • Maximum Working Load: 3300 lbs
  •  Include


    $199.95
    Model #:
    RF74140
     
     
     

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