Ronstan Series 75 Core Single Halyard Block
- Class leading performance and sleek, contemporary styling
- Excellent dynamic and high static load performance
- Less than half the friction of the nearest competitor
- Durable aluminium alloy cheek plates
- Central hub hole can be used as a becket take-off or tie-up point
- Suits direct attachment to mainsail headboard for 2:1 halyard
- Removable 8mm (5/16”) threaded pin at head
- Acetal roller on head pin to suit spliced line attachment
- Alloy Rope/Wire sheave version also available
- Sheave Ø 75 mm
- Max. Rope Ø 14 mm
- Max. Cable Ø - mm
- Pin Ø 8 mm
- M.W.L. 1500 kg
- B. L. 3000 kg
- Weight 234 g
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.
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.
- 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.
- Sheave: U.V. stabilised acetal or anodised aluminium (AW models).
- Cheek plates: Aluminium alloy
- Ball Bearings: High compression strength carbon black acetal.
- Pin: 2205 stainless steel
All orders are shipped from our Brookvale, Sydney order fulfilment centre. Orders are normally shipped within 5 business days - most quicker!
Shipping day estimates after your order leaves our fulfilment centre in Sydney are based on Australia Post domestic delivery times:
|ACT||2 - 4 business days||1 - 2 business days|
|NSW||2 - 4 business days||1 - 2 business days|
|NT||7 - 10 business days||3 - 4 business days|
|QLD||3 - 5 business days||2 - 3 business days|
|SA||4 - 6 business days||2 - 3 business days|
|TAS||5 - 6 business days||2 - 3 business days|
|VIC||3 - 5 business days||2 - 3 business days|
|WA||6 - 9 business days||3 - 5 business days|
Last updated 11/08/2022
* These delivery times are an estimate and actual delivery times may vary based on peak periods and other external factors. Bulky orders may take longer.
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Get a shipping rate estimate by adding items to your online cart. Go to the cart by clicking on the shopping cart icon located at the top right of the page. Then enter your shipping destination information into the "Estimate Shipping and Tax" section of the shopping cart summary.
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