Click to enlargeRonstan Series 55 Ratchet Mount Orbit Block - Fiddle Becket Swivel
Manufacturer: RonstanPart #: RF56510SKU: 70708
- Nylon
Item #: 70708
Category: Blocks
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Description
Series 55 Ratchet Mount Orbit Block - Fiddle Becket Swivel Features: Up to 20:1 holding power Smooth easing of sheets High performance cleating Automatic ratchet block Now you can enjoy the flexibility of setting up your ratchet blocks to suit yourself. Ronstan is the only company that offers a ratchet block with both auto and manual engagement modes*.
In the auto mode of the ratchet mechanism engages when load is applied, but switches off when it's released. This lets the sheet run out smoothly and freely-great for rapid easing of the sheet and for gybing asymmetric spinnakers.
In manual mode, the ratchet mechanism can be switched on or off as required. This is the preferred mainsheet set-up for may top sailors.
Try the block in both modes and see which you prefer - you really can't go wrong. * Selected Series 55 models.
Awesome ratchet block holding power Quite simply, Ronstan Ratchet Orbit Blocks™ have the highest holding power available. The sophisticated NC-machined sheave features Generation 2 of our patented sheave cross-hole geometry.
Its holding power is up to 21:1, almost double that of our nearest competitor. The unique sheave design has 12 gripping faces which directly resist loaded line movement.
Traditional designs have only 8 faces with an angled resistance to line movement. Our Generation 2 design has straight resistance faces which both distribute the load and minimize rope wear.
These faces are offset from the radial line, to draw the rope down into the gripping area when under load Materials: Sheave: Anodized Aluminium Ball Bearings: High compression strength carbon black Acetal Frame/Cheeks: Toughened, glass fiber reinforced Nylon Rope Link: UV stabilized, multi-strand impregnated SK75 Dyneema®
Specifications
| Brand | Ronstan |
|---|---|
| Part Number | RF56510 |
| EverTide SKU | 70708 |
| UPC | 9316800480241 |
| Material | Nylon |
Specifications are provided by the manufacturer. Confirm fitment for your application before ordering, or contact us and we'll help.
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Returns & warranty
Returns are accepted within 30 dayson items that are unused and in their original packaging. Some items may be subject to a manufacturer restocking fee. Special-order items may not be eligible — if you're unsure, ask us before ordering.
Ronstan productscarry the manufacturer's standard warranty. For a warranty claim or a return authorization, see our full returns policy or contact us.
Sailing — frequently asked
- How do I size a block for my sailboat?
- Match the block to the line diameter it will carry and to the working and breaking loads of the system (sheet, halyard, control line). Makers publish load ratings and line-size ranges — choose a block whose working load comfortably exceeds the real-world load, without going so large it adds needless weight.
- What is running rigging?
- Running rigging is the moving lines that control the sails — sheets, halyards, and control lines — as opposed to standing rigging (the fixed wire that holds up the mast). Running rigging should be matched to the boat’s blocks, clutches, and winches for smooth, reliable sail handling.
- How do I maintain sailboat winches and hardware?
- Rinse with fresh water after sailing, keep sheaves and bearings clean, and periodically service winches (disassemble, clean, and re-grease per the maker’s instructions). Marine-grade stainless and good maintenance keep hardware working smoothly when loads are high and timing matters.
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