Ronstan Series 55 Orbit Ratchet Block with Becket
- Brand:
- Ronstan
- Part no:
- RF56110
Image: velasailingsupply.com
Where to buy
Specifications
- Bearing
- Ball
- Becket
- Yes
The Ronstan Series 55 Orbit ratchet block has a becket and a ratchet that works in automatic or manual mode. Its sheave is anodised aluminium running on ball bearings, inside a frame of glass fibre reinforced nylon. The maker quotes holding power of up to 20:1, from a sheave with 12 gripping faces that resist loaded line movement. The sheave diameter is 2 5/32 in.
Our take
Up to 20:1 holding power is the maker's figure for the sheave's gripping faces, so the block does the holding work itself. In auto mode the ratchet engages under load and switches off when load is released, so the sheet eases out freely.
From our buying guide
Ball-bearing blocks give the lowest friction on lines running under moderate loads. Plain bearings have more friction, but handle very high and static loads.
Check before you buy:
- A ratchet block is rated for the full sheet load.
- Any becket's load limit suits the job, since a becket can be rated below the block itself.
- A soft-attach block will be looked after, since Harken warns soft attachments are prone to wear and recommends them only for regularly maintained race boats.