2022 Ronstan Marine Catalogue - Flipbook - Page 70
FEATURES & INFORMATION
Soft Attachment Blocks
SA block sheave
Cheek plates twist to open block
Soft shackle & titanium dog bone
SOFT ATTACHMENT BLOCKS
Designed from the outset to deliver outstanding performance, these blocks
achieve the highest ratings for dynamic load vs sheave diameter in our
keelboat block range. They are built to perform and built to last. Every SA
Block features fully machined, anodised aluminium cheek plates. Sheaves run
on duplex stainless steel hubs and incorporate precision composite journal
bearings and thrust washers. The soft attachment is a purpose designed
Dyneema® SK99 cord shackle with titanium dog bone.
Ultimate dynamic and static load performance
SA Blocks incorporate a full contact, self-lubricating composite journal bearing running on
a polished duplex stainless steel hub, to maintain low friction performance under heavy
dynamic and static loads.
Thrust washers in the same composite material are positioned between the sheave and the
cheek plates to handle the high side loads that can be generated when line entry and exit
alignment is not ideal. Testing has shown reduced friction and greater durability than ball
bearings in this application.
Attach, detach and open
The soft shackle provides a simple means of attachment, secured with the titanium dog
bone but easily opened when necessary to detach the block.
With the shackle open a gentle rotation of the cheek plates opens the head of the block so
it can be fitted to a standing line. To close the block, rotate the cheeks back to the closed
position until the spring loaded ball lock secures them in place. No additional external straps
or bands required.
Soft shackle with titanium dog bone
Drawing on the expertise of Nodus Factory, many design iterations were tested before
finalising specifications of the Dyneema® SK99 cord shackle and titanium dog bone.
Proprietary Nodus Factory splicing techniques and fibre surface coating ensure secure load
transfer from the block and maximum durability.
Aluminium alloy cheek plates & sheaves
Block cheeks and sheaves are precision machined from high strength aluminium alloy,
anodised for durability and corrosion resistance. The soft attachment through the hub
provides a protective buffer between the block and boat surfaces. Retaining guides in soft
elastomer ensure that the block remains aligned within the soft shackle.
A multitude of applications
Suited to temporary or permanent line deflection, load carrying and snatch block applications
including: 2:1 Main halyards, headsail and spinnaker sheets, mast base halyard deflection,
and running backstays.