Plain bearing, ball bearing and roller blocks; how should I choose a type of block?

28 | 04 | 2020

On a sailing yacht, the choice of a block is important to facilitate manoeuvring, improve performance and preserve the equipment. At Wichard, we offer several ranges of blocks depending on their applications.

First, we should remember that rigging on a sailing yacht can be divided into 3 categories:

  • Dynamic operations and low load: it involves large movements under moderate load, such as for spinnaker sheets and poles.
  • Dynamic operation and heavy load such as backstay or mainsail sheets
  • Static operation and heavy load: this involves little rope movement, such as mast foot blocks.

For blocks, we need to differentiate between:

  • Plain bearing blocks
  • Ball bearing blocks
  • Roller blocks
  • Sheave-less blocks, such as friction rings

Plain bearing blocks have a sheave rotating on a stainless-steel pin. They are intended for static operation and heavy loads such as mast foot and mast head blocks and also reefing points, cunninghams, downhauls, backstay adjusters and boom vangs.

Wichard ball bearing blocks are fitted with two rows of Delrin balls. They are ideal for dynamic operations and low load such as spinnaker poles and sheets, spinnaker tacks, mainsheets and mast tracks.

Wichard roller blocks: By replacing the balls with rollers these blocks can also withstand heavy loads in dynamic operations: main halyards , mast tracks, spinnaker tacks and backstay adjusters.

Finally, sheave-free blocks such as FRX friction rings, MXLEVO soft blocks and MXEVO blocks have in common the absence of sheaves. They are therefore used mainly in standing rigging with high loads: backstay adjusters, mast-foot blocks, mainsail feet, barber-haulers, etc.