Blocks
Ball
Bearing vs. Non-Ball Bearing Blocks
Blocks are used in purchase systems on sailboats so sailors can better
control the high amounts of load created by wind and sails. The way
to make this difficult task simpler is by designing blocks that run
freely and reduce the friction caused by sheets and lines in purchase
systems. So what is the difference between ball bearing blocks and non-ball
bearing blocks?
Ball
Bearing Block
Ball bearing blocks are best for any system on your boat that does not
see "static loads," or low-movement applications. Examples of a few
recommended ball bearing block applications are main, jib, and spinnaker
sheeting systems, traveler cars, and controls, and running rigging backstay
runner blocks. Compared to non-ball bearing blocks, ball bearing blocks
run freely allowing for increased safety and ease of use. Whether cruising
or racing-the sailor can only exert a limited amount of power, so ease
of operation and ability to release a line and let it run free is very
important and is optimized with ball bearing blocks.
Non-Ball
Bearing Blocks
Non-ball bearing blocks are best fit for applications that hold high
static loads and/or only change line direction, such as turning blocks,
masts base blocks, deck organizers, halyard blocks, boom vangs, and
reefing blocks. In these instances, a simpler, less expensive, non-ball
bearing block makes the most sense.
Safe
Working Load vs. Breaking Strength: What is the Difference?
Safe working load is the maximum load that a block can handle while
still working properly. Breaking strength is the load at which a block
will begin to yield and start to deform. When loaded to its breaking
strength, the block can be damaged to the point beyond normal use and
repair. As a rough rule of thumb, a block's safe working load can be
determined by dividing its breaking strength in half.
It is important to know the amount of load your blocks will see in their
specific application in order to choose the right block for the application.
If you're unsure, consult a marine professional, such as your sailboat
manufacturer, sailmaker, or sailboat hardware manufacturer.
Block Care and Maintenance
Ball bearing blocks are designed to reduce friction. When saltwater
residue and dirt are introduced to the races of ball bearing blocks,
friction increases, and ball bearings can wear. The largest enemy of
any plastic ball bearing block is dirt and debris.
Knowing this, caring for your blocks is simple. Be sure to thoroughly
wash and rinse your blocks with soap and freshwater as often as possible.
If you sail in saltwater, it is best to flush out your blocks after
every sail.
For increased performance, try spraying your blocks with a dry lubricant
like Team McLube SailKote in the ball bearing races of your blocks.
Dry lubricants like this repel water and contaminants that can harm
ball bearing systems. In almost all cases, one application will last
an entire season.
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