Malcom wrote:
[snip]
WARNING!!! Don't use that block for loads even approaching 2000
lbs.
There is no way you can buy any ball bearing block with a SWL
rating of
2000 lbs for $12.00--stainless strapped or otherwise. If you
paid
$12.00--and it is a BB block--the SWL is probably 200-300 lbs,
possibly
500 or so lbs, and certainly no more than 900 lbs.
Ball bearing blocks have substantially lower load ratings than
plain
bearing blocks and cost dearly when you reach the 2000 SWL level.
The
cheapest 2000 lb SWL BB block that I could find in a marine
discount
catalog was over $80.00.
Block SWL ratings are typically 1/4 of the absolute maximum
ratings
(read point it breaks) although it can vary by manufacturer.
E-mail me any names, numbers, and/lettering on the block and I
can
probably find the true SWL spec for you.
If there are no markings send me a full description including
measurements and materials and I will probably be able to give
you a
ball park estimate. Again, there are no $12.00 2000 lb SWL
blocks--including plain bearing. $120.00 2000 lb SWL BB
blocks--yes.
73
Malcolm KR4HP
***************************************************************
I absolutely agree with Malcom. My posting on the Harken "pulley"
was intended only to advise persons looking for weather-proof
pulleys for holding up loops and dipoles. Do not waste your time
trying to find $12 blocks that can handle 1000 pounds.
Tod, K0TO
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