From: "W. Ray Gibbons" <gibbons@northpole.med.uvm.edu>
He felt the locktab washers were
an outmoded technology, and no longer necessary if high quality bolts were
used and torqued properly. He pointed out that they are soft metal, and
deform under the bolt heads.
This is the real problem with these guys. Take at look sometime at a
used tab washer from a highly tightened fastener; you'll likely notice
that the metal is significantly squished where the fastener squeezed
it. The tab washer may well keep a loose bolt from falling out, but it
surely contributed to the bolt being loose in the first place.
IMHO the best thing to do is to use good quality hardened flat washers
(grade 8 SAE minimum, but mil-spec ones with precision-ground sides
are better) and get the bolts tightened right, at which point they
should stay put forever. If the situation is really critical, safety
wire the bolts - cheap peace of mind.
-john
John Wroclawski
jtw@lcs.mit.edu
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