[TR] difference between these two washers

[Don Hiscock]

Carroll Smith, perhaps?  :)

(He did indeed work with Caroll Shelby, though.)

On Fri, Feb 3, 2023 at 3:04 PM Dave MacKay <dave at mdmackay.ca> wrote:

> >Date: Fri, 3 Feb 2023 09:31:17 -0800
>
> >From: Sujit Roy <triumphstag at gmail.com>
>
> >To: Triumphs <triumphs at autox.team.net>
>
> >Subject: [TR] difference between these two washers
>
> >
>
> >Besides, looks, what are the differences between these washers? Why use
> one compared to the other? I typically see the left one used for lighter
> loads, but never under a load which needs torquing up.
>
> >Sujit
>
> >
>
> >Sujit Roy
>
> >Cupertino, California
>
> >URL: <
> http://autox.team.net/pipermail/triumphs/attachments/20230203/1f2337ba/attachment-0001.jpg
> >
>
>
>
> On pp 116-117 of Carroll Shelby’s *Nuts, Bolts, Fasteners and Plumbing
> Handbook*, Shelby discusses the lock washers including star washers (like
> the one on the left of the image) and spring lock washers (like the one on
> the right of the image).
>
>
>
> “Lock washers
>
>
>
> There are a great many locking devices on the market today. The most
> popular is also the least effective --- the lock washer. There are three
> basic types of lock washers: the spring washer, the wave washer and the
> serrated, or star, washer.
>
>
>
> Nether the spring washer nor the wave washer do anything worth talking
> about --- other than to provide the user with a false sense of security.
> Think about it for a moment. From experience, you know that it takes very
> little load to compress a spring washer. For example, the spring washer
> will be completely closed long before we reach recommended torque when
> tightening a bolt. Once compressed, the spring washer is nothing but a flat
> washer. If, for whatever reason, a bolt should loosen to the point where
> the spring washer opens enough to become a spring, there was too little
> residual stress in the assembled bolt for any sort of safety. In other
> words, the thing wasn’t tightened sufficiently. Exactly the same is true of
> the wave washer which is, for some reason or other, popular in Germany. If
> you decide to use a spring lock washer, a flat washer should be placed
> between the lock washer and the work surface to prevent damage to the
> surface. This in not necessary with the wave washer.
>
>
>
> I am willing to admit that there are installations where the serrated or
> star washer can be effective . These installations are limited to the
> smaller sizes and almost always have to do with machine screws bearing on a
> rather soft surface --- aluminum or plastic, for example. The teeth of the
> washer can and do bite into the surfaces of soft materials and offer
> reasonably positive protection against rotation. They are available with
> either internal or external teeth, and also as coned washers for
> countersunk bolts.
>
>
>
> I try not to use lock washers. I use prevailing torque-type self-locking
> nuts on all through holes and check or jam nuts to lock rod end bearings
> and threaded adjusters. With blind holes, if I do not trust the thread
> portion of a properly tightened bolt, I use the appropriate grade of
> Loctite and/or safety wire. I do, however, carry a selection of aircraft
> spec (AN-935) spring lock washers [similar to the one on the right of the
> image] around with me --- just in case. I will not use industrial [rather
> than aircraft-grade] spring lock washers because they are liable to be too
> brittle for my taste.”
>
>
>
> Dave MacKay
>
> 1960 TR3A (s/n 68639L)
>
> Near Toronto, Canada
>
>
> ** triumphs at autox.team.net **
>
> Donate: http://www.team.net/donate.html
> Archive: http://www.team.net/pipermail/triumphs
> http://www.team.net/archive
>
> Unsubscribe/Manage:
> http://autox.team.net/mailman/options/triumphs/don.hiscock@gmail.com
>
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://autox.team.net/pipermail/triumphs/attachments/20230203/ea7b645d/attachment.htm>