Washer stacking

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bagarre
Posts: 2615
Joined: Thu Sep 30, 2010 11:35 pm

Washer stacking

Post by bagarre »

Not to revive an old argument or beat a dead horse but,

I just had to share what I found on 95D's gear leg. I got a chuckle.
It wont be like this when it goes back together.
washers.jpg
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johneeb
Posts: 1520
Joined: Thu Jun 26, 2003 2:44 am

Re: Washer stacking

Post by johneeb »

All those washers and the near bolt does not have at least 1 1/2 threads showing! :)
John E. Barrett
aka. Johneb

Sent from my "Cray Super Computer"
bagarre
Posts: 2615
Joined: Thu Sep 30, 2010 11:35 pm

Re: Washer stacking

Post by bagarre »

johneeb wrote:All those washers and the near bolt does not have at least 1 1/2 threads showing! :)
LOL. I had already started to take that bolt off when I though to take a photo for posterity.
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c170b53
Posts: 2527
Joined: Mon Apr 22, 2002 8:01 pm

Re: Washer stacking

Post by c170b53 »

Oooh...backing plates..... :D
Jim McIntosh..
1953 C170B S/N 25656
02 K1200RS
bagarre
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Joined: Thu Sep 30, 2010 11:35 pm

Re: Washer stacking

Post by bagarre »

c170b53 wrote:Oooh...backing plates..... :D
To be accompanied by the polished wheel pants I have :)
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MoonlightVFR
Posts: 624
Joined: Sun Jan 02, 2005 5:55 pm

Re: Washer stacking

Post by MoonlightVFR »

Puzzling, why stack washers?

If the bolt was too long what bolt should be installed?


Was someone trying to adjust caster or camber?

Regards
gradyb, '54 B N2890C
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Bruce Fenstermacher
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Joined: Tue Apr 23, 2002 11:24 am

Re: Washer stacking

Post by Bruce Fenstermacher »

MoonlightVFR wrote:Puzzling, why stack washers?

If the bolt was too long what bolt should be installed?


Was someone trying to adjust caster or camber?

Regards
Answering the questions in reverse:

3. Yes, likely they were adjusting camber or caster or perhaps just replacing an axle.

2. Best practices specify a shorter bolt should have been installed.

1. Because bolt lengths are standard but those items dimensions the bolts are being used with rarely fit precisely within a standard grip length, washers are installed so nuts do not bottom out on the end of the thread before the bolt is properly tightened. Best practices, which mechanics are obliged to follow by the FARS unless other wise allowed, says that only so many washers should be stacked and only so much thread should protrude through the nut yet there is also a minumum threads showing through the nut standard.

As manufacturers do not have to follow best practices, over the years, specially in older aircraft, you can find situations where one can not acquire a bolt whose grip length is such that one can meet all the best practices of stacked washers and threads showing. Back then, they used common sense, when stacking washers and how many threads protruded through the nut, something not found in abundance today where everything has to be spelled out in a book or manual with no room for common sense.

David's examples show someone who did not follow best practice nor did they get as close as they could have.
CAUTION - My forum posts may be worth what you paid for them!

Bruce Fenstermacher, Past President, TIC170A
Email: brucefenster at gmail.com
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