Wing Strut Bolts - Washers?

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LSHAvenger18
Posts: 21
Joined: Thu Apr 26, 2018 8:58 am

Wing Strut Bolts - Washers?

Post by LSHAvenger18 » Tue Mar 05, 2019 4:46 pm

We are just about to fit new wing strut bolts to an Auster J1N.

The book (not updated since 50s/60s) clearly shows no washers under the bolt heads.
The aircraft arrived with washers under the bolt heads!

Does anyone have a best practice please?

Thanks,

Simon
Simon Heighway
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coxargus
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Re: Wing Strut Bolts - Washers?

Post by coxargus » Tue Mar 05, 2019 5:04 pm

I have found the same anomaly during my Argus rebuild - are the bolts the correct length? - I found some that were one size too long.
Frank Cox
Frank Cox
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Bill McCarthy
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Re: Wing Strut Bolts - Washers?

Post by Bill McCarthy » Tue Mar 05, 2019 6:44 pm

I would put the washers under the bolt heads in order to spread the load in the area, act as a bearing surface- if the hex heads “dig in” without them, they can tear the undersurface.
032125

LSHAvenger18
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Joined: Thu Apr 26, 2018 8:58 am

Re: Wing Strut Bolts - Washers?

Post by LSHAvenger18 » Tue Mar 05, 2019 9:39 pm

Thank-you Bill, those were my thoughts too.

Yes thanks Frank, they look correct length.

Simon
Simon Heighway
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austerity
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Re: Wing Strut Bolts - Washers?

Post by austerity » Wed Mar 06, 2019 7:47 pm

The strut tangs are a loose lateral fit in the fuselage fitting so the bolt should only be nipped up otherwise the fitting will be distorted. I think washer as necessary to achieve this with the plain shank taking all the load.
Neil Geddes
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LSHAvenger18
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Re: Wing Strut Bolts - Washers?

Post by LSHAvenger18 » Wed Mar 06, 2019 7:59 pm

Thank-you Neil,

good info,

Simon
Simon Heighway
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