Using washers under nuts

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Dark Knight
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Using washers under nuts

Post by Dark Knight »

I must be a bit of a geek as I found this quite interesting.
When I was an apprentice I was told to always use washers under nuts.
Maybe this is because I was was working on Avionics which probably used lower torque fixings.
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Dark Knight
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Re: Using washers under nuts

Post by Dark Knight »

This guy does not state what level of torque and size of bolt that he is talking about.
I usually use mild steel washers and have never seen any apparent distortion over tens of years..
On the bigger bikes the highest torqued bolt, would the rear wheel spindle at 80 ftlbs (old guy, using old tools made to last).
I suppose the washer under the retaining nut could be high tensile steel.
I think this guy is talking about bolts and fixings used in building bridges or similar.
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Asgard
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Re: Using washers under nuts

Post by Asgard »

Not just the heavy stuff, there is a fair bit discussion on this subject amongst some aero engine techs, most old flat 4 and 6 cylinder engine use through bolts that hold the 2 opposing steel cylinder/head assemblies and both crankcase halves together and its quite a problem getting the correct preload stretch on these long through bolts....Washer material has come up in the discussions relating to the different torque recommendations that exist for the same engine as well as lubing or not the thread and indeed throwing away the torque wrench altogether and buying huge calipers to actualy measure the the bolt stretch!!
Its a trick............get an Axe
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Asgard
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Re: Using washers under nuts

Post by Asgard »

P.S. Nord-lock X series washers seem like a promising method for preserving bolt preload, Ive got a few ready for a flywheel replacement I need to do in the future
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Re: Using washers under nuts

Post by Dark Knight »

I always use grease on the bolt threads to stop them rusting up, some people never follow the rules!
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Re: Using washers under nuts

Post by garyboy »

i have been wondering about this for a while now.
i was always led to believe that washers were always a good thing ..anywhere and everywhere.
but that badly fitting washers can mess things up a bit.
I always felt that the use of washers lessened the torque strength of a bold/screw, but never thought of the rough -surface/ friction, effect, which would dissipate the original torque at every surface.
I notice that these days bikes don't seem to have a large washer under the big nut at the rear axle.

I have noticed that there is a big difference if, eg, you tighten up the nut, as opposed to the bold head... especially at the rear axle and at the rear chain cog nuts.

I had my chain tightened at my local mechanic, as a favour while changing a tyre. I noticed that the assistant tightened from the bold head side .... when i got home i tightened up the axle from the nut side ... loads of movement .. by hand with a small leverage hand spanner, 27mm. ... doh..
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Re: Using washers under nuts

Post by garyboy »

Dark Knight wrote: Mon Feb 01, 2021 6:26 pm I always use grease on the bolt threads to stop them rusting up, some people never follow the rules!
copper slip sems to be the boyo .. but i ant got nun aas it is a bit deer .. lol
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bowber
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Re: Using washers under nuts

Post by bowber »

Asgard wrote: Mon Feb 01, 2021 3:11 pm and indeed throwing away the torque wrench altogether and buying huge calipers to actualy measure the the bolt stretch!!
The manual for our old Leyland buses gives a measurement for bolt stretch instead of a torque or angle (big end cap bolts)

I much prefer the flanged bolts and nuts, they dont make a mess of aluminium (or other soft surfaces) like a washer does.

Steve
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Re: Using washers under nuts

Post by garyboy »

bowber wrote: Mon Feb 01, 2021 6:59 pm
Asgard wrote: Mon Feb 01, 2021 3:11 pm and indeed throwing away the torque wrench altogether and buying huge calipers to actualy measure the the bolt stretch!!
The manual for our old Leyland buses gives a measurement for bolt stretch instead of a torque or angle (big end cap bolts)

I much prefer the flanged bolts and nuts, they dont make a mess of aluminium (or other soft surfaces) like a washer does.

Steve


i dont get that???
doesnt the washer help the bolt slip until almost fully tight .. so saving the ali??
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Re: Using washers under nuts

Post by bowber »

You'd think so wouldn't you but the flanged nut spreads the load much better and doesn't distort like a washer does, the proof is in the pudding and I see far less damage from a flanged nut than a washer on regularly removed nuts. A classic is the rear wheel nut on an Aluminium swinging arm, I bought a new oem flanged nut for my KTM, my mate fitted a nut and washer, it wasn't long before his swinging arm looked a mess with the edges of the slot starting to burr over etc, an extreme example as if he'd used a new washer each time there wouldn't have been as much damage but my swinging arm still looked fresh and flat with no marks.

Steve
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