What washers do within a bolt and nut joint.

Learn what is the fundamental purpose of what a washer does within a bolted joint. There are so many different sizes, colors, materials, and more, but they fundamentally perform just a couple main purposes of spreading out load and helping to secure the joint.

This is a basic tutorial of washer fundamentals for the average person, with an outstanding comments section, so be sure to read and expand your knowledge!

#mechanic #howto #learning

[crazyguy]

Back in tradeschool they also told us 2 other purposes behind flat washers, friction reduction and replacement. You have a rotating bolt head into a stationary surface, by having a plated piece between them you reduce the friction between the 2 and require less torque to achieve the same clamping force. On a similar note the rotating bolt head wants to chew into the surface under it, a flat washer is much easier to replace when it gets chewed than the entire workpiece.

[MaxTSanches]

Another function of washers is as a spacer. When bolting two plates together one, or more, washer(s) can be placed between the plates to get some separation.
At one of the factories I worked at we bought Washers for $10 per pound (about 10 cents each), and had apprentices file of any burrs and write a part number on them. They then became Spacers at $3 each.

[garyt]

The washers on the left are often referred to as (anti) Vibration washers. Washers are also to keep apart some materials for corrosion (electrostatic) and to prevent bolts "digging in" to softer materials. Good article, thanks

[markjohnson]

That's the kind of video I like. Covering something with a fair amount of detail, yet without a big time commitment. Keep doing that and I'll keep watching.

[mikelastname]

The first thing I did when I watched this was identify some washers in your small washer bin that were larger than those in you large bin - happily I kept watching and enjoyed the video. Looking forwards to seeing what's next.

[mikethespike]

I had a job for 2 years working as a washer designer. It's a real qualified engineering job.

[raylidell]

Thanks "Dad" for such an informative video. But of MOST value to me were the comments it generated from the viewers who weighed in with their experiences and insights on the other uses of washers and such. Its that input that made it of most value to me. Thanks

[anthonywalsh]

During my aviation apprenticeship we were taught a bolt has a plain shank, otherwise it is a machine screw. The bolt washer and nut assembled correctly would see the plain portion through hole and enough thread was when 1.5 threads were showing past the nut. Only fine thread bolts are used in aviation for better vibration resistance.

[ensen]

Good day.
You showed three types of lock-washers. I highly advise against using the first kind a.k.a. split washer / spring washer. Experiments have shown that those things are not just useless but they are worse than useless. Threaded connections with these lock-washer are more likely to loosen under vibration than connections without any lock washer at all. I have never seen the second type (might be a regional thing) but the third type works. The best ways to secure threads are with loctide or similar adhesive or those highly advanced lock washers like Nord-Lock or similar.
The more parts you stack over each other the more seams you have between the parts in a threaded connection. Over time the material in those seams ever so slightly yields away under the load and the nut / bolt connections becomes loose. Bolts and nuts with flange heads prevent that because you have less parts and with that less seams that will yield. If the connection is under vibration or thermal expension and contraction it is good idea to retorque after some time when everything has settled to compensate for the yield in the seams.

[hanzon]

Thanks for sharing this info. This plus comments from many learned viewers àre really instructive. Now i understand why and when all those different washers are used.

[commandersavage]

You forgot cross threading, nature's lock tight

[sailorsanjoy]

Great video . Very informative, thankyou

[Lee_In_AZ]

Washers also prevent the area under the bolt from being damaged during tightening, for example tightening on a painted surface.

[SEThatered]

One more function of a washer is separation of torque twisting between screw and the part.
For example on your bicycle the brake calipers are screwed through washers. And it is done to prevent the screw from rotating calipers out of alignment as you tighten them down to torque spec.

[kalijasin]

Really good information and explanation.

[nigelthompson]

In trade school I was informed “split” anti loosening washers strictly should only be used once. The “spring” effect not as important as the “bite “ of the spiked up edge at the cut of the split. Properly it should cut into the bolt head and the base metal to mechanically prevent backing out. Removing the bolt should damage the washer or base material. Consequently hardened high tensile bolt or base material will not get bitten into defeating the purpose.

[SFFXd]

Really helpful as this has been a burning question of mine for a few years. Now I know why. Thanks for sharing!

[gregfisher]

Great video again James, This is good basic information that should get most homeowners by. I know a lot of folks don't care what the function of a washer is. But us hardware nuts, so to speak, they are like the salt shaker on your kitchen table. Coming from an industrial background, we used hardened washer for certain applications, like when you have really need to tighten down on a bolt that in is place where there is a lot space around the bolt. A low grade washer will cave in under high torque were as a hardened washer will not !

[ChrisSchulte-yr]

We use those toothed washers for better electrical contact for grounding wire with a grounding screw. Those teeth ensure it cuts through paint/corrosion for better electrical continuity.

[wordreet]

I work in a precision engineering shop, and some who've been there years still add a washer under a nut that locks against a threaded hole in a vice side stop. And some never add a washer over a slotted fixing point in the vice side stop! Doesn't sound like much I know, but I just signed up on the Dull Men's Club, and it really matters to me.