Technical Lock washers, yes or no

I have never had a lock washer break and fall out. I have pulled some things apart and found the lock washer broken. I us them a lot as well as lock-ite and start washers depending on where the bolt or nut or both is and what was used originally if I can find out.

while I am a little remis in some applications I have discovered that proper torque is the best tool in your box.

 

Larry, when I do use a lock washers I generally use stainless steel, I also have several boxes of stainless steel star washers, but they will damage a painted surface. HRP

 

not a favorite mag here but, in Feb 2020 Hot Rod there is part 2 of Nuts About Bolts that provides a lot of info that explains differences with nuts, bolts, washers, etc - worth a look

 

Last time I was finishing school I had to take a structural class. We were not allowed to draw a single bolted joint without a proper flat washer and lock washer. The type of washer was or is determined on the type of load, the size of the bolt and the given torque spec.

Here is a funny side note. I was working on a highway design project before I finally decided to officially retire. I was working primarily on walls, sound barriers and retaining walls and got loaned out to bridge design for a couple of weeks. The lead engineer on the project dropped a design small design project on my desk. (note I am not a PE) and reminded me that there needed to be a torque spec for every bolt. I asked him why if every bolt was torqued that there needed to also be a lock washer (split washers is what spec required) and he said, "because iron workers don't use torque wrenches." and laughed.

 

As you and JVO mentioned, aircraft (mil-spec) 'Hi=Lok' nuts and swedged lock nuts are the best. I worked in the aircraft industry in my younger years, was absolutely sold on them and still use them today in critical (suspension) areas on vehicles. Hi-Loks are typically mated with titanium fasteners in aircraft and critical race car components. The hex breaks free once proper torque is established, leaving a threaded collar in place that isn't coming off (unless you cut it off). It's essentially a threaded, bucket rivet.

Star and Nord Lock washers; Stars are generally not reuseable, while Nord Locks can be reused if you confirm the grooves are not overly worn.

Nyloc's; Most people don't realize nyloc nuts are usually only grade 3, so keep that in mind when you're wrenching them down on your expensive grade 5 & 8 suspension component bolts! Also, be mindful of repeat use, as they will eventually lose their torque value. High grades are usually the ugly gold zinc finish but high strength can be found all the way up to mil-spec from sources such as McMaster-Carr;
https://www.mcmaster.com/nylock-nuts

 

Purely engineering wise, split lock washers are almost useless (you can look it up to verify). One little single point of locking feature. Not used in the Aerospace Industry..!
Inner or outer star washers are a much better design. They have a great many points of locking feature.
BUT, like much of the offshore stuff we have, even the offshore versions, those are crap. American made star washers are a much better, safer buy than split washers.

All metal locking nuts are the best metallic locking device, with Nyloc's being second best. The main reason that the Nyloc's are second best, is that they need replacing more often than a full steel nut.
Also, not a good idea to spin either of these nuts quickly. Friction causes heat, excessive heat is bad for both of these nuts, moreso the Nyloc's.
Again...buyer beware of offshore locking nuts..!

Then there are the locking compounds. Just don't use the red Loctite on anything under about 5/16" dia., you'll never get it out.

Mike

 

I use all lock washers (star washers internal or external and countersunk, spring lock, ones with tabs). Nylocks look bad and are a single use only (I know this is a great debate and my cars never stay put together, I always take stuff apart). On a fan you could use an external star washer. I, like most people are not pulling out a torque wrench for a fender or fan bolt......maybe a lug nut.

They came on the cars from the factory and last time I checked my cars aren't going to fly or take a trip to the space station.

 

The fault in that experiment was the use of thread lubricant on all the bolts. Use of a lubricant changes the torque requirements and that can screw up the clamping force of the fastener, either not enough clamping force, or too much (and a stretched bolt/stud that will fail under load). It's important for any fastener used in a critical application to use or not use a lubricant as prescribed by the OEM engineers.

 

So the results in the Nord-Lock video contradicts all of you, the split washer performed far better than no washer or flat washer.

 

I’ve never had a lock washer break and fall out. I’ve taken old stuff apart and had broken washers but they hadn’t backed off and let the washer fall out.
My single seater project I’m doing I have a 1950 cutoff so no parts other than a duel master cylinder are being used so no nylocks being used here. I’ll stick with lock washers.

 

I've had this book for many years so not sure if it is still in print but a very valuable resource if you can find it.

 

Those are good under ground bolts.

 

Another good locker is using nordlocks. it's a technology used on all sorts of rotating equipment. Materials range from carbon steels , stainless and inconel. They can be purchased from a variety of hardware ( Fastenal and others). I have them on my traditional looking 29 Dodge and Willy's. I also have used them on gas turbines. Look them up online.

 

You are thinking of Stover nuts.

Jet nuts are nuts with a built in washer flange that is full diameter but uses a smaller wrench than normal. IE: on a 1/2” stud a jet nut uses a 9/16” wrench instead of a 3/4” wrench.

SPark

 

I thought he was looking for washers to use with bolts. I agree with the comments about using good quality lock nuts when possible.What I have done is make some nut and bolt bins and then buy stock off of Ebay to fill them up. I save all the hardware I remove from any vehicle if its decent. I find that for building cars and trucks I need a lot of shorter bolts. While I visit Tractor Supply and buy bags of quality bolts for projects, I also like to stock up on "washer head" bolts that have serrations on the bottom of the head. They spread the grip out over a larger area and the serrations bite well enough to prevent loosening You can't hardly find them locally and if you do, they are expensive. I looked on Ebay and you can get 50 5/16-24 (fine thd) for about $20 and free shipping. These happen to be Grade 5. I buy lots of these bolts and keep the bins full. Really handy and I like them on my projects. Some of these should hold a fan in place just fine.
Something else HAMBers might find useful is a "Concrete Bolt" supposedly for securing things during Hurricanes. It has a large head compared to the thread size and can work well for areas where someone might like a little extra support behind a panel or something.





Here are some shorter ones with coarse threads to show what you can get.
https://www.ebay.com/itm/200-Serrat...991574?hash=item41ffd48356:g:oLcAAOSwh8dcxFnf
Serrated Nuts
https://www.ebay.com/itm/600-1-4-20...lVQSFg:sc:USPSPriorityFlatRateBox!40109!US!-1

Some Grade 8
https://www.ebay.com/itm/200-Grade-...hash=item2ec33f88ad:m:m8u8rAPLmzDquuINRCs0MXQ

Not that any of you HAMBers would ever need them, but its a good place to stock up on Metric nuts and bolts too.

 

So, being the rebel that I am I installed my fan with my newly machined spacer (1” cut down to 3/4” because a 3/4” fan spacer is something you can’t buy) with new grade 8 bolts and flat washers, no lock washers like I’ve done on countless cars over my life.

Just tightened them properly.

 

GMC pickup yes, Chebbie pickup no

 

I have over 1000 pages of study data.

You have one video.

 

There is one style locknut (non nylon insert) to be cautious of, I can't remember the name but years ago the assembly department at work had done a "clean out", and I grabbed a box of them that had been thrown in the dumpster, I was told not to use them because they pull the bolt threads when removed.
These had multiple slits on one end and were necked down similar to other versions currently available, luckily I tested a few on some bolts and sure enough, EVERY ONE pulled the threads so be careful.

 

Interesting Lock Washer Test:

 

I could believe you or my lying eyes......

 

Blues -

Don't care about what they (Nord-lock) say.
And the next time you fly somewhere..thank the Aerospace folks that THEY do NOT...use split lock washers..! They don't want an engine or a wing falling off !

PLUS...the absolute BEST form of locking a nut to a fastener (that I don't see mentioned)...castellated nut with a hole in the fastener for a cotter pin. Used a fair amount in the Aerospace Industry, along with friction steel locking nuts.

Mike

 

It's kinda funny, but on another thread there is a discussion about the demise of many of the automotive magazines relevant to the world of hot rodding. Many say they quit reading them many years ago because they became too general rather than hot rod specific. Personally I enjoyed reading them and gleaning info from them and always felt I got my money's worth. The surviving(so far) magazine is "Hot Rod" . What's funny is that they have a great 8 page article with really good info and pictures on " nuts and bolts". I mean "really really good", especially for someone without a lot of experience.......but even the knowledgeable wrenchers can learn a thing or two. Those of you who still have a subscription should look at their Feb 2020 edition and enjoy the article. Those of you who let their subscriptions lapse will just have to wonder what they missed. And I'm telling ya........it's really really good!

 

Well, I suppose we have to consider the application and how aerospace best practices apply to hot rods. Caterpillar believes there is value in split lock washer technology, think they know a thing or two about the issue? What is closer to 50 year old hot rod technology, Caterpillar off road heavy equipment, or aerospace applications?

BTW, it's not what Nord-Lock says, it's the results of the Junker test. Do you doubt that split lock washers prevent unintentional loosening of fasteners better than no washer or not flat washer? Look at the results of the test. Are they the absolute best technology for preventing unintended loosening? No I wouldn't say that, but they are obviously better than nothing at all.

 

All of the GM and NASA data says that you are wrong.

I am not going to argue this issue with you, or anyone else. My work is trusted to keep millions of people safe. No company I work for, or consult with, will allow a split-lock washer, on any application, ever.

There is a reason for that.

Facts can save your life. Faith can get you killed.

 

If I ever decide to try and fly my car rather than drive it,I’ll look for alternatives,but the good old split lock washer used for countless years will do me and my family fine.
Obviously there is better out there but in my application they’re not required.
IMHO

 

Have never used/seen a lock washer on a connecting rod bolt. You'd think those would be subject to some vibration...

 

There may be other considerations: I've noticed that spilt washers when removed show that the washer dug into soft metals pretty good but hard steel, not so much. A Nord-lock stretches the bolt when removed. Does that warrant caution when reusing a previously stretched bolt? On several occasions I over torqued a split washer and had it spread out under the bolt head. I like star washers on electrical stuff because they dig in through paint and other coatings for good electrical contact.

 

Some engines require them as there is a recess made for the lock washer. Didn't Model A use a castle nut and cotter pin? I think some Cadillac connecting rods used lock washers.

 

There always are. For aerospace you can be sure they have taken into account how heavy the fasteners are. Special nuts where the six sided part is broken off after correct torquing makes perfect sense, it removes dead weight that does nothing useful between installation and removal, it ensures the nut is correctly torqued, and it makes sure the fastener is never reused.

You know the Helicoil style thread inserts that people use to repair stripped threads? Supposedly they come from aerospace, as a weight saving idea. A small bolt was strong enough for the job, but the thread in the alloy the bolt went into had to be larger to be strong enough. Instead of using the larger, heavier bolts they added the thread insert, making a small bolt fit a larger threaded hole.