Don't use lock washers and other stuff you didn't know

[crakarjax]

I was looking into thread locking compounds and ran across an engineering firm that studies bolt loosening and failures. The takeaway is that lock washers actually decrease the preload curve of fasteners! It's mentioned on the site also that regular washers also have a detrimental effect, which is disappointing because I use them to avoid scratching up paint when fastening. I'm not sure if the use of thread locking compound would make up for using flat washers in that case.

http://www.boltscience.com/pages/hel...ingwashers.htm

http://www.boltscience.com/pages/vibloose.htm

[jjzepplin]

Ahh nuts!

[ERASER5]

Originally Posted by jjzepplin

Ahh nuts!

What you did there. I see it.

My brother sells fasteners and anything else a maintenance crib needs. According to him, split ring lock washers are a tool of the devil. And has the data to prove it. Take close look at grade 8 bolts. On the bottom of the bolt head, there is a raised portion. Using no washers, the hex never touches the part. Only the smooth ring, like a built in washer. A lock washer completely negates that as well as cuts into both surfaces. That's just one example. And his hacksaw blades? He can tie them into a knot, then untie them no worse for wear.

[Willie Makeit]

anything you'd ever want to know about fasteners. lots of math.

https://standards.nasa.gov/file/515/...token=cXwrFsu2

[crakarjax]

Originally Posted by Willie Makeit

anything you'd ever want to know about fasteners. lots of math.

https://standards.nasa.gov/file/515/...token=cXwrFsu2

Did you read that and if so could you summarize the findings? At a glance it looks way too dry to keep me awake

[special-K]

I have real world experience to prove those work from the top down types wrong. I don't need to say they are wrong, maybe they are right. But, all I know is in my years I have never had these washers cause any detrimental effect. So, even if they are right by their data, it's a moot point. Fact is, it really doesn't matter. Weren't engineers involved in the design of these washers and all the products they've been used on since before corn flakes were invented?

[crakarjax]

I'm leaning toward this stuff on all my nuts; I would like to try the gel compound but it doesn't call out oil resistance and I think that's a big bonus in my application.
https://www.amazon.com/gp/product/B0...d4b1c6519c0709

This is the gel stuff, and it seems like a better deal per ounce really.
https://www.amazon.com/gp/product/B0...1e43ce26309a7f

Originally Posted by special-K

Weren't engineers involved in the design of these washers and all the products they've been used on since before corn flakes were invented?

Engineering has evolved quite a bit since the late 1800s, and they certainly didn't have the capability of testing the efficacy of these things back then.

https://www.google.com/patents/US514...D2AYkQ6AEIPzAF

How do you know these had no detrimental effect? Did you have side by side nuts and compare the rate at which their tension decreased over time? I'll take empirical evidence over anecdotal every time.

[Willie Makeit]

Originally Posted by crakarjax

Did you read that and if so could you summarize the findings? At a glance it looks way too dry to keep me awake

I use it pretty much on a daily basis as well as the one listed below. I work for NASA.

Nutshell version of NASA's view on split-type lock washers:

NASA Fastener Design Manual RP-1228 - Page 9-10:

"The lockwasher serves as a spring while the bolt is being tightened. However, the washer is normally flat by the time the bolt is fully torqued. At this time it is equivalent to a solid flat washer, and its locking ability is nonexistent. In summary, a lockwasher of this type is useless for locking."

http://ntrs.nasa.gov/archive/nasa/ca...9900009424.pdf

[crakarjax]

Thanks! What do you guys use then, if anything? I've heard that a properly torqued nut shouldn't come loose but have seen evidence to the contrary. As I understand it, thread locking compounds work by filling in non-contact areas in the thread interface, increasing friction and ensuring that vibration doesn't cause intermediate loss of friction that can result in fastener turnout?

[Willie Makeit]

Depends on application really but for flight-certified hardware (stuff that goes into space ) ALL fasteners have a required torque specification and we then use everything from chemical thread locking compounds, deformed threads (nuts), cross-drilled fasteners & safety wire, mechanically-captive fasteners (specialized inserts) to poly-lock nuts to keep stuff where it's suppose to be. Loose nuts, washers and bolts floating around inside the International Space Station can make for a bad day.

And no, I have never seen a split-type lock washer used as a locking mechanism here.

[special-K]

Originally Posted by crakarjax

Engineering has evolved quite a bit since the late 1800s, and they certainly didn't have the capability of testing the efficacy of these things back then.

https://www.google.com/patents/US514...D2AYkQ6AEIPzAF

How do you know these had no detrimental effect? Did you have side by side nuts and compare the rate at which their tension decreased over time? I'll take empirical evidence over anecdotal every time.

I'll take proof in the pudding. Time has been the test. As you say, the 1800s were a long time ago. I've had nuts kept tight by using lock washers for decades I'm a K.I.S.S. kind of guy, not an engineer. Not dumb, just recognize the beauty of simplicity and find it suits me. I don't feel like reading a bunch of mumbo jumbo. Why don't you just post right here in simple English what the detrimental effects are. Not wanting to make a fuss, just expressing my point of view. Sorry if that is hard to accept. All I know is people have used lock washers all this time and they have kept nuts from backing off. Isn't that all that matters? If I have been experiencing detrimental effects, I sure can't tell. Slipped right by me, so must not matter. That's what I meant by "moot". Real world is where I live, not on a piece of paper. Did it take since the 1800s to figure this out or was there no reason to question? I'm not flying an airplane or into space travel. Everything is crucial there. Just the added weight of lock washers compared to using thread compound is enough cause to go that route.

Clarification: I used the "wrong" wording in my first statement, and that's probably what is causing friction. I would have edited it but it had already been read and responded to. I should have said "prove it doesn't matter" in most practical applications. That is the point I was making. My experience has been they help hold things tighter than without. To what degree I don't know. I also have learned to use thread lock in crucial situations. The stroked 26 year old Harley I've ridden for 13 years (on that engine) has a solid engine mounting. It is a bone shaker. Harley used lock washers throughout, even on things such as switch housings, but no thread lock. The engine cases use lock washers and compound, along with other cases and major mechanical components fasteners. But not everything on the bike. Things hold together well. The problem I have is metal fatigue. The sheet metal wants to split and even had the tab that mounts the belt guard on the swing arm break at the weld. Both fenders have cracks in the flat sides. There was a chrome cover for the rear master cylinder and it split around the bolts. The lower chrome steel belt guard split in half, and I had long low pipes that extended 6" beyond the rear hub. Both pipes were splitting around the diameter just beyond the rear mount, so I cut them shorter. All these fasteners had held tight with no compounds, only lock washers.

[ERASER5]

The data a does not say lock washers make things looser. It says it makes the bolts weakER. ER, as in somewhat, a little, measurable. Not weak as a cat, or loose as a goose. Lock washers are made to gouge, that's why they work. They dig in like studded snow tires. That's good and bad depending what you are doing.

My "made in China" charcoal grill had split washers for every nut and bolt. Yes I used them. A nylock would melt out, a pinch nut would be a royal pain to use, and locking compound melts out. Split washer was the best choice for that application.

[crakarjax]

Originally Posted by ERASER5

My "made in China" charcoal grill had split washers for every nut and bolt. Yes I used them. A nylock would melt out, a pinch nut would be a royal pain to use, and locking compound melts out. Split washer was the best choice for that application.

I think a distorted thread lock nut would work better but they also cost a whole lot more.

[special-K]

Definitely cost a lot more since the lock washers were included in the cost of the grille. How much better than "works just fine" do they need to be? I talked this weekend to a guy in his 80s who runs Model Ts on thousands of mile tours and has done so for many many years. He's driven to Alaska in one, and he says BS. He was an Air Corp pilot in his younger days and is 3rd generation coal mining business. They use lock washers on their equipment and he told be to ask what you guys thought about that.
He's had this one for 60 years. Solid rubber tire with 5th wheel:

[crakarjax]

Originally Posted by special-K

Definitely cost a lot more since the lock washers were included in the cost of the grille.

I was referring to manufacturing cost and took his comment from a design decision standpoint.

Since you know a coal miner that swears by lock washers are you saying we should ignore the "experts" with "evidence" gathered in a "scientific" fashion? Everyone is welcome to their opinion but let's keep this thread fact-based as that's what it was intended to be.

[midniteblues]

Originally Posted by special-K

Definitely cost a lot more since the lock washers were included in the cost of the grille. How much better than "works just fine" do they need to be? I talked this weekend to a guy in his 80s who runs Model Ts on thousands of mile tours and has done so for many many years. He's driven to Alaska in one, and he says BS. He was an Air Corp pilot in his younger days and is 3rd generation coal mining business. They use lock washers on their equipment and he told be to ask what you guys thought about that.
He's had this one for 60 years. Solid rubber tire with 5th wheel:

now that is a cool truck!
idc what brand name it is.... solid rubber for carrying the weight and a 5th wheel ohhhh.
i do have a soft spot for the looks of the very early trucks.

[jmcd]

There's values for every aplilacation. If you dont wantscratch your

There's pros and con for every apilickation .use what you want your not gunna die . This topic is to vague to get into .You never said what you where tightening just worried bout paint?

[special-K]

Originally Posted by crakarjax

I was referring to manufacturing cost and took his comment from a design decision standpoint.

Since you know a coal miner that swears by lock washers are you saying we should ignore the "experts" with "evidence" gathered in a "scientific" fashion? Everyone is welcome to their opinion but let's keep this thread fact-based as that's what it was intended to be.

I'll bow out after this. We all have opinions, but you and I can't seem to relate to each other. You don't seem to be getting my point(s). I do understand yours. We don't live in a laboratory. 100 years of hard daily use in the rigors of a mining operation and driving thousands of miles in primitive cars produces real world facts...where it counts! The fact is, you can stop using lock washers if you want to, but your title says "Don't use lock washers" and that is what I am reacting to. That is yours and some school of engineers' opinion. I'll let my life's experiences be my laboratory, take your "facts" into account, and do what I feel is best for me. And I am sure you won't see me coming back crying that I was wrong. I don't wear blinders. I am a very open minded person willing to change when change is due. But I also keep on keepin' on with what I know don't need no fixin', proven by the test of time and decided upon by myself through deductive and objective evaluation. The good lord gimme a purdy dang good mind and I'll use it as I see fit, thanky

[special-K]

Sorry for the hijack. Just taking a moment to inform

Originally Posted by midniteblues

now that is a cool truck!
idc what brand name it is.... solid rubber for carrying the weight and a 5th wheel ohhhh.
i do have a soft spot for the looks of the very early trucks.

It's a '26 Ford Model TT. The TT came with solidd rubber rear and pneumatic fronts. Pneumatics were new to the world and not trusted to carry but so many pounds, and solids assured the load got there w/o a hitch. The solids were added to the front to better equip the truck for heavier hauling per the fifth wheel. They didn't run to fast back then, but roads were rough and there were no shocks! This one actually had add-ons called Hasslers. They were just coils mounted at an angle side to side, mostly controlled body roll since the transverse springs created that action over bumps. This truck had them front and rear. There were also aftermarket friction shocks.

[Stocker]

Originally Posted by special-K

The TT came with solidd rubber rear and pneumatic fronts.

I see what you didd there!

[Willie Makeit]

next time you're piddling around with a car that was built since the mid 80's, notice how few split washers (if any) are used. technology transfer & research are great things when funded by the American tax-payer.