The Truth - Which Holds Better? Split Lock Washer, Internal Tooth Lock Washer, or Locknut

Find out which holds better with a stronger hold... split lock washers, internal tooth lock washers, or lock nuts. I tested the three locking devices and share what I found.
@hacksbydad

This video is for entertainment purposes only. Rely on the information in this video at your own risk.

[nickp]

Hello, you did a nice job with the experiment. However, the premise of the experiment is flawed. Lock washers/nuts are not intended to resist loosening torque. They are intended to resist vibrations. A better test would be to repeat what you did, and then place the entire test setup on a vibratory table. See how many minutes/hours/days it takes for each type to loosen.

[PaulHenreid]

Fascinating and important test - thank you! At least the nylon locknut serves a purpose (even if not at the initial loosening).

[WorldravenNevar]

Uhhh... Isn't the point of lock washers and lock nuts to prevent loosening from vibration? What is the purpose of this test?

[mmorgz]

The loss of preload was most likely due to the washers or nut/bolt shaving away with the vibrations. You could counteract this with using Conical spring washers with the nylocks.
I always reach for cone lock or nylocks where there is vibrations or movement.

[jessicavotran]

Good effort but not using vibration test defeats the purpose of locking strength

[rawbacon]

I've read test where the tooth washers helped (although those may have been external) but certainly not what happened here. The rest wasn't really a surprise, the obvious reason I like Nylon Nuts (Nyloc) is what you showed here, even if they do loosen they can't just vibrate off the rest of the way.

[AwestrikeFearofGods]

It was smart to consider the weight of the scale. Don't forget that the torque wrench also has weight that applies a torque. This torque should be added to each measurement of applied torque. While true that the weight of the wrench applies both while tightening and loosening, it would be a mistake to ignore it. For example, if the torque wrench were much heavier, then its weight alone would apply enough torque to tighten and loosen the nuts.

To make the measurements even more accurate, the direction of applied force should be very close to 90 degrees from the torque wrench, instead of vertically. This angle is a larger source of error than there would be from wrench's and scale's weights no longer being parallel to the applied force. If you can somehow adjust the rotation of the nuts/bolts to orient the torque wrench horizontally, then the applied force and weight can both be be vertical. Otherwise, the deviation angle for hexagonal nuts would randomly vary between -30 to +30 degrees.

[LugnutsK]

I wonder if the lock features would allow you to apply more torque when screwing in the bolts

[balicrimechannel]

Thanks for taking the time and effort to do this. I'm restoring a classic car and I'm constantly having to decide what nut/ washer combo I should use for various applications. What I'd really like to see is this same test but using the same vibration method you used for the internal toothed washer video you made. I'd particularly like to see the difference between the split washer and the nylon lock nuts.

[stevetx]

Thanks for the very helpful information. I have pedestals for the seats on my aluminum jon boat and I am having trouble keeping the base of the pedestals tight against the sheet metal benches. I have the pedestals attached to the sheet metal benches with toggle/molly bolts. When I am on the lake and suddenly my seat wobbles, it is a bit unnerving. The pedestals loosen while boating. I'm impressed with your very engineering-type approach to your study.

[denverkirk]

I appreciate the attention to detail, great video!

[Nomed]

I thought I knew some things about tools until I watch a video from Hacks By Dad then I realized I know very little. Thanks for all you give us Dad.

[theotheleo]

Locknuts are used to mitigate the loosening of fasteners due to vibration. They bite into the fastener to help hold it in place. So, this isn't a good test of the locknuts' purpose.

[mrtwister]

Yeah, good content. I would say as thorough as ProjectFarms content. Keep up the good work!

[nateb]

Nice work! I would've loved to see blue loc-tite included. Also, if there was some sort of vibration stress over various time periods and what it takes to remove nuts after that.
Im surprised the split washer results but the test doesn't show what they do without giving the regular nut a chance to wiggle free.
Easy to armchair quarterback, cool vid though! If you ever re-shoot, adding the vibration or dynamic movement variable would give better real life results

[e.hernandez]

SPRING WASHER ACTS AS SHOCK ABSORBERS IN A MOVING CAR SLOWDOWN VIBRATIONS. I'M RIGHT?

[VECORlt]

None, the only ones that holds is Nord-lock.

[windwardpro]

Why did you use them against a nut? That's not how they will be used!

[simoncapizzi]

What is the point of this test? You didn't test what the lock washers were designed for (vibration)

[darin]

This is not providing the accurate results that you’re seeking. It’s really all about vibration.