Reuse locknuts?

[johncanfield]

This might seem like an odd question but I'm curious to know if the nylon (or whatever the material is) locknuts lose their effectiveness on reuse. I have an application (a ham antenna) where I made some assembly mistakes and had to remove several stainless steel fasteners and I thought it would be better to use new locknuts (which I did). It would be really, really bad if an antenna fastener becomes loose. Now I have six or eight used locknuts and I'm sure they would be fine for almost all applications.

This is more of an esoteric question but I wonder if anybody else has researched this topic.

[Auguste]

I look inside to see if the nylon is still in good shape and not worn or damaged

I have reused nylon lock nuts . . . but never for a critical operation like your antenna or something that vibrates like on my tractor . . . I keep the used lock nuts in a mason jar

I think you made the right decisions

[jgayman]

If it's a critical application for something that doesn't need routine disassembly I will use new Nylock nuts. In other applications I will reuse them as long as there is noticeable drag from the lock portion during reassembly.

I found this on-line:

Reuse

Authorities disagree on whether nyloc nuts should be reused. For example, Carroll Smith (Carroll Smith's Nuts, Bolts, Fasteners, and Plumbing Handbook) notes that the nylon insert is not damaged by installation and therefore they can be reused many times,^[1] and a Federal Aviation Administration Advisory Circular allows nuts to be reused if the prevailing torque is within specification.^[3] However, an Air Force Technical Order requires replacement of self-locking nuts in critical areas.^[4] Various specifications for aerospace-grade self-locking nuts require that the running torque be maintained after a number of cycles of assembly, but without preloading the fastener.^[5]

[Plug Ugly]

I like to use nylocks and will resuse them in most cases. If they thread on with the same or similar resistance to new ones, they are most likely doing the job they were designed for. If I'm a little skeptical if that's enough to hold it solid, I might put a dab of blue loctite on it. If it's really critical, like holding the axle in my motorcycle, I safety wire it.

[arlen]

This might seem like an odd question but I'm curious to know if the nylon (or whatever the material is) locknuts lose their effectiveness on reuse. I have an application (a ham antenna) where I made some assembly mistakes and had to remove several stainless steel fasteners and I thought it would be better to use new locknuts (which I did). It would be really, really bad if an antenna fastener becomes loose. Now I have six or eight used locknuts and I'm sure they would be fine for almost all applications.

This is more of an esoteric question but I wonder if anybody else has researched this topic.

What kind of ham antenna are you building?

[johncanfield]

What kind of ham antenna are you building?

Its a SteppIR DB18E that’s going on my new Tashjian LM-354 HDSP telescoping tower . The antenna is fairly expensive (and complex) - I’m pretty anal about assembling it properly and not taking any chances.

And thank you everyone for the informative comments! I think I made a good decision and learned something here.

[trboxman]

I'll reuse them 3 times at most.

[SRG]

Its a SteppIR DB18E that’s going on my new Tashjian LM-354 HDSP telescoping tower . The antenna is fairly expensive (and complex) - I’m pretty anal about assembling it properly and not taking any chances.

And thank you everyone for the informative comments! I think I made a good decision and learned something here.

Guy i know put a telescoping HAM antenna on the back of his Jeep Cherokee. it was all machined very nicely, and quite expensive. He claimed it was built so stout that he wasn't worried about it being hit by tree branches when we would go off-roading and he proved it, and it took a beating pretty well. It was like a 5-6" tube, and like 3-4' collapsed and I believe it extended out to almost double that. It was the oddest looking thing on the back of a Jeep He said some guy off some HAM forum (or something) makes them individually to order.

Oh, I reuse lock nuts too, as long as I can't thread them on by hand.

EDIT; Hot damn, I found a pic from a couple years ago on a wheeling trip (green Cherokee in the middle, can make out the tube antenna on the rear bumper).....

[johncanfield]

I see that antenna, bully for him! We also are (were actually) into rock crawling with our highly modified Jeep Rubicon on 37” tires.

[Zebrafive]

Guy i know put a telescoping HAM antenna on the back of his Jeep Cherokee. it was all machined very nicely, and quite expensive. He claimed it was built so stout that he wasn't worried about it being hit by tree branches when we would go off-roading and he proved it, and it took a beating pretty well. It was like a 5-6" tube, and like 3-4' collapsed and I believe it extended out to almost double that. It was the oddest looking thing on the back of a Jeep He said some guy off some HAM forum (or something) makes them individually to order.

Oh, I reuse lock nuts too, as long as I can't thread them on by hand.

EDIT; Hot damn, I found a pic from a couple years ago on a wheeling trip (green Cherokee in the middle, can make out the tube antenna on the rear bumper).....

Is that Silver Lake State park?