Fun with safety wire

Timbeck2 said:
I do. That second from the top bolt gives me the heebie geebies. It is neutral and was wired better when it was single strand. Just sayin. ;)

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Not to be super critical like everyone else but the purpose of the pigtail is to tuck and place the cut end of the wire against the bolt head so as to make it near impossible to rip your friggin' finger open and bleed all over the component.
 
Silvaire said:
Not to be super critical like everyone else but the purpose of the pigtail is to tuck and place the cut end of the wire against the bolt head so as to make it near impossible to rip your friggin' finger open and bleed all over the component.
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Obviously doesn't work:D
 
fiveoboy01 said:
Obviously doesn't work:D
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A lot of people don't do it "right" and many of the pictured examples you see don't show it "right" and in Eddie's example it doesn't much matter but for many applications where the component might in a place that you might be groping around or reaching past for some other reason it's nice to be able to pull your arm out without creating a seven inch bleeding gash along it ;)

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Silvaire said:
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Now in this example of safety wiring, to me the lower left bolt could be released by simply lifting the double strand over the top of the bolt head, something that could be done with your fingers.

To me, if I was confronted with that wire hole combination, I'd go for the opposite direction/side and a wire over the top of the head. Admittedly not a very good situation (better to find another bolt), and safety wire is really only to keep the bolt around for accident investigators.

Of course if a properly tightened bolt is determined to work its way loose, safety wire or Palnuts ain't gonna stop it from falling off - wood props excepted.
 
I got the "It could work, but we would not want other shops to think we did that" "Redo it" Clamping forceps seem to help. Also using really long pieces of wire seems to help with the pin cushion blood donation.
 
nrpetersen said:
Now in this example of safety wiring, to me the lower left bolt could be released by simply lifting the double strand over the top of the bolt head, something that could be done with your fingers.

To me, if I was confronted with that wire hole combination, I'd go for the opposite direction/side and a wire over the top of the head. Admittedly not a very good situation (better to find another bolt), and safety wire is really only to keep the bolt around for accident investigators.

Of course if a properly tightened bolt is determined to work its way loose, safety wire or Palnuts ain't gonna stop it from falling off - wood props excepted.
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If it's pulled properly tight you're gonna need a small pry bar. You ain't going to move it with your finger.
 
nrpetersen said:
...Of course if a properly tightened bolt is determined to work its way loose, safety wire or Palnuts ain't gonna stop it from falling off ...
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There's no way a safety wired bolt like that is going to "fall off" it's just not possible unless the safety wire is broken by some other outside force.
 
nrpetersen said:
Of course if a properly tightened bolt is determined to work its way loose, safety wire or Palnuts ain't gonna stop it from falling off - wood props excepted.
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Au contraire. That is precisely what safety wire is designed to do. Prevent initial movement/de-tensioning of a properly installed/tightened fastener. That is why it's so important it's done right, tight, not sloppy. It's one of the most important tasks that A&P's do all the time and many don't take pride in it.
 
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Let's not forget .....anyone can replace safety wire. :eek:

14CFR 43.13 Appendix A to Part 43 (c) Preventive maintenance.
.....
(5) Replacing defective safety wiring or cotter keys.
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I may not know much about ammeters and such but safety wire I know. Ten years working on military jet engines from a trainee to QA (QC) will get one pretty good at it.
 
Timbeck2 said:
I do. That second from the top bolt gives me the heebie geebies. It is neutral and was wired better when it was single strand. Just sayin. ;)
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Yup. That bolt can turn considerably as the wire slides through the hole in the bolt head. The wire should have gone around the outside of the bolt head, and the twist should be right up against the hole where the two come together, like he has it on that bottom bolt.
 
Checkout_my_Six said:
Let's not forget .....anyone can replace safety wire. :eek:
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True but let me ask this. If you find safety wire broken, can you be assured that the fastener is still properly torqued? If not and the affected fastener is not on a component that falls under preventive maintenance, what does the pilot-owner do?
 
SkyDog58 said:
True but let me ask this. If you find safety wire broken, can you be assured that the fastener is still properly torqued? If not and the affected fastener is not on a component that falls under preventive maintenance, what does the pilot-owner do?
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I have cross-check applied to every fastener that is critical. If it moves, safety wired or not, I'll know it. Wire could possibly break due to vibration, and the fastener could still be torqued correctly.
 
I built a couple of jet engine test cells for the Navy in the 80s. The contracting officer sent me over to a maintenance hanger to learn safety wire techniques from a DynCorp mechanic so I could inspect and certify the safety wiring being done in the test cell.

For example, the bulletproof glass in the control cubicle window was held in place by 1 1/2" angle attached to the steel channel frame by 3/8" bolts on 3" centers. We had to use .041 wire. I seem to recall that no more than three bolts could be tied together by one length of wire. The window was about 6' X 4', there were a lot of bolts to wire.

It was pretty cool to see a F110-GE-400 chained down in the cell and running at full AB.
 
I was one of the first mechanics trained on the tear down, build up and test cell of the first generation of the F-110. I made a lot of money (to me at the time as an E-4) by the suggestion program. A lot of procedures in the Tech Order were written because of my suggestions.

I later went on to spend 5 years working at the test cell in the enclosures similar to what you described. J-79 (F-4), J-85 (T-38) PW F-100 and 220 (F-15 and F-16) and TF-34 (A-10)

Then the Air Force decided they had too many mechanics and we would either volunteer or risk being volun-told to cross-train into something else. So that's how Timmy became an Air Traffic Controller.
 
I will admit, I enjoyed working on F-4, T-38, and G-1's so you're probably right. It sucks when everything is way up there, or weighs a ton.
 
Here is a cheater technique I was taught by my review instructor for my A&P oral / practical. To tighten up the beginning after you've twisted all the way to the next bolt with the pliers, make wide circles. Hold the pliers in your hand and make a circle. Kind of much easier to show than it is to describe but what that will do is tighten up the very beginning of the wrap near the first bolt head (edit - you probably want to rotate the pliers 360 degrees for each wide turn you make. Should only take one or at most two turns.)
 
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GlennAB1 said:
Looks pretty good, just a little loose. The more you do the better you should get. Master safety wiring by hand, first, that'll make a man out of ya!!!
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Yeah, we were required at school to do all our safety wiring by hand in the first class that covered it.
 
How many of you have safety wired bolts using a steel rod with two angled opposing holes drilled into the end of it? In other words, you can't get safety wire pliers or your hands close enough to do it any other way.
 
You can buy one of the screwdriver-looking dealio's at Spruce...they can come in real handy.
 
Chip Sylverne said:
You can buy one of the screwdriver-looking dealio's at Spruce...they can come in real handy.
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Dang, I just made an order from Spruce two days ago. I'll grab one of these on my next order, thanks.

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alfadog said:
Here is a cheater technique I was taught by my review instructor for my A&P oral / practical. To tighten up the beginning after you've twisted all the way to the next bolt with the pliers, make wide circles. Hold the pliers in your hand and make a circle. Kind of much easier to show than it is to describe but what that will do is tighten up the very beginning of the wrap near the first bolt head (edit - you probably want to rotate the pliers 360 degrees for each wide turn you make. Should only take one or at most two turns.)
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I actually saw a guy doing this in a youtube video. He runs the wire through the first bolt head, twists it, then makes a quick turn of the entire pliers, and almost appears to twist it one more turn all that the same time. I had to watch it several times and I still couldn't figure out what he was doing or why. I am pretty sure he's doing what you describe above. I'll have to watch the video again and definitely try it out. Thanks for the tip:yes:
 
Timbeck2 said:
Then the Air Force decided they had too many mechanics and we would either volunteer or risk being volun-told to cross-train into something else. So that's how Timmy became an Air Traffic Controller.
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POMO (Production Oriented Maintenance Organization) about 1979 they cross-trained Instruments and Autopilot, I was working T-38's, one heck of an autopilot system. LoL.
 
fiveoboy01 said:
I actually saw a guy doing this in a youtube video. He runs the wire through the first bolt head, twists it, then makes a quick turn of the entire pliers, and almost appears to twist it one more turn all that the same time. I had to watch it several times and I still couldn't figure out what he was doing or why. I am pretty sure he's doing what you describe above. I'll have to watch the video again and definitely try it out. Thanks for the tip:yes:
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That's called giving it a woop-tee-do, and it kinda sinches it down, or snugs it up. ;). Got to be careful of overdoing it, don't want to over work (work harden) the wire.
 
Here is a guy doing some on YT. I am not nearly as experienced as JayZ, and maybe I am doing it wrong but I like to get mine really tight from the start. I am pulling on the wire pair from the first time they pass through the bolt head until all twisting is done where able. Then, I like to pluck the end result with my fingernail and ensure it has a twang....or at least no slop. He also is doing.. I think he said 8-10 twists per inch but maybe things are different in Canada. Fun to watch others do it anyway.

https://youtu.be/OwFjUX6SaY8?t=5m42s
how do you get an embedded vid to start at a certain time, mine all stall out:


 
I watched that video too. It was very helpful to me.

Anyways the new prop bolts came and I have them torqued and wired again. I feel like this is a better result. Wire is more snug against the bolt flats, and the wire between the bolts is definitely snug:
 

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Quite beautiful.
I try to maintain the same 6-8 twists per inch on the tail, not sure it's necessary and I note JayZ makes the tail tighter for some reason too.
Also, I try to tuck the sharp edge underneath.
 
Also to add on the tail... I have seen it recommended to twist the tail tighter so that when you loop it, it's less likely to unwind a little. I'm not sure how correct that is, but it makes sense to my mind:lol:
 
Let'sgoflying! said:
Just tell him at the start that if it isn't up to snuff, "he is free to re-do it" -that will kill a lot of excessive persnicketiness!
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Haha!! Well I want to make sure it's done right.. But if it's not sufficient, I'd rather re-do it myself. Of course, I've already wired a pair of the old bolts about 10 times... so I hope I don't have to re-do these:D
 
2015 and we're still using safety wire. Why has no one come up with a less laborious process? I get that it works and there will be a chorus of why change what works, but...

... it's labor intensive, so it's very costly, and,

... it requires considerable knowledge and skill to get right.

Love getting my hands dirty and acquiring the skill. Work of beauty when it's done right. But it just makes our planes more expensive. No safety wire on cars, and there is no epidemic of bolts falling out. Instead, they use cotter pins, staked nuts, nylocks, and other positive retention tools. Why don't we see those in aviation? They're cheap and easy to get right and inspect that they're right.
 
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