I just did some safety wiring on my roadster pickup. It has been 53 years since I was up close and personal with every C 124 coming and going through Hawaii. That was 67 to 70. I was amazed I was able to pull off a decent job. While in the Air Force, we were not allowed to use safety wire pliers. The guy inspecting the work would rub a cotton handkerchief over the entire piece. Pliers left little knicks in the wire. If he found a Knick, you redid the work.
My first attempt at safety wiring. It's an early Hilborn BL420 pump. Doing small jobs like this makes me appreciate the skill that aviation guys have. I will get better over time. Some of the stuff I see on modern gas turbines makes me shake my head. It is functional (the bolts won't fall out), but often not correct (not tight enough to prevent slight loosening) and rarely the gracefully laid stuff you see in milspec work. Cheers, Harv
Nothing like the sensation of safety wire under a finger nail! And thank God Curtiss-Wright came up with the sheetmetal lock plates for the cylinder base bolts on a 3350. Prior to that you had to make your own extended duckbills to safety those.
Harv, build a plate and bolt some safety wire bolts on it and just practice. It gets easier with time. It should be 7-10 twists per inch and smooth. Just fold your wire in half, pull it tight, and lay it up next to the hole where it will end. It will shrink a bit, but you will get the idea on about how much that will be. The twists should not go inside the hole on the bolt. Don't over twist. If the twists start to look like they are horizontal rather than at a 45 then it's too tight. When it's about right it will kinda feel like a guitar string, if that makes sense. When you make your pigtail, reverse the direction of the twist, then fold it over so it doesn't stab you.
I went through many rolls of.032 safety wire in the strategic air command in the 60's. Oh to build one more j33 or j60
We used MS20995 wire at work, I recall .020 and .032 for most jobs. We had a section on "how to" in our workmanship standards that was a pretty good guide.
we used safety wire pliers for the 6 months at McChord AFB in Tacoma Wa. They issued us the pliers when we got our tools in Hawaii but we’re told not to use them. It might have just been a local thing at Hickam AFB . Since most of the planes we worked on were transit, I guess they wanted it perfect !!
I had to do a bunch of it in A&P training. Its satisfying when you make a pretty one, but truth be told I (and most people I knew) hated doing it. Its easy to make look passable and be functional, but its hard to make perfect. It can technically be failed for a tool mark. One of those things that if an inspector really wants to go over it with a microscope they can probably manufacture a reason to make you redo it if they want to. Once I was out in the real world most of the aircraft I worked on used SAF-T-Cable. Which is far superior IMO. Doesnt look as cool though.
The tell tale is the beginning and the end. Some of these are loose enough to flop around from the start.
Trying to figure out which direction to run the wire while working overhead... I usually managed to do the first one backwards; redid it correctly and then the rest went ok... Until the next time.
Link to the FAA standard 43.13-1B referred to above... really good info. Start from page 327 for safety wiring. https://www.faa.gov/documentLibrary/media/Advisory_Circular/AC_43.13-1B_w-chg1.pdf Cheers Harv
I used to have to do a ton of turnbuckles. They are a totally different subject, another art in itself. Thank God for clips.
Here's how I handle steering joints. I'm not trying to win style points in this application, I'm trying to ensure the thing stays together. This joint has about 60,000 miles on it in my Willys. Yes that's a R&P on that axle- the horror! I had a cruel task master in the Military. He had me wire up a hub full of bolts in a jet engine. He looked at my hour's worth of wiring and said, "Too lose!"- and proceeded to dyke the middle of each run. He said, "do it again, you need the practice." Well, he was right. I do hate doing it though, especially in confined spaces.
If i had a nickel for every tie wrap and safety wire i have done with years in service and 30 years with Mcdonnell aircraft, later Boeing, i would not need to win the lottery.
Safety wire was something I really enjoyed while working at the Lazy B. Once you figured out the correct lengths, tautness, twists per inch, how to flip your wrist at the right time and direction to make it lay properly. Doing the 747 flap drive torque tube screws in sequence in the rear spar by mirror and flashlight was kind of challenging. The talent pool has become so depleted I've been told safety cable is allowable. No talent required.
Just remembering that I learned to do safety wire at Boeings in 1966. I don't think that I ever did it on a plane in the plant but did some later on a car or two.
The Jalopy Journal
