How often has your race ending catastrophe been the result of a measly piece of loose hardware or similar failure? All too often we hear of disasters caused by some two-bit piece of hardware or simple preventable prep error. At the root of many of these issues is a procedural misstep or forgotten bolt.
Among the best racers and engine builder are perfect prep practices that promote performance, provided you pay attention in class. So enough alliterative humor let’s get to it! You have probably heard of safety wire or “lockwire” and have most definitely seen it while wandering in the pits. Locking fasteners like nylocs, split washers, wavy washers, thread locking compound etc. all have their place in automotive or aviation usage but safety wire trumps them all.
Even if you consider yourself an A and P-trained safety wire guru, take a seat and brush up, our Canadian jet mechanic friend AgentJayZ takes a perfectionist approach to showing us how it’s done — and done right.
Before we talk about the technique lets examine the concept and sense of insurance safety wire offers. While it is common place to “witness mark” hardware after it receives a final torque it is easy to miss, forget, or accidentally mark an un-torqued bolt after looking away due to a distraction. Safety wire is visible re-assurance that the fastener has been checked, and verified, and cannot escape unless the wire fails.
Added benefits of safety wire come into their own when heat is applied — while standard wire is generally 304 stainless and adept to standing up to most harsh environments, Inconel wire can be used for the most extreme high temperature applications. While nyloc hardware melts at the first site of exhaust heat or flame, safety wire stands up to the strain.
A few things worth remembering — cut a piece longer than you think you need, eight to ten twists per inch, use the right tools if you have access to them, wire hardware the correct direction whether it’s right of left hand threads, and not mentioned by Jay but if drilling your own six-point bolt heads for wire, a jig is necessary to do it properly.
It is common to find fasteners drilled through the flats, but ideally the bored hole should run corner to corner — a challenging operation without the right jig. Many aviation hardware sources may offer pre-drilled bolts to save you time.
Safety wire makes for power in numbers — as more bolts are connected the safety net grows, one bolt prevents the loosening of the next and so on. Of course this effect is not without considerable time and effort but what is at stake? Your prized vehicle, engine, and potentially life?
Let’s not dismiss the aesthetic merit of safety wire. In the circles of those in the know — safety wire is mark of pride of craftsmanship, care, and attention to detail. This gearhead bling is purely utilitarian but carries with it a cultural association, one of performance and precision. Learn to safety wire, impress you peers and tech inspectors, raise your standards of prep — you’ll thank yourself in the future.