How to Safety-Wire - Play It Safe!

These four examples apply to all bolts, fillister-head screws, square-head plugs, and other similar parts which are wired so that that loosening tendency of either part is counteracted by tightening of the other. The direction of twist from the second to the third unit is counterclockwise in examples one, three, and four to keep the loop in position against the head of the bolt. The direction of twist from the second to the third unit in example two is clockwise to keep the wire in position around the second unit. The wire entering the hole in the third unit will be the lower wire, except in example two, and by making a counterclockwise twist after it leaves the hole, the loop will be secured in place around the head of that fastener.

These four examples show methods for wiring various standard items. Note that the wire may be wrapped over the unit rather than around it when wiring castellated nuts or on other items when there is a clearance problem.

When wiring bolts in different planes, the wire should always be applied so that tension is in the tightening direction.

Shown is the correct application of single wire to closely spaced multiple group fasteners.

Fittings incorporating wire lugs shall be wired as shown.

Hollow-head plugs shall be wired as shown with the tab bent inside the hole to avoid snags and possible injury.

Where no lock-wire lug is provided, wire should be applied as shown with caution being exerted that the wire is tightly wrapped around the fitting.

Small size coupling nuts shall be wired by wrapping the wire around the nut and inserting it through the holes as shown.

Coupling nuts attached to straight connectors shall be wired as shown, when hex is an integral part of the connector.

I decided to try my hand at "safetying," as it's known in the aircraft industry, on a blower pop-off plate I had laying around. I chose this object for no other reason than it had a number of fasteners in a circular pattern to practice on.

The first step was to drill the heads of the Allen fasteners using the Graham Tool drill jig.