Removal of Broken Studs and Bolts – Dave’s Garage

We’ve all been there, especially while working on vehicles that are driven in salt. We start to wrench a nut or a bolt, and… SNAP!

sheered boltHere, the fastener is broken off, the metal has been cleaned up and is ready for the weld.

Easy outs can work, unless they twist or snap off. Ever try to drill out an easy- out? It’s almost impossible. The metal is very hard, and when they snap, they usually give no warning. It is also almost impossible to drill and tap without going off center. I have a little trick I’ve been using for years, very handy if you have access to a MIG welder. First, weld a bulb on the end of the broken stud or bolt. The resulting heat from the weld will heat the fastener and usually break the rust bond.

broken stud boltHere, the metal bulb is welded to the end of the broken stud. While the weld is still hot, penetrating oil is sprayed on the broken stud.
Second, either place a nut over the bulb and weld it to the bulb, or latch on to the bulb with a pair of vise grips. If you elected to weld a nut on the bulb, place a box wrench over the nut.

broken bolt vice gripsAfter locking on the bulb with vise grips, the broken stud was coaxed out by gently rocking it back and forth until it easily unscrewed. You can see the shiny steel weld in the jaws of the vise grips, and the rust colored threads of the broken stud.

Soak the fastener with penetrating oil, then gently work it loose by rocking it back and forth. Now it should easily back out. This process is much easier when trying to remove a steel fastener from a non-ferrous metal (brass, bronze, aluminum, etc.) because these materials will not weld with a mig welder, and the weld will not stick to anything but the fastener. I have also welded nuts to rounded off bolt heads and nuts to facilitate their removal.

Remember, when reassembling these parts, use a liberal amount of Never-Seize, so the next time you take it apart, it will come apart.
I hope this tip helps!


Please email all inquiries to: Dave
or snail mail
32 Turkey Hill Road
Richmond VT 05477

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