It seems like every repair job involves at least one stuck bolt. And over the years I’ve learned that brute force isn’t the best bolt removal technique.
Introduction
Here’s my proven approach for removing the most stubborn fasteners without even breaking a sweat.
Tools Required
- Air hammer
- ball peen hammer
- hammer bit
- Propane torch
- Wrench
Materials Required
- Rust penetrant
- Water in a spray bottle
Whether you’re a frequent DIYer or just a homeowner who’s not afraid to try their hand at their own repairs here and there, chances are you will at some point come across a rusty bolt that feels like you’ll need the jaws of life to unscrew. Luckily, you don’t need life’s jaws to loosen stuck bolts. Instead of resorting to cutting off the bolt, you can remove the trickiest of bolts and fasteners with some rust penetrant and these simple steps.
What Is Rust Penetrant?
Rust penetrants contain a solvent to dissolve rust, a lubricant to lower friction, and a surface tension reducer for deep penetration. Homebrews like Coke, kerosene and mineral spirits don’t have all those abilities. Neither do general-purpose lubricants. Those products simply don’t work as well or as fast as rust penetrants. You can find penetrants like Liquid Wrench Penetrating Oil, WD-40 Specialist Rust Release and PB B’laster at your local home centers and auto parts stores.
Project step-by-step (5)
Step 1
Soak the bolts with rust penetrant
Give the stuck bolts a shot of rust penetrant. Soak them for at least 15 minutes before attempting to loosen.
Step 2
Hammer micro-cracks into the rust
If step one fails, hit the bolts with a hammer. Create micro-cracks in the rust with blows from a ball peen hammer or an air hammer and a hammer bit (I get the best results using the latter method). Then apply more rust penetrant and “reshock” the bolt head. Repeat until you can turn the bolt.
Step 3
Incorporate a socket
Try a socket on your air hammer. Apply torque to the adapter with a wrench while you apply air hammer blows. The dual force breaks the bolt loose.
- Pro Tip: I’ve had good luck with an air hammer socket adapter. Slip an impact socket onto the adapter and try to loosen the fastener while pulling the trigger.
Step 4
Heat and cool the bolts
If neither trick works, heat and cool the bolt. The expansion and contraction will open cracks in the rust and allow the penetrant to work. But before you heat it, wash off the rust penetrant (most penetrants are flammable). Next, remove any rubber or plastic parts that heat may damage. Then, heat the bolt head with a propane torch. Aim the flame at the bolt head, not the surrounding metal. Heat for about 15 seconds, but do NOT get it cherry red (overheating damages the bolt’s temper, and you’d have to replace it).
Step 5
Shock the bolts with water
Immediately shock the bolt with water spray and continue spraying until it no longer steams. Once the bolt cools, reapply the rust penetrant and try removing it.
