Wrench Tip: Stop Stripping Screw Heads!

by David Zipf

Say you’re working on your brakes. Your rotors are gouged and worn out and they need to come off. But what’s this? There are those little Phillips screws that hold the rotor to the hub to prevent it from rattling around. And it’s been 40,000 miles since you last pulled the rotors. 40,000 miles of corrosion, heat cycling, and dirt getting have all conspired to fuse those threads so tight that the screw won’t budge. You prepare to set your screwdriver in, sweat beading on your brow as you realize you are now playing Russian Roulette: If you get this wrong, you’ll be spending the next half hour carefully drilling out the head of the screw, yanking the bits free, and then digging around for a bolt in your spares that’s close enough, but not quite right. And then you will have to repeat the process twice for every rotor. This could be a long afternoon…

Living on the East Coast makes every maintenance job an adventure.

But then you remember this wrench tip, and the screw pops free with almost no fuss.

Obviously the first step is to use some penetrating oil. If you don’t own PB Blaster and you’re a gear head, you’re doing it wrong. Not only is this stuff the absolute BEST rust penetrant (I’ve freed decade old brake bleeders that were so frozen the brake fluid bled from the threads, not the bleed nipple), but your car will have the refreshing scent of citrus as you work on it. Spray in a bit of PB blaster and let it sit for a few minutes. Then pass over that screwdriver in your toolbox and grab these tools instead:

You should be worried if you hear the Voltron music at any point during this process

They are, a 3/8” ratchet, a 3/8 to 1/4 socket adapter, a 1/4” socket, and a Phillips head screwdriver bit (or Torx, or flat head, or whatever is appropriate for the screw you’re trying to remove).

Fit all of these together and pop the screw loose. The reason this works is you can apply lots of pressure to the screw head (by pressing on the head of the ratchet) to keep the head from stripping. And with the leverage of the ratchet, you can easily break the threads loose. You can do this with a drill, but because the drill has so much torque you’re likely jump the bit out and strip the head. With the ratchet, you can gradually apply the torque and prevent this.

Finally, a dab of never seize when replacing screws like this will make it much easier to remove them in the future. The stuff is a mess but it really does help.

This also works really well if you’re renovating an old house with screws that are covered in a dozen layers of paint and haven’t been touched in over 70 years. You won't save every screw, but you might just save a few.

Wrench Tip: Stop Stripping Screw Heads!