Brake Disc Set Screws Need to Just Stop Being a Thing

Every so often, I dabble in some mechanic work in my garage. Mostly, I spend my time banging on things and cussing a lot with not much actually getting done and a few things getting broken. But, no matter what car I work on, Set Screws on brake discs are a constant pain.

Just to be clear, the set screw is on the brake disc that holds it in place. However, while the caliper is off and before surface rust bonds the two components anyway.

I hate everything about them. I am in the camp of people who wholeheartedly believes they are completely unnecessary. Set screws are put on during manufacture to keep the disc in place on the assembly line. However, once the car rolls off the line, they are completely useless.

Just to be clear, the set screw is on the brake disc to hold it in place. Only while the caliper is off and before surface rust bonds the two components anyway.

People will say the screw is necessary for the brake disc to stay in place while the vehicle is moving. The caliper will do that unless something is horribly wrong.

Andy, why do you hate brake set screws so much?

Last night, I decided (the car really decided by whaling until I couldn’t stand it) to replace the pads, discs, and sensors on my wife’s SUV. All is going slicker than snot until I go to take the set screw

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out. I had anticipated troubles before so I pre-prepped by soaking the set screws with penetrating oil. They soaked for about an hour while I stared at them menacingly hoping a death stare would shrink them into submission.

I went to work on them with my Hex Key and nothing. Tried it with an L Hex and a breaker bar, still no motion. Kicked the disc then went back to work. A different approach this time though. A punch and a hammer to tap it around. Nada. In the end, I had to drill them out.

I had to drill out a non-essential part to change the most essential part of the car.

What else can manufacturers do?

I understand the need to keep the disc in place before the wheel and caliper are installed. However, I have a solution.

Rare earth magnets.

A penny-sized magnet on the hub, and another on the disc. Whole problem solved. No drilling, no tapping, much less cursing and a strategic tap from a hammer and the old disc will pop right off.

Next: Raising auto tariffs - solution or stalemate?

Engineers can chime in below to tell me why this will never work.

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