Flathead screws only restrict the movement of the screwdriver in one dimension and allow it to move in the other one. This leads to the screwdriver to keep sliding out when you put force on under even the slightest angle.
Phillips screws improve on this design by restricting movement in two dimensions and force the screwdriver to always be in the center, but they slip easily and wear quickly.
Torx are superior because they fit much more "snugly", though at the (minor) cost of being less forgiving of using the wrong size of screwdriver.
The drill will bite into the screw and start unscrewing it
It would probably even cause a measurable increase in lifespan due to removal of a significant stress source. But I can dream...
Hence: Kill on sight.
Came here to say the exact same thing. Rusty flatheads, ah, such joy. Literally lost hours because of it.
To make them work even better you can burnish a slight edge one the blade which will dig in and stop slippage.
It's not cheap ones; Phillips heads were designed to strip out. It's the very reason they're used.
The whole idea was to use them in factory assembly, so that workers wouldn't overtorque them. You put them in and tighten, and when they cam out, you're done.
If you want a fastener that can be easily removed, and maybe reused several times, Phillips is the wrong choice.
And if you have a torque-limiting screwdriver, as should be common in any modern factory, then Phillips is simply obsolete and unnecessary.
I've had Phillips over-torque and eat threads. I've had them strip to a raw steel crater long before the head even meets the surface it's being screwed into.
Definitely agree that Phillips is obsolete. God I hate them. I may have a problem. I've worked on a lot of old engines in my life and seeing a torn-out cross is like a big middle finger from the previous person who worked on it, usually the manufacturer. An engine is something that deserves an easily removed fastener that is applied with a torque wrench. Who knows how many newton-meters a Phillips head takes before it cams? Does anybody? Probably a huge range.
>Who knows how many newton-meters a Phillips head takes before it cams? Does anybody? Probably a huge range.
Yep, that's the problem with them. Maybe they made sense decades ago when assembling aluminum aircraft and they didn't have widely-available torque-limiting screwdrivers. But now they're ridiculously obsolete, and the only reason we still use them is because of sheer inertia (i.e., everyone has a Phillips-head screwdriver handy, but lots of people do not have a set of Torx drivers at hand; also, the inertia makes them cheap). They should have been retired ages ago. If I were dictator, I'd simply ban them (not allowed in new designs, no new Phillips screws allowed to be sold, but drivers of course are fine for removing old ones to replace with better fasteners). There is simply no good reason to use Phillips now.
<I'll see myself out.>
A good flat head screw is better than a crappy Phillips but a bad one is worse. The bad ones seem to strip by design.
You don't really remove pocket hole screws much (though you certainly can with much less cam-out than Phillips head) so it's optimizing for the presumed one-way trip. I would assume anyway.
Almost every time I remove a pocket hole screw it's because I'm trimming something glued up (like a table top) and didn't plan for the saw blade when I put in the screws. Every time I think "heehaaw" and then I do it again the next time.
Just to make the point: I've stripped out more torx drivers than I have torx heads.
I can say I truly don't understand how phillips ever even took hold over flatheads. Cheap phillips head screws seem designed to strip out.
Somebody elsewhere in this thread made the point that they are self-centering, and make industrial manufacturing easier. I guess that makes sense.