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I am trying to remove some screws with some very annoying heads. The screws look like a regular Phillips head but have the center rounded out. This makes a normal Phillps head screwdriver slip as if the screw was already stripped.

I am looking for the correct bit to remove this, as I would like to reuse the screws later. That failing, has anyone had success removing screws with similar "pre-stripped" heads?

I have included an additional photo of another screw "as delivered." This close up shows the center of the head is square, with facets inside the square part of the head. For added context, every screw on the piece of furniture in question has the same head. If it is the result of stripping, the manufacturer was very thorough.

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  • General tips: These can both probably be removed with a common #2 Phillips and some well-aligned force, if that's what you have on hand. Then, they were both probably damaged by a #1 Phillips, that bane of households which is rarely appropriate. 90% of the time folks misuse them on what are actually #2 screws.
    – isherwood
    Apr 15 at 12:47
  • Ah, yup, that new picture definitely indicates both are square drive/quadrex.
    – FreeMan
    Apr 15 at 14:12
  • "If it is the result of stripping, the manufacturer was very thorough." I wouldn't put it past 'em! :D
    – FreeMan
    Apr 15 at 14:13
  • Wikipedia has an impressive list of "screw drives". Apr 15 at 14:50
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    @FreeMan "consistency is key"
    – ajheck
    Apr 15 at 15:27
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The top looks like a Pozidrive or Supadrive and the bottom looks like a Quadrex to me.

If those don't work, you can always cut a flat blade slot for a protruding screw and remove it that way. If that doesn't work, particularly for the top screw which looks actually stripped, get a screw extractor and take it out that way. Always try first without drilling and if you drill be careful not to cut the head off the shaft. For one stripped screw I absolutely could not afford to break, I stopped trying to turn it before it was stripped bald and used PL4OO to glue my screwdriver into the screw.

If you don't need to free the hole, if a screw is soft enough to strip, it's soft enough to drill the head off. For large lag bolt type screws, you can even drill a pilot hole and reclaim the hole by drilling the screw out with increasing sized bits, but these are extremely likely to come out with a screw remover.

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    I changed the link from Quora directly to the Wiki article that answer linked to. Much more info in the Wiki article on the screw heads you mentioned and others in general. I also linked directly to the heads noted.
    – FreeMan
    Apr 15 at 11:51
  • Got to admit, thought, the top one just looks like a plain old stripped out Phillips.
    – FreeMan
    Apr 15 at 11:55
  • @FreeMan There is a polishedness to the bottom of the square part that makes me think it's machined that way, but agree it could be.
    – K H
    Apr 15 at 11:57
  • My vote: top one is a stripped Phillips and bottom is a Quadrex.
    – jay613
    Apr 15 at 13:31
  • The new picture definitely indicates that both are square drive/quadrex
    – FreeMan
    Apr 15 at 14:12
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First guess would be Quadrex. A square drive bit should do the trick.

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