Posi screws in your Square

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WesN

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You might find a lot of philips screws in your GM truck have been rounded out or your screw driver slips while you are removing or tightening them. That is because they are not Philips they are Posidrive. It is easy to spot because of the little dots between the x on the screw (see photo) if you look at the two screw driver blades you will see at the part that enters the screw the Posi is rounded and the Philips is straight edged. The Posi drive will actually hold a Posi screw horizontal without being magnetic. Believe it or not I have taught a number of Snap-on and Mac dealers about this because they weren’t aware of it.
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DoubleDingo

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I've seen drivers with that tip but never knew it was special, thought it was just different. I learned something today, now I can go home.
 

MikeB

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Back in the day, Hewlett Packard and others used Pozidriv screws on electronic test equipment that I worked with. Using them and the proper screwdriver makes you wonder why they aren't more popular. Pozidriv is to Phillips, as Phillips is to straight slot.
 
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Salty Crusty

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One is true phillips, the other was first called Reed and Prince (I think it's your posi drive). The depth of the pointed tip was considered wasted since it provided no meaningful surface area on which to imart force.
 

eskimomann209

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I too learned something today... never knew that.

I still say Robertson screws are better. ;)
I used a lot of Robertson screws doing hardi backer cement board and other sub flooring stuff. I thought I loved those, then everyone went t25 Torx. I’ll admit for construction screws they’re the ****. I adore them, they also put a little flute on the tip of the screws to help cut better. Makes subfloor repair in older homes way easier.
 

DoubleDingo

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Carb'ed Vortec 350; 1972 L48 350
I used a lot of Robertson screws doing hardi backer cement board and other sub flooring stuff. I thought I loved those, then everyone went t25 Torx. I’ll admit for construction screws they’re the ****. I adore them, they also put a little flute on the tip of the screws to help cut better. Makes subfloor repair in older homes way easier.

Oh yeah those torx screws are the bees-knees
 

Goldie Driver

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You might find a lot of philips screws in your GM truck have been rounded out or your screw driver slips while you are removing or tightening them. That is because they are not Philips they are Posidrive. It is easy to spot because of the little dots between the x on the screw (see photo) if you look at the two screw driver blades you will see at the part that enters the screw the Posi is rounded and the Philips is straight edged. The Posi drive will actually hold a Posi screw horizontal without being magnetic. Believe it or not I have taught a number of Snap-on and Mac dealers about this because they weren’t aware of it.
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Cool to know, but now I guess I need more tools.

Ever heard anything about Japanese Phillips?

I wonder if they are really some sort of a Posi style.
 

Turbo4whl

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The Amish builders in this area have been using Robertson screws for years. Electric power tools are not recommended in their lifestyle, air tools, fully acceptable.

Yeah, Pozidriv, mine says USA :patriot:

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AuroraGirl

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square screws... about 3 of my tail light screws were square, 4 were torx, 3 were standard, 2 were hex, and the rest were phillips!

I went and bought new U clips, used #8 1 inch phillips screws with anti sneeze.
Why, grandpa.
 
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square screws... about 3 of my tail light screws were square, 4 were torx, 3 were standard, 2 were hex, and the rest were phillips!

I went and bought new U clips, used #8 1 inch phillips screws with anti sneeze.
Why, grandpa.
Anti sneeze? just kidding
 

MikeB

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One is true phillips, the other was first called Reed and Prince (I think it's your posi drive). The depth of the pointed tip was considered wasted since it provided no meaningful surface area on which to imart force.
Reed and Prince screwdrivers have a point. Can't think of anything the screws were good for.

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DoubleDingo

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Carb'ed Vortec 350; 1972 L48 350
...................Can't think of anything the screws were good for.

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Getting stripped out by guys like me that didn't know these types of screws existed?
 

WFO

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There's also JIS (Japanese Industrial Standard) screws.
 

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