Slotless screwdriver needed...anyone have one?

[Paul Dobbin]

I guess the "Robertson" is a Canadian Phillips.  I buy Canadian square drive screws and find them much better than Phillips.  Never round one out or wear out the square drive bit.  (Not correct on any vehicles that I know of, but great for other projects)

[padgett]

That looks like two different screw heads, one square and one with points. Which is the Robertson ? The square drive ?

[Chris Bamford]

35 minutes ago, padgett said:

That looks like two different screw heads, one square and one with points. Which is the Robertson ? The square drive ?

They are all #2 Robertson square drive. This size screwdriver typically has a red handle. The smaller #1 driver is green, #3 is black. 

 

The screw with the slightly bigger head is a #10 size screw, the others are #8 size screws. It is a trick of the photo that some look like pointed drives -- none, in fact, are. The bottom of the square hole is not flat  (for manufacturing, not for function) which adds to the illusion. 

[Ivan Saxton]

That screw does not look to be self-drilling;  if so it would need a pilot hole unless used on fairly soft material.   What I would look for or make would be something on the principal of those eccentric roller type stud removers, with roller ends protruding slightly beyond the end of the barrel that contains them.  That might be fine to secure your matting as shown.  Taking them out would be difficult without damaging the head circumference by tight end-grip of what I think you call "vyce grips", but which here in Australia are always referred to as   "--gger-nuts",(because that is what they do).

[trimacar]

OK, thanks for all the responses, many of which were very educational, such as on the Robertson square drive screw.  I either didn't know, or had forgotten, that they were invented quite a while ago. 

 

Just to be clear to everyone, I was joking when I said I bought boxes of the screw first pictured.  This was a defect, found in a box of otherwise normal slotted screws, and I just thought I'd have some fun with it.

 

Slotted screws are becoming rarer by the day.  Slotless (or driven) screws are out there, but this isn't one of them!  Or rather, it is one, but only by accident......

[PFitz]

16 hours ago, Paul Dobbin said:

I guess the "Robertson" is a Canadian Phillips.  I buy Canadian square drive screws and find them much better than Phillips.  Never round one out or wear out the square drive bit.  (Not correct on any vehicles that I know of, but great for other projects)

 

What few people don't realize is that's because the Phillips screws were designed to slip.

 

About 25 years ago, while doing research on a 31 car that someone insisted came with Phillips head trim screws, I called the Phillips Screw Company.  In a conversation with the then Vice President of the company, he said the Phillips screw was invented to "cam out" to prevent the problem of over tightening in assembly line work.

 

That's why when you force a stuck Phillips screw, the screw driver is forced up and out (called "cam-out" by the company). That way, the screws would not crack wood from over tightening. He also said that the first use was in Caddy production. And it's that cam-out ability why the Phillips screws gained more acceptance in mass production then the much earlier designed Roberson screws.

 

But that built-in slippage became a problem with the increasing use of modern "deck screws" in home building. To counter that slippage tendency  the Phillips screw company designed the Phillips 2 special drivers  with tiny ridges in the tip that grip down inside the screw slot. When force is applied the ridges bite into the screw increasing the holding power. The VP sent me some of those new Phillips 2 bits to test. I used them to drive 2-1/2 deck screws when I built the radiant heat, laminated wood floor of the wood working room of my shop. Using a 3/8 butterfly impact gun and one of those special Phillips bits, it drove about 2500 deck screws and never slipped.

 

Paul

Edited July 9, 2017 by PFitz (see edit history)

[emjay]

Pozdriv was developed to eliminate the slip of Phillips, which as I understand it was never adopted in Europe.  There was a time the DIY would curse a Phillips (cross recess) and end up putting a slot in it.  Years ago finding a good Phillips screw driver was difficult and if the screw was at least a bit stubborn, either the screw wore out or the driver worn out, so the slot went in and the screw was replaced with a slotted one.  Now slotted ones are usually tossed and can have damaged slots. 

[Curti]

That's why when you force a stuck Phillips screw, the screw driver is forced up and out (called "cam-out" by the company). That way, the screws would not crack wood from over tightening. He also said that the first use was in Caddy production. And it's that cam-out ability why the Phillips screws gained more acceptance in mass production then the much earlier designed Roberson screws.

 

Do you know what year Cadillac used the Phillips screws?  I believe Chevrolet used them in 1937.

[60FlatTop]

On 7/9/2017 at 6:46 AM, trimacar said:

Just to be clear to everyone, I was joking when I said I bought boxes of the screw first pictured.  This was a defect, found in a box of otherwise normal slotted screws, and I just thought I'd have some fun with it.

 

That is the part I found funniest, the need to explain it. Wanna have more fun? Show someone a picture of a car, a person, a house; any subject. Then listen to them completely ignore the subject and ask you about everything in the background. It is a hoot once you become aware of it.

 

Now, what made me think of that.

Bernie

[trimacar]

Cadillac first used Phillips screws in 1937, soon after other manufacturers started using them...

[trimacar]

I just did the same thing yesterday.  Friend sent me a picture of applying leather to a dash panel, all I could see were all the wires under the dash going hither and yon, and that was my comment!