What is a Robertson head screw?

4.81–4.85. A Robertson screw, also known as a square screw or Scrulox, is a type of screw with a square-shaped socket in the screw head and a corresponding square protrusion on the tool. Both the tool and socket have a slight taper.

What is the purpose of a Robertson screw?

Robertson's screws were superior to slot head screws since the square recess automatically centered the screwdriver, provided more surface area for the driver to press against and reduced the chance of slippage.

Why are Robertson screws better?

The square-head screw was invented by P. I. Robertson, a Canadian, in 1908. It offered a big advantage over the slotted screw head because it was self-centering and not prone to slipping when driven.

Why are there no Robertson screws in America?

Most historians attribute its lack of popularity in the United States to Henry Ford. Having been nearly bankrupted by shady European licensees, Robertson refused to license his invention to Ford. Without a guaranteed supply, Ford turned to the Phillips-head screw, cementing its reign in American industry.

What is the difference between a Robertson and a Phillips screwdriver?

Phillips heads have a cross-shaped tool indent. Hex socket screws require an Allen wrench, while hex screws are entirely hexagonal without an indent for a tool, meaning it needs a wrench or socket wrench. Square indentations are also known as Robertson screw heads and require a special driving tool.

Why is it called a Robertson screwdriver?

The Robertson screwdriver, also known as a square screwdriver, was invented in 1908 by P.L. Robertson, a native Canadian.

What does a Robertson screwdriver look like?

A Robertson screw, also known as a square or Scrulox screw drive, is specified as ANSI Type III Square Center and has a square-shaped socket in the screw head and a square protrusion on the tool. Both the tool and the socket have a slight taper.

When did they start using Robertson screws in furniture?

Robertson Screw

In 1908, square-drive screws were invented by Canadian P. L. Robertson (1879–1951), 28 years before Henry Phillips patented his Phillips head screws, which are also square-drive screws.

Why are flathead screws still used?

Flat head screws are good for wood as they prevent overtightening and thus help prevent stripping.

Why do tri wing screws exist?

The Tri-Wing is a type of screw and screw head. It is sometimes called a triangular slotted screw. It is used as a tamper-resistant screw on various products, typically electronics.

Does the US use Robertson screws?

American furniture, appliance and mobile-home industries use them, but the classic Canadian fastener is still virtually unknown to do-it-yourself home renovators. Home Depot reports Robertson screwdrivers account for less than 5 per cent of sales in the United States.

What countries use Robertson screws?

Although the Robertson screw is most popular in Canada, it is used extensively in boat building because it tends not to slip and damage material, it can be used with one hand, and it is much easier to remove/replace after weathering.

Is Robertson the same as square drive?

Although the terms "square drive" and "Robertson" are often treated as the same in catalogs, the difference (as I understand it) is that Robertson tools and screws have a slight taper to the square recess and the square drive ones do not. Most online sources claim that the tapered design is superior.

Why are Robertson screws popular in Canada?

The Robertson socket head screw soared in popularity. Craftsmen favored it because it was self-centering and could be driven with one hand. Industry came to rely on it for the way it reduced product damage and sped up production.

What screw head is least likely to strip?

A square drive and a Phillips drive offer four points of contact, making them less likely to strip than a slotted screw. Hex and Torx screws both offer six points of contact, reducing the likelihood of stripping compared to Phillips and square drives.

Which screw head is best?

The star head (sometimes known as the branded name Torx) is the best commonly-used screw head on the market. It allows for a huge amount of torque without stripping and it's difficult for the bit to slip out.

Why are there both Phillips and flat head screws?

The reason for the different styles is cost and torque. Phillips screws are self-centering, making powered screwdrivers possible. They're somewhat more expensive to produce than slotted-head. They tend to 'cam-out' easily under torque, making it hard to apply much torque.

Why would you use a slotted screw?

Perhaps the biggest advantage of a screw with a slotted head is its simple design. Thanks to the straight slot going across the whole screw head, they can be fairly easily tightened even in cases when you don't have a screwdriver handy.

What is Philip screw?

Definition of Phillips screwdriver

: a screwdriver that is designed to be used with a type of screw (called a Phillips-head screw) that has a slot in its top that looks like a cross.

What number is a Green Robertson screwdriver?

Task Tools T67811 Robertson Screwdriver Power Insert Bit, Number 1, Green, 6-Inch.

Who invented the Robertson screw head?

Peter L. Robertson was a salesman who spent his spare time conjuring inventions in his workshop. The solution was found by a 27-year old Canadian, Peter L. Robertson.

Why is it called a flat head screwdriver?

It's known as standard because it was the original form of driver head. A flathead would refer to the geometry of a screw head itself, and a flatheaded screw could actually have any type of driving head on it (slotted, Phillips, square, etc.).

What are the 4 different types of screw heads?

Types of Screw Heads/Screw Drives

• Step 1: Slotted. Slotted screws are the simplest type of screw, consisting of a single slot at the head of the screw. ...
• Step 2: Phillips. The Phillips screw, named after Henry F. ...
• Step 3: Square Aka "Robertson" ...
• Step 4: Torx Aka "Star" ...
• 19 Comments.

What is a slot head screwdriver?

A "slotted flat blade screwdriver" is a long standard hand-tool dating back to the 1500s. It has a flat-bladed tip used to turn, fasten or loosen screws and bolts. The flat blade screwdriver is an extremely versatile tool and is used for fasteners of all sizes, providing significant leverage.

How do I know what screwdriver bit to use?

Choose the bit size that fills the screw head entirely. A bit that is too big or too small will not seat properly, and you'll end up with a stripped screw.