Screwdrivers Screw Extractors

When Were Screws First Used? Brief history of Screwdrivers.

No one really knows the first time that screws were used to fasten parts together. However, there are instances of screw type tools being used going back to the first century. These screws were made out of wood.

The first metal screws started coming into use around the 15th Century. It wasn’t until the 18th Century, however, that screws would become easy to produce and, thus, popular tools for building.

In 1770, Jesse Ramsden, an Englishman, invented a lathe that could cut screws. Inventors continued to improve upon this design until 1797, when a lathe that made it possible to make screws that were of a consistent size and on a massive scale was invented by Henry Maudslay.

P.L. Roberton came up with a screw that could be mass produced and that had a square driver design. It wouldn’t be until the 1930s, however, before Henry Phillips came up with the Phillips screws that are so familiar today.

The drivers used on screws are important considerations as to whether they’re actually practical. The Philips head screw, and others with square designs, provide greater stability for the screw driver. Where a standard, slotted screw is prone to slipping the driver when it’s being tightened or loosened, screws with square patterned heads prevent the driver from slipping out of the slots, making them much more stable to work with. They’re also easier to use with automatic drivers, which can put out a considerable amount of torque and which may slip on a standard screw head.

Screw drivers have been in use since the 1800s and are fitted to the various types of screws on the market. Today, there are many different types of screwdrivers available, owing to the many innovative head designs that have been released onto the market over the years.

 

When to Use a Screw versus a Nail?

For most structural applications, nails are preferred over screws. They’re less brittle. As a real life example of this, if you hit a nail off centre with a hammer, it will usually bend. A screw will break. Screws, however, have significant advantages over nails in certain applications.

The most obvious difference between a screw and nail comes down to control. Inserting screws is much easier than nails, as the screw drives itself into the hole due to the corkscrew pattern cut onto its surface. If the screw needs to be removed, doing so is much easier than removing a nail.

Screws are, overall, better fasteners than nails. They’re also better for cosmetic purposes. Nailing a board onto a deck, for instance, is likely to leave dents in the wood, which screwing will not do. Screws can also be very precisely torqued, allowing them to provide a firm fastening between two objects without having to drive a nail far into a piece of wood or another material.

Of course, on materials that cannot be nailed—metal, etc.—screws are the best choices. They can be inserted into pretapped holes, providing a way to join parts together firmly and reliably. If the screws used in these projects—or any other projects—rust or corrode, they can be easily removed and replaced, which isn’t necessarily true of nails.

 

What Are Screwdrivers?

Screwdrivers are hand-held or mechanical devices that rotate a screw into materials or out of materials. They come in many different sizes, designs and materials.

Heavy-duty screw drivers are usually outfitted with one particular type of driver. A Philips versus a standard screwdriver, for instance. New screw heads are coming out all the time and there are already many variations on the market, so there are many different types of drivers available.

Screw drivers sometimes have changeable bits that allow them to be used for many different types of screws. The most common have a Philips and standard head, usually at least two of each in different sizes. More complex drivers may have a hex head, a torq head or another type of head included with them. There are also entire kits available that have many different types of screwdriver heads in varying sizes.

A handheld screwdriver usually consists of three separate parts. There is a handle designed to allow sufficient grip to turn the screw into or out of materials. There is a shaft, which may be very long or very short, in some cases. The end will have either a socket for changeable screwdriver heads or be cut into the shape of a particular type of screw.

 

What Are Ratchet Screwdrivers?

A ratchet screw driver saves labour by driving in the screw—or extracting it—mechanically. The handle on these devices are made to be pushed downward, which rotates the shaft of the screwdriver. The screwdriver will usually have a switch that allows it to be used to insert or extract screws.

Ratchets only turn in one direction, which allows a screw to be driven by repeatedly pushing the handle down and turning the screw, and then retracting it without turning the screw in the opposite direction.

 

What Are Torque Drivers?

A torque driver is a type of adjustable screwdriver. The adjustment controls the amount of rotational force—torque—applied to the screw. These are important in applications where too much or too little torque may affect how equipment performs, such as when tightening screws on mechanical devices. It is also effective in preserving fragile materials, such as PCB boards, by limiting the amount of torque exerted on the screw.

 

What Are Screw and Nut Starters?

A screw starter holds a screw in place before it is tightened. These are particularly useful in applications where the screw has to be inserted into an area where it is hard to reach. Many of these devices are equipped with a magnet on the opposite end of the device, allowing the screw to be retrieved if it is dropped somewhere inaccessible.

 

Screwdriver Bits and Bit Sets?

Screwdriver bit and bit sets provide a simple solution to the many different types of screws on the market. They come with drivers that allow the user to change out the heads as needed, providing a fast and simple way to deal with jobs that involve more than one type of screw.

 

What Are Screwdriver Sets?

Screwdriver sets are similar to screwdrivers bit sets but, instead of containing a variety of different threads, they commonly contain several different handheld screwdrivers. These are must haves for maintenance personnel, mechanics and other workers who need the strength of a regular screwdriver but who need it in many different forms and with many different heads.

 

What Are Screw Extractors?

Screw extractors are devices that are used to extract screws that have become permanently embedded in the material they were driven into and screws that have broken heads or that have the slot for the driver stripped out. These devices require the user to employ a drill to drill out the screw itself to the size required for the extractor. The extractor is then driven into the screw and the screw extracted by turning it out of the hole.

There are many different designs of these devices, some proprietary. They are important tools for anyone who works with fasteners and they can prevent a great deal of damage by offering an easy and controllable way to get a broken screw out of materials.

 

What Types of Screw Drives Exist?

There is a huge number of screw drives on the market. To get the best results, they have to be used with the proper type of driver. Some drivers will fit into the wrong screw somewhat, but this always diminishes control over the screw and may strip the head.

 

Breakaway head

A breakaway head screw is designed to provide security. After the screw is tightened into the place, the head breaks off of the screw. This prevents anyone from being able to remove the screw. They have to be chosen so that the breakaway force is not too great or too little compared to the force needed to hold the materials together.

 

Bristol

This is a spline type screw that can have four or six splines cut into the head. The design places the force of the torque exerted on the screw at right angles to the face. They are hard to strip, which makes them good for high torque applications.

 

Claw

A claw head has two projections on the screw that are aligned opposite to one another.

 

Clutch

Clutch screw drives come in two styles. The first type, Type A, has a bowtie design. The second type, Type G, is shaped like an hourglass.

 

Combination drives

Combination drives allow a user to utilize more than one type of screwdriver to insert the screw into a material. They are often combinations of Philips and standard heads, torq and slotted or other combinations that make it easier to work with the screw.

 

Common types

Common types of screws include slotted screws, cross, Philips and Frearson designs. These are seen in myriad applications. Some of them can be used with the same driver as another, such as cross, Phillips screws.

 

Cross

A cross screw is similar to a Philips screw, but it has a less complex head shape and doesn’t have the same protection against over tightening as does a Philips screw head. These can be tightened with cross or slotted screwdrivers.

 

Cruciform types

These have a cross shaped head with a recessed design.

 

Double hex

These screws have two hexes that make up their driver shape. They generally have a larger driving shape and have good qualities for high torque applications.

 

Double-square

A double square head has two offset squares for its drivers, making 8 points in total.

 

External types

An external type screw is one that uses a female tool rather than a male tool, the fastener itself has a male drive.

 

Frearson

These are poplar in maritime applications. One Fearson driver can fit any Frearson screw and torque handling is very high.

 

French recess

These drives have a recessed portion and require a special bit to tighten or extract.

 

Hex

A hex screw is a six-sided design.

 

Hex socket

A hex socket has a six-sided, recessed design. These are also called Allen screws.

 

Hexalobular socket

Hexalobular sockets are more commonly referred to as torx screws. These have a star-shaped driver and handle torque very well.

 

JIS B 1012

These screws look much like a Philips screw drive, but they have no cam out ability and need a special screwdriver.

 

Line

These are tamper resistant screws that come from Japan. They have a six-sided drive design.

 

Mortorq

A variation on Philips head screws that handles high torque better.

 

One-way

A one-way screw is a tamper resistant screw that cannot be extracted with a driver once inserted.

 

Pentagon

A five-sided drive requiring a special driver or socket.

 

Pentalobe

A five-sided tamper-resistant screw used by the Apple corporation.

 

Phillips

A very common type of drive designed to cam out at high torques. It has a “+” shape to it, with a circular middle portion.

 

Phillips/square

A combination drive that can be used with Philips or square drivers.

 

Polydrive

A six-sided drive able to handle very high torque.

 

Pozidriv

These screws are designed to not cam out as easily as Philips screw drives, but look very similar. They have an extra set of indentations on the screw head.

 

Proprietary head

A proprietary head is one used exclusively by one company or manufacturer.

 

Protruding obstacle or pin type

A type of tamper-resistant screw that requires a special tool to insert or extract.

 

Robertson

A square drive, predecessor to the Philips screw.

 

Slot

A standard slotted screw with a single indentation.

 

Slotted types

Slotted types are driven by flat bladed screwdrivers.

 

Slotted/Torx

A combination drive that can be used with a slotted or torx driver.

 

Spanner

Spanners have two holes that drive the screw and are tamper resistant.

 

Spline

A high-torque design with a 12-spline design.

 

Square

A simple square drive.

 

Supadriv

This type of screw is nearly identical to a Pozidriv screw. The secondary blades are larger and the drive blades are equally sized, differentiating these slightly from a Pozidriv.

 

TA

A triangular drive that is tamper resistant.

 

Tamper-resistant types

Tamper resistant screws are designed to prevent extraction or tightening by unauthorized individuals. There are many types.

 

Thumbscrew

A thumbscrew is designed so that it can be tightened or loosened with a driver or the hand. They’re popular on computer cases.

 

Torq-set

These look like an offset Philips screw drive and are used in the aerospace industry.

 

TP3

A driver with a triangular cut-out with convex edges.

 

Tri-point

These have three slots extending to the edges of the head, arranged in a triangular pattern.

 

Tri-wing

A triangular shape with extending peaks on the triangle.

 

Triple square

Three squares axially rotated.

 

TTAP

A new variant of the hexalobular screw.

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