Screw It: How To Choose The Right Size And Type Of Screws

So Many Types Of Screws 

To anybody that has undertaken any do-it-yourself project, from simple maintenance, repair or full-blown restoration, one item that is the most commonly used yet least understood is the simple screw.

From wood screws to drywall screws, masonry screws, deck screws to metal screws, from galvanised to anodized and from zinc plated to stainless steel, there are so many different types for different applications to choose from and not only the type of screw but the all-important gauge size. Knowing which one of the range to buy can be a minefield to the untrained do-it-yourself novice and even to some skilled tradespeople, but here, we hope to give you a handy guide of what to look for in the confusing world of screws.

Origins Of The Screw

The origins of the screw can be traced back to ancient times, but not in the way we know it nowadays, where it was used in various applications such as pressing grapes and olives. 

Screws have been around for thousands of years, with evidence of their use dating back to ancient Greece and Egypt. However, it wasn’t until the 15th century that screws began to be used for more practical purposes, such as cabinet makers fastening objects together.

What Were The First Screws Made From

The first screws were made from wood and were used primarily in woodworking projects. These early screws had a simple design, consisting of a pointed end that could be twisted into the material being fastened.

As metalworking techniques improved, screws began to be made from metals such as bronze and iron. These early metal screws were typically handmade by blacksmiths or other skilled craftsmen and women. They had a more complex design than wooden screws, featuring threads that spiralled up the shaft of the screw.

It wasn’t until the Industrial Revolution that machines were developed to mass-produce screws, making them more readily available and affordable for everyday use.

Is There A Patent On The Humble Screw

A patent is a legal document granted by the government to an inventor for their invention. It gives them exclusive rights to make, use and sell their invention for a certain period of time. The question of whether there is a patent on the screw can be answered with both yes and no.

The first recorded patent for a screw-cutting machine was issued in England in 1760. However, this did not cover the actual design of the screw itself but rather the method used to produce it. As screws had been around for centuries before this, it is safe to say that no single inventor could claim ownership of the idea.

While there may not be one specific patent on the screw as we know it today, there are undoubtedly many patents related to different types and uses of screws. For example, there are patents on self-tapping screws, wood screws with special coatings or shapes designed to prevent splitting or improve grip, and even medical implants that utilise threaded screws. So while you won’t find a single “screw patent,” if you’re looking to create your own unique type of fastener, you will want to research existing patents first!

What Is The Difference Between Wood, Drywall And Metal Screws

Wood screws, as the name suggests, are designed to be used with wood materials. They have a pointed tip that helps them penetrate the wood easily, even hardwoods, and coarse threads that provide strong holding power. Wood screws come in different lengths and gauges, depending on the thickness of the fastened wood.

Drywall screws, often black in colour, are specifically designed for drywall, plasterboard or gypsum board use. They have fine threads that allow them to grip the soft material without tearing it apart. The drywall screws provide a feature of a bugle head which can sit flush with the surface of the plasterboard and prevent damage to it during installation.

Metal screws are used for fastening heavy loads and metal objects like steel, brass and aluminium together. Unlike wood and drywall screws, they typically have sharper points to pierce through metal studs and heavy surfaces easily. Metal screws also tend to be stronger than other types of screws due to their thicker gauge wire construction. Some common types of metal screws include machine screws, self-tapping screws, and sheet metal screws.

By understanding these critical differences between wood, drywall and metal screws, you can ensure you choose the right type of screw for your project needs. Whether building furniture from scratch or simply hanging some shelves on your wall – selecting an appropriate screw is essential for ensuring a safe and secure result.

Which Finish Do I Need

So, to get things more complicated in the world of screws, they also come in various types of thread finishes. This means what they are coated in, and some coatings are specific to the task at hand, so worth understanding the basics on this too.

There is nickel, zinc plated, galvanised, chromium, stainless steel, black oxide, iridite, anodising, and the list goes on. It can be very confusing, even to me and my experience in the construction and building industry.

Fundamentally, if you are using the screws for outdoor applications or in the garden, then it is recommended that you use galvanised, stainless steel or zinc screws as they have much higher corrosion resistance.

For interior tasks, you can use any coating as the risk of corrosion is far less.

How Do You Get The Right Size Screw

Determining the right size screw for your project is crucial for its success. The first step in getting the right size screw is determining what type of material you will fasten. 

Once you have determined the type of material you will be working with, it’s time to measure the thickness of that material. This measurement will help you select a screw length that ensures a secure hold without protruding through the other side or being too short and not providing enough grip.

Another important consideration when selecting the proper size screw is determining its diameter or gauge, as it is often known in the construction trades. Screws come in various diameters or gauges, and choosing one that fits snugly into your pre-drilled hole or pilot hole helps ensure maximum holding power and stability. Considering these factors can help ensure your project stays securely fastened together for years to come.

Are Screws Better Than Nails

Screws and nails are commonly used in construction and do-it-yourself projects, but which is better? It depends on the application. Nails are great for quick and easy installations, while screws provide a much stronger hold.

When it comes to woodworking, screws are often preferred over nails because they can be easily removed if needed without damaging the wood. Additionally, screws have threads that grip the wood fibres tightly for a stronger hold compared to nails.

In contrast, nails may be more suitable for certain applications, such as framing or attaching thin materials like drywall. They can also be faster to install than screws since they don’t require pre-drilling or threading. However, if maximum strength is needed for these applications, using screws instead of nails would be recommended.

Top Tip: From an old craftsman. Before drilling the screw into timber, rub it with a candle, making retracting it easier for the next time!

A Simple Guide To Screw Sizes

So now you have the knowledge of their history, their materials and why we use them more than nails, you can now gain an understanding of what sizes mean and which one best suits your renovation or repair project.

On boxes or packets of screws here in the UK, there will be two numbers, and we hope to teach you what each one means: For example, 3.5 x 50mm.

These two measurements give you the diameter/gauge and the length. 

• The first measurement is the diameter/gauge and is in millimetres. This will range anywhere between 1mm and 25mm, depending on the length and purpose of the screw.
• The second measurement is the length of the screw and again in millimetres, and these go from 5mm anywhere up to 300mm again, depending on what you need it for.

Top Tip: Sometimes, here in the UK, the second measurement, the length, will also be given in inches, the old imperial system, as well as metric measurements as this is a throwback to the days before decimalisation. Here is a handy conversion chart for those who need it.

In Conclusion

The array of screws and their sizes, coating, diameter, length, durability and materials available are pretty breath-taking, but with the right advice, care and attention, you can find the right box of wood screws, pan head screws, round head screws, self drilling screws and good old fashioned flat head screws for the job in hand.