When undertaking a new woodturning project, there are many different considerations that can make things overwhelming; one of those is choosing the right screws. Determining the correct size, length and gauge of wood screws can be difficult when building woodturning projects. One only has to enter their local hardware store to see the vast number of screws available, only adding to the confusion. To help make the process easier we have collected together some general guidelines that will help you to choose the right screw for the job.
What You Need to Know
Most screws are made out of steel, stainless steel or aluminium. They can also be chrome or brass-plated and you can even get specialised screws made out of other materials like nylon or plastic.
Steel or stainless steel wood screws have thicker bodies and are typically used for precision woodworking. When you buy wood screws, they are identified both by their length and also by their gauge, which refers to the thickness of the screw shaft. Larger gauge numbers indicate screws with thicker shafts. More information about this is below.
The most important factor in screw selection is length. The length given for a screw is the length that is buried in the wood or other material; it does not include the head of a raised, or domed headed screws. The length of the screw must be long enough to hold everything together but not too long for the ends of the screw to appear through the other side. The general rule of thumb is that the screw should enter at least half the thickness of the bottom material.
The gauge of the screw refers to the diameter – the larger the number, the larger the diameter. Screws that are too thick can split the wood while screws that are too thin won’t be secured in the wood. Hardwoods such as oak or walnut are inclined to splitting, but softwoods such as pine or cedar are less prone to splitting. Interestingly, there is no direct link between the head size of an imperial screw and the gauge of that screw. The gauge (imperial) roughly equals the screw head size in mm. A 5 gauge screw will have a head that is approximately 4mm wide.
Thread, Tip and Head
The thread, tip and head of screws all vary for different applications. The thread will determine the speed that it can be driven in and how it will hold. The head will hold the drive and transfer the force from the driver into the screw, but it will also stop of the material being fixed to hold it.
Drilling a pilot hole in hardwoods is generally recommended before driving the screw. When turning a bowl, drilling a pilot hole will prevent cutting through the bottom.
Utility Screws vs. Steel Screws
There are two forms of woodworking screws: steel/stainless steel wood screws or utility screws.
Utility screws are available in different types of steel, sometimes corrosion-resistant metals designed to stand up to the chemicals in treated lumber; and they are normally sold by length.
Other tips when using screws:
– Lubricate screws with soap or wax for easier installation
– Whenever possible, hold the work in a vise or clamp when inserting a screw. If this is not possible, keep your hands and other parts of the body away from the tip of the driver.
– A screw can be reused over and over again. They can usually be easily removed with little damage to the materials should you want to take something apart.
The professional team at Mayama are also available to assist you with any questions and to guide you to choosing the right screws for your project. Contact the team today on 1800 308 383 or email [email protected]