How to buy and use a Try square for wood and metalworking
The ability to accurately measure, check and mark sizes and positions for any DIY project is a key skill that will help provide great results and ensure the quality of your work.
To help get the best results, good quality measuring and marking tools should be an integral part of every DIY toolbox.
Alongside a good tape measure, Set square or Try Square is probably the most used marking tool in a workshop.
Here’s our guide on how to use and look after your set squares to get the best results and take your projects to the next level.
What is a Try Square?
A try square is made of two parts which are joined at 90° to form an ‘L’ shape. The first part is called a blade, also called a tongue or beam, this is a flat, thin face with 2 parallel edges.
The second part is the stock, which is usually thicker than the blade and provides a shoulder or edge, for use when marking.
Common materials for Try squares are a hard steel blade and separate wooden, plastic, or metal stock, which is fixed accurately to the blade using rivets.
Try squares are often made in one piece for accuracy and include a stock that is cut at 45 degrees, and used for checking and marking out miter joints.
What is a Try square used for?
Try squares are used for checking corners and joints of materials like wood or metal, to make sure they are square and true.
Both internal and external 90-degree corners can be checked using a try square.
By holding the try square against the edges or corner you want to check, the accuracy of the joint to 90 degrees can be clearly seen.
Holding the try square and workpiece in front of a light source, such as a workshop lamp or light bulb, allows light to shine through any gaps between the face of the square and the work surface.
Adjustments can then be made to reduce these gaps, usually by filing or sanding the workpiece.
The edges are rechecked and the process is repeated until no gaps can be seen between the try square and the work surface.
Feeler gauges can also be used to check the fit of a corner or join against the surface of a try square.
One of the main reasons for using an accurate try square is that a corner or face is much easier to join or fit when it is square and close-fitting joints help provide structural stability.
Try squares are also used when marking out workpieces, to give accurate positions for hole centers, edges, and cutlines.
The stock of the try square is usually held against the edge of a workpiece and the tongue is used as a reference to mark a line on the work surface, perpendicular to the reference edge.
Use a sharp pencil on wood or a scribe on metal surfaces to mark the edge of the square and the position required.
How to choose a Try square
As with most tools, it’s worth spending a little bit more for as good a quality piece of kit as you can afford.
And try squares are no exception, try to buy (no pun intended) the largest Square you can afford, as it will allow you to work with larger projects than just a small unit.
Having said that, owning a small square can also be useful for small projects and fine detail work.
Typically try squares are available with blades up to 300mm or 12” and longer in some circumstances. I own several try squares of different sizes and use them for different sizes of workpiece.
When choosing a try square I recommend that you choose one that is made from one piece or material preferably metal, they are known as Engineers Squares and they are generally more accurate and will last longer than wooden versions.
The downside is that they are more expensive and probably not for use on a job site where they can be damaged or lost.
A try square made from a blade and stock that are separate pieces riveted or fixed together, can work loose over time and will not be as accurate but will be cheaper to buy.
They can also be damaged if dropped as the shock can spring the joints, pushing the tongue and stock out of square.
Try squares should be checked regularly to ensure they are still true.
Other types of Square
Try squares are just one version of this checking tool that can be used for marking and measuring right angles, and 45 degree miters, here’s a list of others that can be great additions to your tool kit,
| Type of Square | Purpose | Pros | Cons |
|---|---|---|---|
| Try Square | Wood-working, furniture making and general 90 Degree joints | Good all round tool for checking 90 degree joints and cuts | Limited to 90 degrees and various sizes are required |
| Engineers Square | Fine woodwork, metal work, high accuracy | Robust and accurate | Expensive and not for jobsite use |
| Combination square | Covers a wide range of joints at different angles | Versatile for multiple joist and cuts | Can be expensive parts can be lost easily |
| Roofing square | For jobsite work and structural roofing members | Large multi use square for various angles and cuts, robust enough for jobsites | Not as accurate as an Engineers square |
| Speed square | Smaller jobsite and general use for miters and 90 degrees | Smaller version of the roofing square | Can be too small for larger jobs |
| Framing square | For carpentry and extended marking into framing, rafters and stairs. can be used as a straight-edge and marking off positions on widestock wood | Large size and ruled edges | Too large for fine or small work. |
| Sliding Bevel | For finding unknown angles and odd joints | Easy to use and fits in any tool box | Often small and can be delicate if not handle correctly |
| Drywall square | Large Tee square typically 50” on the tongue for marking large sheet materials | Great for large flat sheet materials | Large and take up space only for full size sheets |
| Hand Saw | The handle provides a square guide for quick marking and cuts | Cheap, quick and ready to hand | Not very accurate. |
It’s also good to know that most modern hand saws have their blade set at 90 degrees to the handle which can be used as a quick guide for cutting square joints.
How to look after a try square
With great tools comes great responsibility or something like that. Investing in good quality tools should be a serious business, as should looking after them and treating them well as this means they will last you a lifetime.
I recommend you keep your job site tools separate from your workshop tools and where possible provide dedicated storage areas for both.
I have a separate tool bag for my job site marking tools and in my workshop, I have a shadow board where I store my high accuracy tools each one has specific spac
If you throw your tools into your toolbox without care, they will be damaged, dented, bent, and quickly be of no use.
When you have finished your marking task, always wipe down our try square to remove any dirt and check for damage, then place it back in the allocated storage space.
I force myself to replace them when I have finished, after a while it becomes a habit, and I always know where to find them when I need them.
Once a quarter or at least once a year inspect your try square checking for damage or wear and tear, make sure the tongue and stock are solid and the joint has not flexed, use a good quality workshop or engineers square to check the others.
Clean them with isopropyl to remove any dirt and cover them with a light grade machine oil and wipe any excess with a dry cloth.
Either repair or replace any worn or damaged tools to ensure you keep marking and cutting at 90 degrees.
This article was written by: Richard Quinton – The DIY Help Desk Owner, Engineer & technical specialist.
Richard is one of the key partners in The DIY Help Desk team. He is a qualified Engineer, writer, and publisher, educated to Master’s level. He is a keen advocate of DIY and home improvements.
Richard enjoys helping others to learn new skills and reach their goals and believes that passing his knowledge and experience on through his writing is an effective way to positively impact the lifestyles and well-being of others on a larger scale.
