Aluminium bar stock is used in all kinds of projects, from window frames to aircraft landing gears. Its impressive formability means it can be turned into a variety of shapes – round, flat, square, even hexagon! It also comes in a huge range of sizes and thicknesses, so you can find the right fit for whatever you’re building.
This variety has one drawback: knowing which bar stock to use for your project isn’t always easy. Luckily, that’s where the metal specialists at MG Metals come in! Keep reading for our step-by-step guide to choosing the perfect aluminium bar stock, taking a look at everything from shape and size to grade and beyond.
1. Shape
The shape of your bar stock has a huge impact on what it can be used for, so think carefully about how it will look and how it will function when picking one out. Here’s a breakdown of the pros, cons, and some examples of the most popular shapes:
Round Bars
Aluminium bars are ideal for applications needing low-friction rotation due to their smooth, continuous surface. On the flipside, they’re not as strong in bending as flat or square bars, making them less suitable for bearing heavy loads.
Examples: Shafts for motors, axles in wheels, pins and bushings in moving parts, decorative railings with smooth curves, electrical busbars for conducting current.
Flat Bars
Flat bars offer a strong and rigid surface with two flat faces, making them perfect for easy attachment using screws, rivets, or welding. They can also be easily machined for customisation. However, their flat profile makes them less suitable for applications that require a finished look on all sides.
Examples: Brackets for shelves or fixtures, supports for structures, spacers to keep components apart, decorative trim with a flat profile, bus bars in electrical panels, heat sinks that dissipate heat from electronic components.
Square Bars
Square bars offer strong overall strength and a stable grip when inserted into square holes or channels, making them ideal for load-bearing applications. However, their corners make them unsuitable for applications requiring rotation, and they can create stress concentrations, often requiring deburring for certain uses.
Examples: Structural components in furniture or frames, legs for tables or chairs, tool handles that need a secure grip, machine parts requiring strong connections.
Hexagonal Bar
Hexagon bars combine the main advantages of round and square bars. Their flat sides provide a good grip and more wrench flats for easier turning with tools, and they can be used on a flat face or a corner for greater versatility. On the other hand, their complex design also makes them harder to machine compared to round, flat, or square bars.
Examples: Shafts for levers or cranks that require occasional adjustment, fasteners like bolts or nuts, bushings in machinery, decorative elements in furniture or architectural features with a unique touch, bike components like handlebars or seat posts.
2. Size
Once you’ve decided on the right shape for your project, you need to think about size – namely, thickness / diameter and length. Read on to learn more.
Thickness
The right thickness for your bars depends on several factors. Here are some questions to help you decide:
- What will you be using the aluminium bar stock for? Different applications require different strengths and weight limitations. For instance, thin bars might be better for decorative purposes, while thicker bars are needed for structural support.
- How much weight will the aluminium bar need to support? Aluminium comes in a variety of alloys, each with its own strength properties. It’s a good idea to consult a reference table to find the appropriate alloy and thickness combination to bear the desired load.
- Is there a weight restriction for your project? Aluminium is known for being lightweight, but thicker bars will naturally weigh more.
- How will you be working with the aluminium bar? Thinner bars are easier to cut and bend, while thicker bars might require special equipment or techniques.
Standard sizes are available in both imperial and metric units.
Length
Picking the perfect length for your aluminium bar stock depends on what you’re building. Here are some questions to help you decide:
- What dimensions will you need for the finished product? Account for any bends or shaping that might alter the overall length.
- How can you minimise material waste? Check with suppliers about standard lengths and aim to get a bar close to your final dimensions. Many suppliers can also cut bars to your specific requirements, eliminating waste even further.
- How will you transport and handle your aluminium bars? Extremely long bars might be difficult to move or may require special handling equipment.
- Do you have any fabrication limitations? Some processes, like bending or machining, might have limitations on the maximum workable length. Check your equipment’s specifications for guidance.
3. Alloy Grade
Different aluminium alloys offer varying degrees of strength, weight, and corrosion resistance. The most common grades for bar stock include 6061 (general purpose), 6082 (stronger), and 5052 (highly corrosion resistant). Here’s a breakdown of all three:
Grade 6061
Grade 6061 is a versatile and popular grade due to its good balance of properties. It’s heat treatable, meaning its strength can be increased through a heating process.
Applications include: Building frames, bridges, towers, aircraft landing gears, truck bodies, bicycle frames, and electronics housings.
Grade 6082
Grade 6082 is a newer alloy with even higher strength than 6061. It’s also heat treatable.
Applications include: Gears, shafts, heavy machinery, cranes, and other high-stress components or structures.
Grade 5052
Grade 5052 is a non-heat treatable alloy with excellent corrosion resistance and weldability. It’s not as strong as the others, but it’s easier to form and bend.
Applications include: Boats, signs, panels, enclosures, ductwork, tanks, pipes, and other applications requiring corrosion resistance.
4. Finishing
Finally, decide on what finish you want your bars to have. There are a few options available to you:
- Mill finish is the most basic finish, where the aluminium bar stock remains in its raw state after extrusion or rolling. It will have a matte, slightly rough texture with visible tool marks from the manufacturing process. Mill finish is cost-effective and suitable for applications where appearance isn’t critical, or when the bar will be further machined or treated.
- Anodising is an electrochemical process that creates a hard, protective oxide layer on the aluminium surface. It enhances corrosion resistance, improves wear properties, and can provide a decorative finish with a wide range of colours. It’s a popular choice for applications requiring durability and a touch of aesthetics, such as building facades, window frames, or electronic components.
- Powder coating is a dry finishing technique where finely ground powder particles are electrostatically applied to the aluminium bar. The powder is then cured under heat to form a durable, colourful coating. Powder coating offers excellent weather resistance, scratch protection, and comes in a vast array of colours and textures. It’s ideal for applications requiring a high-quality, long-lasting finish on outdoor furniture, machinery parts, or architectural elements.
Elevate Your Project With Premium Aluminium Bar Stock From MG Metals
Need aluminium bar stock for your next project? MG Metals have got you covered. We’re specialists in supplying high-quality aluminium bars in all sorts of shapes and sizes, and we’re here to provide you with the exact bars you’re looking for.
Here’s why you should choose us:
- We have a wide selection of shapes to choose from, including round, square, flat (metric or imperial), and hexagonal. Not sure which one you need? Our experts are happy to chat and recommend the perfect bar for your project.
- We use only the highest-quality raw materials and put our bars through rigorous quality checks at every step. Whatever type or shape you choose, you can be confident you’re getting the strong, reliable components your project needs.
- Save time and money by letting us cut your bars to your exact measurements. No more wasted material or dealing with it all yourself!
- Looking for a specific finish? We offer a range of options like anodising and powder coating, so your bars can look great and be protected for whatever you’re building.
- We offer next-day delivery to get your project started ASAP!
Ready to get building? Get a quote for your aluminium bars online or give us a call on 01794 52107 today!