Aluminum is among the most versatile and widely used metals worldwide in DIY workshops and metalworking facilities. Despite being easily machinable, aluminum does pose some challenges. Because aluminum is typically easy to work with, some beginners have trouble holding their cut lines. Aluminum is soft, heats quickly, and can warp or bend if not cut properly. At best, that leaves the machinist with more work. In the worst case, it can ruin an otherwise good project. That’s why having the right blade, tools, and procedures is essential to make the perfect cut every time.
The Best Tools To Cut Aluminum Sheets and Pieces
Metal shears, or tin snips, are the most common tool for cutting aluminum. Many aluminum projects are small, quick jobs that need some fast trimming. Shears are perfect in that situation. They don’t heat the metal, they can be maneuvered into tight spots for hard-to-reach cuts, and there’s no power requirement, so you can take them anywhere to cut almost anything.
Circular saws are easy to use and widely available. They work well for straight cuts on sheet metal, but they work best with special sheet metal cutting blades. Circular saws aren’t the best choice for thicker sections but are ideal for quick cuts and smaller areas. Circular saws and miter saws are excellent choices for precise cuts on aluminum, especially in preparation for more detailed work.
With a built-in edge guide, table saws can cut a straight edge on sheet metal, including aluminum. Follow the same advice for a circular saw and use a dedicated non-ferrous metal cutting saw blade.
Table and circular saws are best for straight, smooth cuts. Jig, reciprocal, and handheld circular saws can cut curves and shapes in ways that table saws cannot. Bandsaws are also an option, but they don’t offer the same security and power as other options, relying more on the operator’s skill to keep the saw steady and produce a clean cut.
Metal brakes are special metal-cutting machines that use a slightly different approach. Unlike power tools, metal brakes use a bending action to flex and score the metal, causing it to break cleanly along a straight line. Metal brakes are large and can be cumbersome, but they’re one of the best options for cutting long, straight sections of aluminum sheet metal.
A hacksaw is a handy tool for cutting a smaller piece of aluminum. You can use it to cut pipe and bar, but it’s also effective when you need a shorter length of sheet aluminum. Fortunately, there are other blades available if those do not work out or if they wear down quickly over time.
The abovementioned methods work best when cutting aluminum sheet metal or bar stock into more manageable pieces. High-speed CNC machine tools provide some of the best options for more detailed work. CNC lathes and mills turn thick aluminum pieces into finished parts and can be used to create entire production runs of identical parts.
Plasma cutting is a melting process in which a jet of ionized gas at temperatures above 20,000°C is used to melt and force material from the cut. An electric arc is struck between an electrode and the workpiece. The electrode is recessed in a gas nozzle that constricts the arc, causing the narrow, high-temperature, high-velocity plasma jet to form. Plasma arc cutting works on electrically conductive alloys, including plain carbon and stainless steels, aluminum, nickel alloys, and titanium.
Another way to cut an aluminum pipe is with a router. A router table is a safe option, but if you don’t have one, a hand-held router will do the job, too.
Aluminum Cutting Process: Tips and Tricks
When cutting aluminum, remember these tips for making your job a lot easier.
Woodworking tools will work
Since aluminum is one of the softer metals, you can repurpose some of your high-quality wood-cutting tools to cut aluminum as well.
Metal-cutting lubricants help to reduce chatter and inconsistencies during the cut and can also help to remove swarf and chips. The most common lubricant for aluminum is WD-40, but others, such as metal cutting wax and water, work equally well in preventing blades from clogging.
Smaller diameter blades are better
Typically, smaller diameter blades produce cleaner, more accurate cuts because their smaller diameter results in less runout, and less runout means a smoother cut.
Clamp your workpiece
Clamping your workpiece gives it stability, and a stable workpiece allows for a cleaner cut. Another benefit of clamping is it improves safety with less chance of something flying off the saw and harming the operator.
Always wear adequate protective equipment when cutting aluminum or any other material, including safety glasses or safety goggles, and hearing protection. Full-face shields might also be advisable.
Use The Correct Hand Tools
Tin snips and shears, angle grinders, chisels, and carbide blades are all craftsman’s tools for tackling professional or DIY projects. Either way, have the correct hand tools to complement your saws or machine tools. Cutting thick aluminum pipes might require a carbide-tipped metal cutting circular saw blade. Most of these tools are available at retailers such as Amazon.
4 Simple Steps to Cut Aluminum With a Circular Saw
Ready for the simple process? Follow these steps to cut aluminum sheet metal or bar stock.
Set It Up Correctly
Circular saws require clearance beneath the workpiece. If you’re clamping your aluminum sheet to a sawhorse, be sure you’ve got enough support to cut close to the stand without cutting into it. A good setup also requires considering how large the blade is, where it will travel, and if it’s thick enough to offer a clean cut.
Lay Out and Measure Your Cut
If you’re using a CNC machine, you must program the machine with the exact cuts in the operation. If you’re cutting off bar stock, a simple layout line or tape measure will suffice. Aluminum sheets should be laid out so you have something to follow as you cut.
Lubricate The Blade
Use WD-40, water, or cutting wax to lubricate your blade to prevent clogging. A lubricant reduces friction, makes a cleaner cut, and keeps the blade and workpiece from overheating. Keep your blade perpendicular to the workpiece. Angled cuts are thicker since there is more material, leading to distorted or warped cuts and jagged and uneven edges.
Clamp The Workpiece
High-quality, cast-iron C-clamps are a great way to secure your aluminum workpiece. Use more than one clamp along the path of the blade’s travel so that the workpiece doesn’t move from the blade during cutting.
Looking for even more ways to cut aluminum? This video includes a few that aren’t on this list, so feel free to check it out.