Did you know your CNC router can handle more than just wood? Learn the relevant details for cutting aluminum with a CNC router, including 7 useful tips!
CNC ALUMINUM CUTTING
Rounding, Cutting, Lettering
When most people think of machining metals such as aluminum, they think of a high-end milling machine. Such a machine is capable of extremely complex work, with spindles spinning the cutting tool at speeds comparable to most high-speed drills.
A CNC router, however, has a spindle operating at a much higher rate of speed than a typical mill. They are primarily used for cutting wood materials in operations such as rounding edges, slot cutting, or lettering.
Although it might not always be expressly mentioned, CNC routers are capable of cutting aluminum, in general. In the following, we’ll take a closer look at how this is possible and review a few tips that’ll make it easier.
Cutting with a Router
First, let’s take the opportunity to explain that, here, “cutting” refers to both the separation of an aluminum sheet into two or more pieces as well as slotting or making pockets into an aluminum plate. Basically, we are referring to the removal of material from either aluminum sheets or plates. This is done through the use of an endmill cutting bit.
Machining aluminum with a CNC router should be possible with most any CNC router. By matching the material with the appropriate endmill bit and feed rate, you can make cutting aluminum a breeze.
Always make sure to read your particular machines instruction manual fully and have a working knowledge of your equipment. Depending on the manufacturer, cutting aluminum might void your equipment warranty, so take special note of manufactures specifications.
Next, before we get into the cutting, it’s important to know that, any time you have a highspeed cutting bit removing materials from any material, always wear safety glasses and keep hands clear of moving parts.
Learning to be successful may mean broken bits. These can become dangerous projectiles, so always make sure you’re following all of the safety measures recommended by your machine’s manufacturer.
Tips to Success
Knowing these steps to cut aluminum with your CNC router can be the difference between a good day in the shop or dodging a broken cutter bit that’s been hurled across the room at you.
- Take your time. Material removal rates will be slower than those on a mill, but since most CNC routers handle material larger than a standard mill, the speed to size ratio is a good trade-off.
- Use the proper router bit. Use a 2 or 3 flute carbide endmill. They allow for a higher spindle speed on your router. Avoid cobalt and HSS cutters for working with aluminum.
- Use smaller diameter cutters. Forget about 1/2″ endmills and go to 1/4″ or smaller. This allows higher feed rates and makes for smoother cuts.
- Clear your chips. Keeping the chips clear of the cutter will avoid breaking endmills. If available, use an air blast aimed at the point of the endmill cut. This will keep your cut clear of chips that can build up and break your cutter.
- Lubricate. The use of lubricating oil is highly recommended. It will not only make cutting easier and your success rate higher but aid in keeping your cutting edges sharp. For best results, set up a mist oiler that works with your air blast as you remove the chips.
- Avoid overly slow feed rates. By slowing the feed rate too much, you run the risk of making your tool rub instead of cut. Because the spindle is going so fast, this is can be a larger risk for CNC router users than for mill users.
- Learn from your errors. As with anything, there will be a learning curve. Success comes from persistence. Mistakes happen — the key is to always stay safe and learn from them.