Outside of steel and iron, aluminum is one of the most commonly used metals in the world. This is not much of a surprise, considering the fact that it is the most abundant metal in the Earth’s crust. Aluminum is softer and lighter than most other commercially used metals. These traits might make it seem like aluminum would be extremely easy to work with, but it actually poses a unique set of challenges compared to harder materials like steel. If you are looking for the best end mills for aluminum, there are several factors that you have to consider.
You are probably thinking that a soft metal should be easier to cut, and you would be right. Sadly, aluminum is so easy for high speed tools to cut that it does not form the large chips like steel would. Instead, when aluminum is milled it creates chips so fine that they are basically a powder. Because these chips are so small and light, they can cling to your cutting tool instead of being properly evacuated from the cutting area.
In order to ensure proper chip evacuation, the best end mills for aluminum alloys have specially designed flutes to help eject the fine aluminum chips. Your average end mill is going to have a helix angle(the angle between the tangent of the flute’s cutting edge from the central axis of the tool) of about 30 degrees. When you are dealing with aluminum, you want a high helix angle in the 35 to 45 degree range. This steep helix angle will provide a better chip removal rate when you are CNC machining aluminum.
Along with a higher helix angle, you should also be looking at the flute count. You are going to want to look for lower flute counts so your flutes will be wide enough to easily evacuate chips. Most end mills for aluminum are going to have only two to three flutes. Higher flute end mills will not provide efficient machining and powdered aluminum can easily cake around the base of your end mill, potentially damaging your workpiece and you end mill.
If you want the best possible tool life, you will want to choose a solid carbide end mill. While aluminum is soft enough to be cut by steel tools, carbide tools will have more wear resistance and superior edge retention. Many aluminum end mills are also treated with zirconium nitride. This golden colored coating not only provides a hard and erosion resistant outer shell, but it also lowers the friction of the end mill, making it easier to expel chips.
If you want to find the best end mills for aluminum from a quality American manufacturer, you need to check out the tools offered at Online Carbide. They sell three flute solid carbide end mills for aluminum. These end mills range in size from ?” to ¾” with 37 degree helix angles. They coat their aluminum end mills with ZrN to provide extra resilience. All of their end mills and drill bits are precision machined using advanced 5 axis CNC grinders.
To see their entire inventory, you can visit www.onlinecarbide.com. Unlike many tool makers, Online Carbide does not deal with middlemen, meaning you can save big with their manufacturer direct pricing. If you have any questions about their tools or the process of placing an order, you can contact a member of their team by calling 630.238.1424 or sending an email to firstname.lastname@example.org.