Taylor Tool Life Calculator | Machining Wear Planner

Taylor’s equation allow people to mathematically calculate and predict the life of a tool during the machining process. Taylor’s equation is useful in that it shows how the cutting speed of the tool will impact the wear on that tool. Because cutting speed is the most significant factor in the wear of a tool, increasing the cutting speed will result in the tool wearing out at a more faster rate.

In addition, the equation predict that the wear on the tool will increase exponentially as the cutting speed of the tool increases. The formula for Taylor’s equation is VT^n = C. In this equation, the variable V is the cutting speed of the tool, T is the life of the tool in minutes, n is the exponent related to the material of the tool, and the variable C is a constant related to the workpiece material, the tool material, and the machine itself. Through the re-arranging of this equation, you can calculate the life of the cutting tool in instances where the cutting speed is known, or the cutting speed necessary to allow the tool to reach a desired life can be calculated.

How Cutting Speed Affects Tool Life

Because the tool life is dependent upon such a drastic alteration of cutting speed, it is essential to make careful decision in the selection of the cutting speed. The value of n in the equation change according to the material that is being cut. For instance, low-carbon steels has an n value of 0.24, indicating that the life of the tool will drop quickly should the cutting speed be increased for those steels.

Aluminum, a much softer metal, has an n value of approximately 0.3, indicating that cutting speeds for aluminum can be higher than other metals. Metals like titanium is much tougher and have an n value of 0.14, which will cause a large drop in the life of the tool should cutting speeds be increased. Additionally, the constant value of C changes with the tool material.

For instance, carbide tools have higher C values than tools made of high-speed steel, indicating that carbide tools allow for higher cutting speed. In addition to cutting speed and tool material, there are many other factor that impact the life of a tool. For instance, rough turning will cause wear to the tool in a steady fashion, but slot milling tools may lead to a tool chipping because the tool is forced to recut chip.

Drilling and boring operation will also impact tool life due to the need to make pecking motion with drilling tools, or to fight against the deflection of cutting tools in boring operations. Other factor that can impact tool life are depth of cut, feed per tooth, and coolant use. For instance, deeper depths of cut may increase the force on the cutting tool.

Additionally, increasing the feed per tooth will increase the amount of load placed onto the tool. Finally, using coolant will extend the life of the tool; using through-tool coolant may extend tool life by 8% compared to flood coolant. In order to successfully complete a batch of workpiece, these various variable must be balanced with one another.

In instances where 6061 aluminum is being machined, higher values for the cutting speed (due to the high C value for aluminum) and the feed rate will result in the tool wearing out at a faster rate but allowing for the machining of more part before the tool wears out. However, should 4140 alloy be machined, the C value will be lower and the n value will be lower, which require a lower cutting speed to prevent the tool from glazing. Additionally, the machine setup must allow for the tool to remain rigid to the workpiece, since vibration may cause the tool to wear at a faster rate than Taylor’s equation predicts.

Many people make mistake when using Taylor’s equation. For instance, one of the most common is attempting to increase the cutting speed, which will exponentially decrease the life of the tool and lead to increased cost for that tool. Another of the most common mistake is using the wrong material for the tool; for instance, using uncoated carbide tool for jobs that ceramic tools can perform.

Additionally, people may not consider their batch size before implementing cutting speed and other parameter into the equation. For instance, if they are producing many part, they may require a lower cutting speed than those that are performing prototype run. In order to verify the success of the tooling and the cutting speed established for a project, many different metric can be used.

For instance, dividing the life of the tool by the cycle time to produce that part, then multiplying it by the number of edge on the tool, can calculate parts per edge. Similarly, the life ratio can be used to ensure that the cutting speed is not too high or too low. Finally, if the target cutting speed is known in relation to the diameter of the cutting tool, that speed can be converted to spindle setting for the machine.

While Taylor’s equation is a helpful tool for calculating the life of a cutting tool, it isnt perfect; it does not account for sudden fracture in the tool or the formation of a built-up edge. However, it is an effective tool for calculating the life of a tool in most machining situation. Therefore, it is best to use it to set the cutting speed for the tool first, then the feed rate second.