Solid Carbide Cutters - General purpose vs High-performance Tools

General purpose solid carbide cutting Tools are a cost-effective solution for general purpose machining. Consisting of 2, 3, 4 flutes, 30-degree helix, coated and uncoated. Available in endmills and ball nose cutter.

These are good value cutters for multipurpose general machining applications. They are not recommended for production parts or high-speed machining applications.

High performance solid carbide cutting Tools will have more advanced grind and technical properties to the cutter, which includes a variable helix and variable index cutting flute. A special coating may also be applied for high performance cutting strategies.

On a standard tool the flute is 30 degrees, whereas on a high-performance cutter it will tend to be 38 to 42 degrees. Different manufacturers may have different flute helixes.  

Variable helix end mills are cutters with different helix angles for each flute. They have high dynamic stability as they are capable of damping vibrations at resonant frequencies of the tool. As a result, these tools experience less chatter and produce a better surface finish.

If you look at a standard endmill you will notice a cross at the bottom. It should be a cross (+). A variable Index looks slightly different. The cross is off centre in comparison, allowing for reduced vibration when plunging or helical cutting.

High-performance Tools are commonly used when higher speeds and feeds are required. Reducing cycle time and improving MMR (Metal Removal Rate). They will also give a better surface finish than standard helix endmills and higher feed rates.

There is a misconception in industry about the type of Tools available and the pricing brackets that they come under. It is always worth making sure that you are using the right Tool for the job.

This will avoid instances such as using multiple General-purpose Tools on a part that could have been performed with just one high performance Tool - resulting in a lower cost per part.  

We’ve also experienced customers buying high performance Tooling when there is really no need for it. For example, if you’re machining a small part, or time is not critical, a standard cutter would do the job. Instead, we see customers using high performance Tooling, which increases the cost per part. In this example the customer is also not using the tool to its optimum performance/ tool life, which adds to the costs.

You’d use General Purpose Tools/ standard end mills if you are…

·       A traditional machine jobbing shop or a small manufacturer and you machine a variety of different materials across a multitude of parts

·       Use Online Programming at the machine to programme linear moves from ‘A’ to ‘B’, rather than using CAM software or the latest cutting strategies

·       Not time pressured

·       Performing very basic cutting moves, or low volume features. E.g profiling and counterbores.

It might be the case that you’ll use the Tool once, put it away and it won’t be used for another two weeks – or you even throw it away after use.

You’d opt for High-performance Tools if you…

·       Are running a production job

·       Need better tool life

·       Need a better surface finish

·       Are using quicker roughing strategies, full depth cutting or high-speed machining

·       Are running Offline programming with CAM software involving high-end tool paths, roughing strategies or more complex 3D models

High performance tools tend to lend themselves better to new cutting strategies such as Trochoidal machining, involving a bigger depth of cut using the full flute of the tool, but taking small step overs with higher feed rates, increasing your MMR and improving surface finish.