What constitutes a more efficient cutting tool? That of course depends on the type of tool you are currently using and on the application, but there are three factors to look at:

1. Geometry. Often, the primary factor limiting material removal rate is the horsepower of the machine tool. However, some of the newer high feedrate milling cutter inserts feature a more aggressive geometry allowing for freer cutting. This typically takes the form of a lead angle of around 15 degrees. These newer designs permit faster feeds and greater material removal rates without an increase in horsepower.
Tool geometry can also impact chatter. Chatter is often a systemic problem, with insufficient machine and spindle rigidity a frequent contributor; however, there is no doubt that tool geometry is a major factor. Because of their freer cutting action, these newer tool designs decrease the likelihood of chatter. Though difficult to quantify, this tends to increase both part quality, specifically in the area of surface finish, and tool life as well.

2. Coating. This is an involved subject, one that can easily merit an article of its own. However, we will cut right to the chase and focus on a couple of new developments that could have great significance for moldmakers. First, look for roughing grades featuring newer forms of CVD-Al2O3 coating. When combined with newer forms of post-deposition surface treatment, tools with this coating exhibit superior wear resistance and toughness, as well as increased resistance to thermal cracking. This allows the tools to be run at higher speeds, boosting productivity and netting savings in machine, operator and overhead costs. Also, the greater resistance to thermal cracking increases tool life. This decreases tooling costs and, more importantly, it also decreases machine downtime as the machine doesn’t have to be stopped as often to change out chipped tooling. This can have significant effects on a shop’s bottom line.

3. Support. Application support can be a major source of productivity enhancement for moldmakers, one that is often overlooked. Though advertising and promotional material can be helpful, and tooling company salesmen can typically provide useful information, when considering a tooling purchase these two sources of information are not enough. Moldmakers should contact the cutting tool company’s applications staff. These are the people who should be able to provide you with real-world information relevant to your specific applications. After discussing your needs with an applications professional, you will probably wish to test the product in conjunction with that applications professional. Along with imparting information about tooling, a knowledgeable applications professional can sometimes provide you with valuable insight into your overall production process.