I’d like to start out by explaining what a specification is. If you look in the dictionary, basically a specification is a means to define, or a description. Specs are used by machine tool buyers to compare different products and predict expected performance.

Standards
Consumers needed a way to evaluate different machines, so pressure from consumers caused “standard” specifications to be adopted by builders in major market areas to compare characteristics. However, this tended to be market based, so there was a different standard in the U.S., in Asia, and Europe. They tended to be very market based and nationalistic.

As an example, in the United States, many years ago we had the NMTBA, which is the National Machine Tool Builders Association. We also had ANSI, the American National Standards Institute. and most recently ASME, the American Society of Mechanical Engineers.

In Europe, they have ISO, which is the International Organization for Standardization and in Britain, the BSI, or the British Standards Institution. In Germany, they have VDI or DGQ, which is basically a grouping of German engineers.

In Japan, they have MAS and JIS, the Japanese Machine Tool Builders Association Standard and the Japanese Industrial Standard.

You might ask yourself why specifications are needed. Well, short of actually buying and trying out a machine, specifications are really the one and only way to compare different products and compare expected performance.

Not all Specs Are Equal
What you need to be careful of is that not all specs are the same, nor do they even provide comparable information about a machine. So, what is the reliability of the data and the technique or standard used? That’s a lot of what we’re going to talk about today. It’s really vital to understand this in order to make decisions such as what kind of accuracy and repeatability can I expect as I develop my part process, cutting speeds and speeds that are critical for cycle time estimation essential for capacity planning, and other aspects that are very important to estimate profitability or cycle times of a job.

One thing that’s important to remember about specs it that they’re very expensive and difficult to maintain. Also, machines were being shipped to markets not native to the original manufacturers’ country. Because machines are being consumed globally and weren’t necessarily built to the specification of the foreign country the machine was shipped to, standards can be confused. And the other thing is, we really didn’t have the emergence of global specifications, so most builders still utilize their native “market-based” specs for building and evaluating machine tools.

What does that mean to you as a buyer? Well, you can be faced with different machines that are built to non-comparable specifications. What you need to be able to do is estimate how to compare how one machine will perform compared to another. It’s critical that you understand and can fairly and factually analyze one spec against another for your particular application.