Festool eccentric sander in the test lab

Passion with punishing standards

The Festool testing department is proving the machines to the breaking point

Festool employees love their products. In the testing department, they must make the machines toil to breaking point with the same passion. This is all done for the benefit of the products, and in particular the customers, explains Gerhard Grebing, head of testing, in an interview.

Gerhard Grebing

Head of test department

Gerhard Grebing is the head of the quality management at Festool. He answers all the questions about the testing department.

In the automotive industry, vehicles have to travel many millions of virtual and real kilometres before they are brought to market. Is it the same for Festool machines, too?

It is very similar. Here at Festool, the machines don’t travel any distance but they do undergo tens of thousands of hours of testing under extremely high loads. A range of very different tests are conducted before market launch: a sander that is potentially used in two-shift operation for three years must still have the same level of performance as in the beginning. With a compound mitre saw, the double laser line must still be in the same position after 5,000 working hours. Nothing irritates a professional craftsman more than when his tools leave him high and dry. And that’s precisely what we want to rule out.

Testing the Festool products in the test department

What conditions are the Festool devices subjected to in testing?

In the dust chamber, for example, sanders are operated in almost inhuman conditions and covered with dust. In the drop test, a cordless screwdriver is dropped onto a metal floor from a height of more than two metres, until it breaks – or not. We also use a compound mitre saw to saw a concrete block, which nobody would seriously do.

All this is done for the benefit of the customers?

That’s right. Our machines are all known for being capable of doing a slightly better job and lasting significantly longer than comparable devices on the market. That is our top priority. And that is precisely what we ensure with our extensive series of tests and trials. Besides robustness and durability, the health of users is also a major concern for us.

So the machines have to withstand more in these extreme stress tests than they would when used by customers later?

The quality goals we want to achieve are very high. Of course, there are the guidelines and standards of the International Electrotechnical Commission (IEC). The requirements laid down there are an important foundation, but in many cases we even go beyond these. It is important for us that we not only measure the performance values but that we also test how a machine feels. For us, it’s always about touching, too. In the acoustic chamber, for example, it’s not just about reducing the volume but also reducing individual frequencies which, whilst they may not be loud, are extremely unpleasant. We filter out and minimise these frequencies.

Testing of the Festool eccentric sander in the acoustic cabin

You have had joint responsibility for quality management at Festool for some time now. You have also been head of testing for two years. What is the difference?

Quality management is first and foremost about avoiding risk and preventing errors – starting with product development, but also for existing products, we test and check constantly. In testing, we see ourselves more as enablers. Somebody comes to us with an idea, no matter how outlandish it seems. We realise the idea very quickly in a first step in the form of a sample. In this way, we find out whether the idea can capture the imagination. It is not uncommon for ideas for redevelopment or further development of a product to come straight from the customer, even. Our technical experts in the development department themselves know exactly what is currently technologically feasible and what will be feasible in the near future. Technical innovations often come from this area, too.

A Festool eccentric sander in the acoustic cabin

So that means there are a lot of threads diverging from and converging on the testing department then?

We are a team of more than 50 people here, each of us with different skills and experience. Some have a background as professional craftsmen, others come from the field of engineering. It’s incredibly fun to solve problems together and to get things off the ground. It is our aim to get even faster and better at this.

For testing, does this mean faster but in no way less careful?

Correct. That is something we cannot afford. However, we also cannot carry out three-year cycles of testing before a product comes onto the market. Our mission is to work fast and extremely carefully! We have developed special test procedures for this, which reduce the product’s life cycle to just a few days, so to speak. We really go right up to the limits and beyond. And not just in a virtual sense but in a very real sense. This is the only way we can guarantee that our tools will be able to do what we and our customers expect of them later in everyday use.

What appeals to you about your work in particular?

I think our work resembles that of an extreme mountain climber, in a way. He must think about every little detail and take every eventuality into account to achieve something great. If he is not careful enough at one tiny point, it can have fatal consequences. Of course, it isn’t a matter of life and death for us. But we manufacture machines that must function both in minute detail and on a large scale. Every single one. That is our responsibility. To the company and our customers.