Angle grinders are very universal and helpful tools. They can be used for cutting, grinding, and polishing many materials. On the other hand it is also very dangerous and aggressive. Trends analysis pointed the high demand for universal tools for light to medium work that does not require professional experience. Under these conditions, dremel brand and a group of tools designed for the layman by bosh (green series) are doing great, but their abilities and power are very limited. sFlex is designed for craftsmen, diy and hobby users. I designed it to give them the powerful, yet mistakes forgiving tool with the functionality and universality of original angle grinder.

The inspiration

I'm a hobbyist. I used the angle grinder many times in my life. I also have seen the accident when the grinder slipped out from the worker's hand and cut half of his palm. It is not surprising, that many people are afraid to use it. It is very unsafe and aggressive tool. In fact, angle grinder is one of the most dangerous tools. All around the world it is a cause of many accidents, also many fatal ones. This is not a good situation. Other motivation is also the limitation it causes - without the possibility to use the tool safely, creative people can abandon their ideas.

How it works

'sFlex' has two working modes. It can be used as a cutting tool or as a sanding tool. The blade is hidden in a cover. The cover is moving along the longer handle, but strong spring is closing cover if the user releases any of the handles. To start cutting, user have to pull the top grip towards, than saw blade comes out. If the user loses control, and sFlex falls out of his hand, the saw blade is covered automatically by the casing. The grinding mode works in similar way. In this mode the grinding wheel slides out of the housing through the bottom.

In the main body there is an engine and the battery, in the front part is an rotatable top grip for the second hand, and the transmission mechanism. Top grip is rotatable, so the angle can be adjusted to the needs. It makes the 'sFlex' also fully functional tool for both left- and right-handed users.

'sFlex' works with the same accessories as other conventional angle grinders that are available on the market.?

Stages of development

My main focus was on safety, then on the mental and physical comfort. I wanted to create a tool, where the effect of safety features on the functionality is reduced to minimum. I went through many models, and prototypes to develop the final package and simplify the construction. The assumptions were challenging. Angle grinder has two main modes of processing - with an edge of mounted disc/accessory (cutting), or with the bottom surface (grinding, polishing). Functional models helped me to develop a prototype of the mechanism that transfers rotation from the motor through the telescopic axis. This mechanism provides the ability to move the head (with a mounted disc) in two axes. The final design - in opposite to trends – was developed to make sFlex visually stable and secure, so that the user will not have the impression that the tool is aggressive and unpredictable.