Multi-tool (powertool)

Multi-tool is a common name for an oscillating Power tool powered by battery or mains. The name "multi-tool" is a reference to the many functions that this tool can perform with the range of attachments available. So far there are tools available to saw, sand, rasp, grind, scrape, cut and polish.

Use of an offset in a fitted blade allows the tool to cut flush with a surface. This is particularly useful when fitting flooring along a skirting board, cutting the skirting to allow the board to slide under for a neat finish. The small form of these tools and the ability to mount the blade/accessory in any orientation allows cutting in areas previously unreachable. The ability to cut a complex or precise recess without the need to remove the work piece from where is it fixed greatly increases productivity. Small and precise cuts are possible even on end grain, a small sliver can be easily removed from timber cut too long for a perfect fit.

The accessory is fitted to the tool by some mechanism which allows that accessory to be rapidly rotated back and forth (oscillated). This creates friction with the sanding attachments or rapid cutting motions with the saw and grinding attachments. The narrow angle of oscillation allows for precise control over the tool as it does not kick like a rotating tool can. The angle of oscillation creates increasing friction further from the center of the tool as these areas travel a greater distance. The increased friction is particularly apparent with the triangular sanding and grinding attachments which allow the operator to reach into corners and confined spaces, a feature unique to this type of power tool. The saw blade attachments use the angle of oscillation in the same way.

The oscillating blade will not clear swarf in the same way as a rotating blade so it is necessary to move the blade back and forth to clear built up sawdust and clear the blades.

Improvements in battery technology such as Lithium Ion have allowed for tools which can be small in size and weight but still perform well enough to compete with mains-powered equivalents while freeing the user from the restrictions of cables.