A new hammer drill made by DeWalt – a worldwide developer and manufacturer of professional power tools, and part of the Stanley Black & Decker corporate group – has a plastic housing that is a combined part, enclosing both the electric motor and the mechanical drive, and replaces a previous metal component.
The engineering plastic used for the housing is BASF’s Ultradur B4300 G6, a PBT (polybutylene terephthalate) material.
The new part replaces two separate housings, one of which – the gear housing – used to be made of diecast magnesium. The plastic housing now accommodates the electric motor and the gear along with the chain drive. It has to be extremely accurate dimensionally, with the axes of the gear components remaining exactly parallel even at high operating temperatures and in humid environments. A weight saving is claimed from replacing the metal.
Reimund Becht, a project manager at DeWalt, commented: “Doing away with an additional metal part simplifies inventory and logistics, while the integration of key functions such as snap-on fastenings eliminates the need for screws and reduces assembly time. Moreover, cut threads are no longer needed. Manufacturing cost is reduced since, by contrast with metal, plastic parts … do not have to be mechanically reworked.”
DeWalt uses other BASF engineering plastics elsewhere in the new hammer drill. Ultramid A3WC4, a carbon fibre reinforced polyamide, is employed for the very rigid connecting rod which joins the piston to the crank wheel. The yellow and black exterior housing parts are made of impact-resistant Ultramid B3ZG6, and the components close to the motor that come into contact with hot and electrically live parts are made of Ultramid A3EG6 or Ultramid A3EG7.
DeWalt itself manufactures the plastic parts of the hammer drill hammer at its plant in Usti/Trmice (Czech Republic).
The new drill is already on sale in Switzerland, and is being rolled out throughout Europe this month.