What is the material used for over-moulding on the handle of a drill?

The use of Thermoplastic Elastomer (TPE) or rubber for over-moulding on the handle of a drill is primarily due to its desirable properties, which enhance the functionality and user experience of the tool. TPE is known for its flexibility, durability, and resistance to various environmental factors, making it an ideal choice for applications where grip and comfort are important. The soft and rubber-like texture of TPE provides a non-slip surface, which enhances the user's grip, reducing the risk of slippage during use. This is particularly important for tools that are subject to torque and force, as it helps the user maintain control while operating the drill.

Furthermore, TPE can also provide shock absorption, which helps reduce vibrations that may be transmitted to the user’s hands during operation, contributing to greater comfort over extended use. The material's ability to be easily moulded allows for the production of ergonomic shapes that fit comfortably in the user’s hand.

Other materials like nylon, silicone, and polypropylene may not offer the same level of grip or comfort. While they have their own specific applications in engineering, they do not provide the combined benefits of flexibility, grip, and shock absorption that TPE or rubber delivers for the handle of a drill.