It depends on the specific application and the machining requirements. Both Weldon holders and ER collet chucks have their own unique benefits and can be used for end milling operations.
Weldon holders are characterized by a flat, cylindrical shank that is inserted into the spindle of the machine, and they typically feature a clamping mechanism that tightens around the shank of the tool, providing a secure grip. They are commonly used in operations such as drilling, reaming, and tapping. The benefits of using a Weldon holder include:
Greater clamping force: The clamping mechanism of a Weldon holder can provide a higher clamping force than an ER collet chuck, which can improve tool stability and reduce chatter.
Greater precision: Because the clamping mechanism of a Weldon holder provides a more secure grip on the tool shank, it can help to improve the accuracy of cutting operations.
Higher speeds and feeds: Due to the increased clamping force, Weldon holders can allow for higher speeds and feeds than ER collet chucks, which can improve productivity.
On the other hand, ER collet chucks are specifically designed to hold round-shank cutting tools, such as drills, reamers, and end mills, and are used in a wide range of operations, including turning, milling, drilling, and grinding. They are known for their versatility, easy tool change and cost-effectiveness.
It's important to note that the choice between Weldon holders and ER collet chucks depends on the specific application and the machining requirements. Both have their own advantages and disadvantages, and the best option will depend on the type of tool being used, the material being machined and the machining conditions.