1. Common Causes of Unstable Milling Machine Operation
(1) The table rail has excessive clearance, which can lead to uneven movement and poor cutting performance.
(2) The spindle bearings are worn or loose, causing the main shaft to vibrate or wobble during operation.
(3) There is a significant gap between the small neck at the right end of the milling cutter bar and the hole in the machine bracket. This can result in instability and vibration during the cutting process, affecting the quality of the cut.
2. Effects of Built-Up Edge on Cutting Tools
During machining, a small piece of metal can adhere to the cutting edge, forming what is known as a built-up edge. This hardened layer is difficult to remove and significantly impacts the surface finish of the workpiece. To minimize this issue, consider the following methods:
(1) Regularly use an oilstone to sharpen the cutting edges, improving the surface finish and reducing friction between the chips and the tool.
(2) Adjust the milling speed—higher speeds can increase the cutting temperature to around 600°C, softening the chip base and allowing it to be removed more easily, thus preventing built-up edge formation.
(3) For low-speed milling, use a larger rake angle; for high-speed operations, a smaller rake angle is more effective.
(4) Always apply cutting fluid, except when using hard alloy tools at high speeds where it may not be necessary.
(5) Reduce the feed rate and minimize the side cutting offset, especially when using carbide tools.
3. Impact of Workpiece Material on Surface Finish
When milling non-ferrous metals, the material's softness and low resistance make it challenging to achieve a bright surface finish. In such cases, increasing the rake angle and decreasing the relief angle (for cemented carbide tools) can help improve the appearance of the machined surface.
This article was originally published by Xiangyu Machine Tool on June 5, 2013.
Europe Type Heavy Duty Industrial Caster
Europe Type Heavy Duty Industrial Caster
Europe Type Heavy Duty Industrial Caster
Ningbo Mywin Caster Co., Ltd. , https://www.mywin-caster.com