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Solve The Problem Of Poor Surface Quality Of CNC Parts

Nov. 20, 2019

For outsiders who are unfamiliar with CNC shop operations, once the chips stop flying away, the milling machine is dropped, and another precision machine part is introduced, they are likely to consider the final product to be accurate and compliant. Unfortunately, this is not always the case. In any CNC machining shop associated with this, the finished product is delivered to the customer until the finished product passes the inspection service process. CNC Precision Machining Parts must be sized to meet the tolerances set by the design, including thorough inspection of the finish of all machined surfaces. Often, parts may conform to specific dimensional specifications, but must be scrapped because the overall appearance and surface finish are not up to standard. Not only does this lead to aesthetic problems, but more importantly, it can have a negative impact on the function of the part.


CNC Precision Machining Parts


CNC Precision Machining Parts


Most importantly, in the final stages of the milling and machining process, the amount of work that must be sent to the waste bin is less than the desired result. CNC mechanics are born with attention to detail, are proud of their work, and want to see a complete project. Scrap parts due to surface finish problems may also be a real profit killer in the machine shop. Poor quality leads to increased costs, increased downtime, delayed delivery, and, in the worst case, lost orders. The problem becomes; how do mechanics and stores solve this problem? What should I do if the final result does not reach the expected level? The CNC Machined Spindles Shafts Factory below will lead you through some tips on how to use CNC milling machines to get the best surface finish.


1. Improve cutting tool speed

The measure of surface feet per minute (SFM) means that the contact time of the material with the cutting tool is reduced. This reduces edge build-up, resulting in poor surface finish and extended tool life. Tool failure is the main cause of damage to precision machined parts. Never estimate or guess the speed of your work.


2. Always clear / control chip

Clearing excess chips or stacking edges (BUE) and not allowing them to touch the workpiece during processing is a critical task and is the key to producing a high quality surface finish. Chips and BUE are prone to build up and can easily damage the surface finish of the cutting tool if not removed. Chip breakers, compressed air and the best solution, flooded coolant can be used to remove chips and BUE for better control and less scratch/damage of parts.


3. Roughing and finishing should use different tools

Do not use the same tool used for roughing to complete the part. Instead, use a small amount of roughing tools to remove most of the material, while retaining new, sharper tools and only for finishing passes. When used in combination with roughing or finishing tools, the tool insert's radius, rake angle, feed rate and blade material itself provide higher quality.


For laymen, once milling and machining are finished and the lead time is approaching, it is necessary to check the aesthetic appearance of precision machined parts. Regardless of the material, a thorough inspection of the work done is a key factor in the function of the part. Particularly suitable for aerospace and medical device manufacturing industries. Excessive chip and/or BUE, slower running speeds and improperly used tools are the main causes of surface finish degradation. Lack of machine maintenance, low coolant levels, poor settings, and CNC programming errors are also responsible for this. The techniques we offer are suitable for a wide range of machining operations, including milling, turning and grinding. If used consistently, the surface finish of the problem work should be greatly improved to achieve a satisfactory customer and reuse the business.


The above is the 5 Axis Precision Machining Service supplier introduced to the CNC parts processing surface treatment methods, I hope to help everyone.