Quality Control of CNC machining-how to avoid quality problems in manufacturing of cNC machine tools

In the context of small-batch or on-demand production, this is a topic that is rarely addressed, and that topic is quality. Mechanical designers how to select process specifications to ensure they get the exact quality and output they want for prototypes and small batches of products. Let’s begin to classify  the discussion into two main points.

 With regard to the definition of quality

first, it is necessary to review the definition of quality, especially the different definitions of quality by some people, especially the definition of quality by designers and the division of quality by manufacturers. You can see how important these differences are in the design and manufacture of products.

Requirements and specifications

second, we will check all requirements and specifications for consideration, you may be designing a product for manufacture, and check for some tips and tricks on what you should and should not do to ensure you get the right quality, the product you want.

DFM

DFM stands for manufacturing design. Whether you work in CNC machining, 3d printing or injection molding, if you're designing parts, you have to be clear about the limitations of the technology and what designs are or are not suitable for the technology. In NC machining, you will encounter many sharp corners, you can achieve the tolerance, so your parts more complex the more you need to learn. So the manufacturer can succeed, not fail.

Standard Request

Second, for DFM, if you are a designer, it is necessary to use standard requirements. When you want to bring a product to market in a quick and consistent way, sometimes less is more in terms of demand. A manufacturer has to process up to 200 different orders, 200 different CNC parts every day, they have to program, they can't always come up with a custom process for this part, they have a new design, programming on their CNC machines. They will need to establish standard operating procedures, consistent output, and they can form a specific process. The best example is when you have CNC machine parts in aluminum, because the machine is a very consistent and very clear standard that defines Surface roughness, even a plastic product. If designers in CNC machine parts on the choice of machining, they almost certainly the appearance of products and manufacturers, this is the manufacturer and designers of the link. Manufacturers also know that when designers choose machines, they have expectations about the process, but what the result will be, so they choose a standard requirement that everyone can easily understand, allows everyone to quickly define and adjust specifications.

Context

The third point is the background. Context means the context of the part, meaning what you’re going to do with it, and what products it's going to be integrated into. This is very important information for the manufacturer. Some designers may overlook this because they think they are DFM educated and know all aspects of CNC machining, but there is always a point where manufacturers will face a minor conflict. If we take a concrete example of an aluminum part, and the designer chooses to polish the surface by hand, the manufacturer knows exactly what the polishing compound will use, what Surface roughness, and so on. This process is standardized, and designers also choose to combine it with tight tolerances, which is usually when you have a combination of two standard requirements, some conflict may occur. That’s what context is. It’s important. For polished aluminum parts with strict tolerance, some parts of the manual polishing is not conducive to the improvement of tolerance. Or you can spot the problem at the DFM stage, when you place your first order with the manufacturer, and they may spot the discrepancy or minor conflict, but they probably won’t. In case they have to meet the deadline, they may not have time to ask the designer for the information they need to resolve the conflict. So if you can tell them, as a designer, that when given the command, this piece will be used on the outside of the car, and perhaps the width portion is the most critical tolerance, then they may have been able to consider some solutions, when I touch you. In this case, context is important, because if you don’t have a context, the manufacturer will detect a conflict, and if they have a tight deadline, they will make a judgment, or they may ask you for more details about the end user. Because they lose, they find conflicts, which can take a long time, especially in on demand situations, where they have a lot of custom orders to make. So the environment is the key, even if you think you have chosen the standard requirements, the environment will not hurt you.