Issues needing attention in CNC plastic prototype processing

CNC processing of plastic prototypes and metal prototypes are similar, but there are also many differences. Because there are many types of plastics, different plastics are processed differently. When making CNC plastic prototypes, you need to pay attention to many details. Which details need to be paid attention to? Woolen cloth ?

First of all, plastics are a big category. Common plastics include PE.PC.PVC.ABS.POM.PMMA and so on. Material properties vary wildly, ranging from soft sponges to plexiglass, and polyacetal, which can partially replace steel. Because the material properties are different, the processing differs greatly.

The most common problems that occur when processing CNC plastic prototypes are breakage, cracking, collapse, and scratches. In the final analysis, the knife speed is wrong and everything is in vain. You cannot blindly trust the information on this matter, because the quality of domestic materials does vary. So be sure to try it out before actually processing it! It is best to trial-produce different batches of materials! What you get from another supplier will be completely different.

Another issue is the choice of knife. Don't expect that the metal processing knife will be OK if it directly dries plastic. The tools used for metal processing, plastics, and wood are still very different. If they are mixed, the knife will become a mess. For example, processing nylon materials is not like processing metal. When the knife is cut, the chips will fly everywhere. Instead, like sharpening a pencil, it wraps around the knife in circles. At first it just wraps around, but as the temperature rises more and more, it will melt. When you stop the knife at this time, you will find that there is a lump on the knife, and it will be difficult to pull it off if you handle it slowly.

The solution is to slow down, lift the knife more, and cool down more. When cooling, the coolant effect is not better than that of air gun blowing. Because metal processing chips are small, the residue can be carried away with the coolant. But the plastic ones look like nylon threads, and it’s impossible to wash them away in clumps.

Another problem is that there are often circles of corrugated lines on the machined surface. It is difficult to do surface treatment in this later stage. Metal parts can be polished with different sandpaper sizes. After sanding the plastic a few times, the entire surface of the sandpaper was covered with a layer of inexplicable paste. Golden Elephant sandpaper is not suitable for dry sanding plastics. Some harder materials can be treated with woodworking sandpaper and a sander.

CNC Processing of plastic prototypes is actually not difficult. The key is to choose different tools and processing methods according to the characteristics of different materials. CNC plastic prototypes can be processed in single pieces or in small batches, and their processing accuracy can generally reach 0.05mm. The accuracy is closely linked to factors such as machine tools, CNC systems, cutting tools, and cooling.

If you have any prototyping project, please contact us to get free quote: enquiry@abcrapid.com.