Time to read: 5 min
If you’ve ever designed and 3D printed a part that required high dimensional accuracy, you were probably disappointed with the outcome. Maybe a bolt didn’t fit into a 3D printed hole, or a 3D printed bracket didn’t fit into its intended recess. Whatever the dimensional intention, it’s likely that the 3D printed part didn’t serve its function because the 3D printer lacked the dimensional accuracy to manufacture it as designed.
Does that mean you need to change your manufacturing process? Not necessarily. Sometimes3D printing零件是正确的选择，但是某些功能需要通过后处理进行微调。如果您要生产低到中等数量，或者即使在制作零件中，则使用3D打印作为主要的制造过程也很有意义。
Instead of changing your manufacturing process entirely or designing a complex, manual post-processing workflow, this article explores the benefits ofCNC machiningyour 3D printed parts. Doing so can improve dimensional accuracy, reduce waste material, and save time and money in your manufacturing operation.
Improving Dimensional Accuracy & Precision
CNC Machining can achieve a much higher degree of dimensional accuracy and precision than 3D Printing due to根本差异两者之间的生产流程。如果你哈ve certain features on your 3D printed part that need to be manufactured exactly according to your specifications (high accuracy) and/or you need certain features to be manufactured exactly the same every time (high precision), then CNC machining your 3D printed part in post could be a great option.
What kind of features on your 3D printed part might require improved accuracy or precision? Here are a few examples:
- Holes.圆形通孔和圆柱形休会es. A hole, of course, is typically meant for something to fit into it or pass through it. However, 3D printed holes are often slightly deformed or dimensionally inaccurate by as much as 0.5mm depending on the machine and 3D printing technology used.
- 零件的边缘/范围。Dimensional inaccuracies and lack of precision in 3D printing often make fitting 3D printed parts into assemblies challenging. If your 3D printed part is intended to fit somewhere, particularly in a tight recess, CNC machining the edges to trim it exactly to your specifications could be the key to making the part fit!
- Recesses in part.Similar to edge finishing parts to get a good fit in assemblies, CNC machining in post can create accurate recesses in parts that are needed to provide the fit you’re looking for. This process can be particularly helpful for product design, as products often rely on snap-fits or interference fits to keep unique parts of the product together as a unit.
In order to incorporate CNC machining into your 3D Printing workflow to improve dimensional accuracy and precision, you need to consider a few design points. First, you need to make sure that the CNC mill can reach all desired features and that nothing obstructs the tool path. Also, you need to build excess into the part so that the CNC mill can cut away material to meet the part’s spec. Finally, build in flat surfaces for fixturing if possible — doing so will enable the CNC mill to achieve maximum precision and mitigate potential failures in the manufacturing process.
Reducing Waste Material and Overall Material Cost
从3D打印到零件的CNC加工完全切换可能会增加生产成本。混合方法可以最大程度地减少制造成本，同时提供完全适合您需求的零件。
In general, 3D printing materials cost less than stock for CNC machining, so using 3D printing for the bulk of your part is likely to be significantly cheaper than machining a part from scratch. Furthermore, since 3D printing is an additive method, it produces much less waste material than CNC machining — which lowers material cost and makes for a more sustainable operation. And since lean, sustainable manufacturing operation is the way of the future, using a hybrid approach can be an effective way to stay ahead of the curve!
避免手动后处理
Often dimensional accuracy is achieved in 3D printed parts by manually drilling, sanding, or carving parts to achieve the dimensions and fits that are required. This takes a great deal of time and attention to detail, and so is expensive and inefficient. By eliminating manual post-processing entirely, CNC machining in post can significantly reduce the time and money it takes to produce a part.
Let’s consider an exemplary case study:
- You have a 3D printed part with a dozen 0.25” mounting holes (see images above for reference). 200 parts need to be shipped out within 1 week.
- 需要1位成员6分钟才能钻出零件上的所有孔，以使紧固件适当地安装。为了在本周结束时准备好零件，该人将需要花费1200分钟或20小时钻孔零件才能达到截止日期。
- 另外，工程师花了4个小时的工作来准备CNC机床路径以钻出零件。CNC机器可以在2分钟内钻出所有孔，将整个后处理时间从20小时减少到7小时以下。总而言之，与20小时手动后处理相比，CNC后处理工作流程不到11小时，从而使生产过程更快，更有效。
剪切手动后处理是一种确保制造成本较低并每次按时生产零件的肯定方式。CNC加工您的3D打印零件可以帮助您忠于时间表，同时释放人力资源来完成更重要的任务！
Conclusion
3D printing and CNC machining are two vastly different manufacturing technologies with vastly different strengths and weaknesses. However, if you utilize them together, you can develop a manufacturing method that delivers the strengths of both and the weaknesses of neither. A hybrid approach can manufacture your part with high dimensional accuracy, low material cost/minimal waste material, and without painstaking manual post-processing.
FICTIV目前没有为3D打印零件提供CNC加工服务，但是我们的CNC加工服务可以为其他塑料材料提供的公差与.05mm一样紧。而且，虚构提供了通过使用不同类型的添加剂制造来提高维度准确性的方法。SLA（立体光刻），SLS（选择性激光烧结）和MJF（多喷射融合）可用于功能原型甚至最终用途的生产零件。虚构可以帮助您使用这些3D打印过程以及更多内容来解锁创新，因此请注册并立即开始！
