When you use custom 3D printing to make your new product or prototype, you will need to make sure your design is the best it can be. By doing this, you make sure that the model will look good and work well after it has been printed. On top of that, optimizing the design can help reduce the time and money needed to make the product. When you use CNC machining, you should also make sure the design is as good as it can be. The CNC quote should be as low as possible, after all. You will be able to do this if you follow the five tips below.
Avoid deep cavities
Besides that, you should also write down the size and depth of any holes. This is very important to do when making a new model for CNC milling because end mill tools can only cut a certain length. This is usually three to four times the diameter of the tool being used. You will get better results if you limit the depth of the cavities in your design to four times the diameter of the tool.
Don’t use a lot of little things
Even though you can add small details to your design, you shouldn’t do too much if you’re making it for CNC machining. You can add small details like holes and cavities to your design. But keep in mind that the diameter of these small features shouldn’t be bigger than 2.5 millimeters. If the number is less than 2.5 millimeters, machining is not only harder, but it also takes more time and costs more money.
Round the edges on the inside
If your design has at least some internal edges or corners, it is helpful to know the diameter of the cutting tool. This is true because you’ll have to think about this when you’re optimizing your design. This could make the surface finish a little less nice, which is a shame, but it is still possible to fix this potential problem. In fact, the surface finish will be better if you make the corner radius one-third as big as the depth of the cavity. Does your plan have a 90-degree angle? Instead of making the corner radius smaller, use a T-bone undercut.
Improve the drilled holes
CNC-machined parts can have tapped holes added to them. You can thread a bolt or screw this way, for example. Even though you could use an M2 thread size, it is better to use an M6 or larger. This will probably work out better. You should also think about the length of the thread. Most of the time, it is best to use a thread length that is three times the diameter of the hole. The least, though, is 1.5 times.
Try to build thick walls
If your design has walls that aren’t very thick, it’s very likely that they will vibrate when they are made. Also, if the temperature goes up, thin plastic walls may warp or soften. In other words, it makes it much harder to machine these parts with a high level of accuracy. You don’t want this to happen, so you should make sure that the metal walls are at least 0.8 mm thick. The walls of a plastic box should be at least 1.5 mm thick.