Ordering CNC machined parts might be marketed by various services as a simple procurement, just as easy as ordering stock online from suppliers like Grainger or Amazon. However, the fact is, CNC machining utilizes and requires specific, computer-programmed design that directs the machines involved to do the actual work. In this regard, the details have to be detailed in mechanical terms and specs. From there, the fabrication directions are then translated into programming code to apply in the CNC environment. So, given this technical step, a customer needs to be prepared to either provide the necessary details, or, have them professionally coded.
Complexity is the Norm
Expect to deal with complexity when engaging with CNC machining. Ordering any kind of CNC machining, even basic orders with 3-axis machining, requires a complex set of instructions that have to be scripted in a particular format for the machine computer to understand and apply the dimensions. However, even before scripting, there are other things to make sure are checked and taken care of first. They include the following.
Tolerances
If the part to be machined will be under any kind of load or pressure demand, it has to be able to meet specific tolerances in its shape and design. Without being provided these specifications, the machinist won’t know how to fabricate the part correctly, and it will fail when applied under real-time conditions. Tolerances not only refer to the details of shape but its strength as well. Precision can also make a big difference in how the part works with other assemblies as well. For example, a piston in an engine chamber will fall apart under the high speed of the rotations and movement if it isn’t exactly the right shape for the valve it moves within. Friction takes over, and then bad things happen. Tolerances matter. So, if they are needed, make sure they are clear and detailed for the machinist.
Surface Finish
A CNC machining task can easily include surface finishing if needed. In some cases, a rough finish is all that is necessary. However, in others, a smooth, mirror sheen may be necessary. Surfacing can be performed and provided down to the microscopic external layer, if needed. However, the machinist won’t automatically include this detail if it’s not specified. Polishing can take things even further, especially for very detailed applications where friction has to be at a minimum.
Study Your Materials
Obviously, a desired part should be produced from material that is strong enough to meet its purpose. Anything can be carved out of soft material, like aluminum or plastics, but that doesn’t mean it will hold up under any kind of strain. On the other hand, asking for a part made from extremely harder metal like tungsten might be overkill. Match the material to the job when specifying what you think you will need in the part design and fabrication. Don’t get caught in the trap of using a metal because it’s cheaper than the one that will do the job right.
Have Alternatives
Not every machinist will have one specific material in stock and, in some cases, alternatives can do the same job just as well. Study your materials for parts and be sure to be aware which materials can work as substitutes for your original choice. This will give your ordering detail flexibility and could likely drive down cost. If a machinist can only use one specific part which might be hard to find at the time, that can drive up cost significantly. Focus on flexibility within the same range of properties that you want the product to have. This, in turn, will give you an efficient value for your expense.
Keep the Service Available in Mind With Your Product Design
If you’re expecting to have a very intricate design on your part, anticipate who might actually be able to provide the CNC machining services. Not every machinist carries milling or turning equipment that can handle products that demand 5 or even 7-axis machining. While everyone in the industry can provide the basic 3-axis machining, the more complex a part, the smaller the pool gets for those who produce the work. You may find, with a very complex part, that you’re going out of state to find a service that can do the work, so plan accordingly if it’s needed.
Suffer Through the Prototypes
Don’t be in such a hurry to get to production. Allow for a one-off prototype at least once if not twice. Doing so can nail down very subtle issues that might get missed in the design and development process and won’t be apparent until the part is actually fabricated and examined for the first time. You don’t want a fatal mistake to be found for the first time when you’re unpacking a production run and there’s no recourse to fix it. While it might add to the cost of the project, prevention is a lot less expensive than damage control after the fact or an entire project loss.
Evden Enterprises has worked repeatedly with all types of project needs and part designs through the years. Covering projects ranging from rush jobs of unique gearing to specialized, complex products produced with the highest milling technology available, Evden’s technical team have the expertise that sets the CNC machining standard for everyone else in the industry. That comes from experience, robust technical knowledge, and access to the latest milling equipment available. Find out the difference in your next project working with Evden Enterprises on your part production.
