10 Tips for Reducing The Overall CNC Machining Cost
How to cut down the whole cost in the CNC machining process? In this article we will show you 10 tips to reduce your manufacturing costs of CNC machined parts. Experience shows that the machining time on the CNC machine is usually the biggest cause of costs. The costs for processing exceed both the material costs, the set-up costs as well as the costs for surface treatments such as anodizing.
The secret of low production costs
What therefore is the key to low production costs? Fundamentally, you should make sure that your part is processed on the system as quickly as feasible.
The quickest way to speed up processing is to concentrate on designing for manufactureability. The quicker the machining process is and the more economically individual components can be produced, the more developers and engineers optimise their ideas in terms of manufacturability.
Here are 10 tips of CNC machining cost reduction to keep in mind for your next project:
1. Optimal design of the cutting radius
The corners of a milling contour automatically have radii when being machined using a CNC milling machine. It is very difficult and expensive to create a rectangular pocket without a radius using, for instance, eroding technology.
You must take your component's milling cutter radius into account while designing milled parts. The larger you design the radius, the larger the cutter diameter you can use.
The surplus material can be taken out faster with the use of a bigger cutter. However, a smaller cutter must be used, which requires removing the same material in more steps, in order to achieve a small corner radius. In order to maintain low cutting forces and prevent tool breakage when using a small milling cutter, the feed rate must also be decreased.
An end mill's L:D ratio of 3 to 1 is typically advised for an ideal design that is acceptable for production (L = mill length, D = mill diameter). It is recommended to always employ the same radius wherever possible in order to reduce the need for frequent tool changes and to keep the complexity of the machining low.
2. Make the right tolerance
Tolerances should only be specified in your production drawing as tightly and broadly as necessary. Do not unnecessarily tighten the dimensional tolerance if a tighter tolerance has no benefit for the functionality to come. It is sufficient to state the general tolerance in accordance with DIN ISO 2768 in the title block of the design if you do not give any additional tolerance values for a dimension when dimensioning.
3. Avoid deep holes
Producing parts with deep pockets and large bores is expensive and difficult. Deep machining calls for delicate instruments that deteriorate more quickly. If traditional machining techniques like turning, milling, or drilling are no longer feasible, the maker can alternatively move to the extremely expensive eroding manufacturing method.
4. Make thin-walled areas more solid
It is challenging to clamp and machine thin-walled pieces. Because of their limited stability, thin-walled constructions make tools and workpieces swing more quickly. The cutter and clamping jaws may easily crush materials with thin walls. As a result, expensive or flawed parts are produced. Avoid using wall thicknesses less than 1.0 mm when making CNC parts.
If thin walls are necessary, another option is to think about whether sheet metal forming may be used to create the part.
5. Use standard measurements.
Try to use conventional dimensions when creating your bores, countersinks, threads, and even pin holes (see DIN, ISO...). This ensures that standard and inexpensive drills, countersinks, thread cutters and countersinks can be utilised. Tools created to order are pricey.
6. Improve the design of the threads
The price of your component depends on the quantity and depth of the threads. Try to have as few threaded holes as possible, and as a general rule, a maximum thread depth of 3xD (where D is the thread diameter) is sufficient
For instance, you shouldn't drive an M5 screw deeper than 15 mm. As a general rule, it also holds true that it is simpler to manufacture larger threads.
7. Select the appropriate material
Use the material that is best for your component. Use a free-machining aluminium alloy that can be easily machinable if strength and other factors permit. (DIN EN 573/Table of Aluminum Alloys) Compared to high-strength steel, the softer aluminium can be machined significantly more quickly.
There are several alloys that are easier or harder to process, even with steel. A typical free-cutting steel is also recommended here.
8. Preserve simplicity
Keep your component's outlines as straightforward as you can. In order to reduce the number of times the component needs to be re-clamped during machining, design your part so that only a few sides need to be machined.
9. Prevent using several surfaces on one part.
A component having several surfaces costs more to make. Only with greater effort are other chemical and electrolytic surface treatments conceivable.
10. Mass production benefits cost reduction
Even though the most recent CNC machining centres can already be set up and clamped in parallel, ordering more will result in a greater cost reduction for the machining process. Imagine what would happen if you ordered 10,000 pieces as opposed to only 100! The expense of setup, programming, and setup is then divided over a large number of components. For the manufacturing company to be able to supply the parts more affordably, it is worthwhile to optimise the machining process in detail when producing bigger quantities.
Cost reduction is a conscious strategy. From the beginning of the design of the parts, it is necessary to follow the most reasonable and cost-saving plan, not only to achieve the best product effect, but also to have sustainable competitiveness. Exzellenc CNC has many years of experience in CNC machining, machining various complex parts, which can not only ensure quality, but also produce results that satisfy our customers, which is what Exzellenc has been pursuing.