CNC Prototype Machining costs vary depending upon a number of facts and one of them is the time required to manufacture the parts. It can have a greater impact on cost than materials, setup time, or finish style. Geometry and tolerances also affect the quantity and kind of machines necessary and the skill level of the machinists required to operate them, all of which affect prices.
The following are ten ideas to assist you in optimizing your designs and making more cost-effective choices for your next CNC Prototype job.
1. TAKE CARE WHILE MATERIAL SELECTION
While the raw material cost may be inexpensive, if it is difficult to manufacture, it may cost more than slightly more costly but simpler to produce the raw material. By and large, softer materials require less machine time and maybe cut with less expensive equipment. Hazardous materials that necessitate more safety procedures might significantly increase manufacturing costs.
2. MATCH QUANTITY WITH TURNAROUND TIME
Prototype Machining is typically the most cost-effective method of producing prototypes in numbers less than 10,000. The more the quantity produced by a CNC milling machine, the lower the cost per unit. Costs are also affected by the speed you want components: parts delivered in a few weeks will be less expensive than parts delivered in two to three days.
3. CONDUCT A THOROUGH EXAMINATION OF FINISHES
Surface finishing and other treatments, including heat treatment, specialty coatings, and anodizing, add to the project’s cost and should be carefully considered. Multiple finishing procedures or surface finish types on a single component also add processing steps and, therefore, expense.
4. AVOID COMPLICATED PART GEOMETRY
The dimensions of a part, particularly its size and complexity, significantly impact its cost. Larger components require more material. Complex, highly complex parts need several processes and, in some cases, multiple machines, increasing programming, fixturing, and setup expenses. Certain complicated items, such as those requiring operations on many sides, may be more cost-effective to manufacture if planned as distinct components that are then put together after machining.
5. AVOID WALLS THAT ARE TOO THIN
Parts having excessively thin walls — typically less than 0.794mm (1/32 in.) — are not suitable for CNC Prototyping. Thin walls can induce deformation, making tolerances difficult to maintain. Additionally, they can generate chatter, reducing machine rates. Both result in increased machine and operator time expenses. Other production processes, such as sheet metal fabrication, may be more cost-efficient for building walls thinner than this requirement.
6. KEEP INTERNAL CAVITIES TO A MINIMUM
Parts having deep interior holes, sometimes referred to as deep pockets, illustrate how part shape influences the cost of machining time and material amounts. These designs may take several hours of machining to remove sufficient material to form the cavities, resulting in waste material and difficulties removing chips.
Additionally, the lengthy, thin cutting instruments necessary to produce these holes are brittle. The recommended practice is to keep the length of the part to a maximum of four times the depth of the part.
7. PRESERVE INTERNALLY ROUNDED CORNERS
Allow machining equipment to perform what they currently do automatically to guarantee your design does not slow them down. Internal corners are automatically rounded by tools such as milling cutters and end mills. The larger the radius of the corner, the less material the tool needs to remove, resulting in fewer passes. To reduce the length-to-diameter ratio of inside corner radii, a narrow-cornered tool setup (ie, 3:1 length-to-diameter ratio or more) has to be used in addition to extra passes. This leads to longer machining time and tool changes. Additionally, you may save machining time and tool changes by ensuring that all internal corners have the same radius.
8. MINIMIZE EXCESSIVE TOLERANCES
Not every surface of a design requires tight tolerances, and an excessive number of unnecessary ones increases the overall cost of the part. Typically, numerical callouts are necessary only for surfaces and features that are very important to the function of a part, such as those that connect with other parts. Minor features can be machined to a tolerance of +/-0.0127mm (+/-0.005 in.).
9. USE REGULAR DRILL AND TAP HOLE SIZES
A design that takes advantage of conventional tap holes and drill diameters can save money in various ways. Costs associated with tap holes can be increased by both the tap size and the tread depth. Threaded holes less than 2-56 in diameter will need manual tapping, which will add time and labor expenses, and should thus be avoided. It is rather common to find sizes to the nearest one-hundredth of an inch, for example, 1/4″ or 1/8″ (or the same with millimeters, such as 2mm or 1mm).
10. ASCERTAIN DESIGN ACCURACY
Consult an expert machinist or engineer throughout the design process to verify the correctness of your CAD designs. It may cost you more in the initial stage, but it will save you money in the long term. Incomplete or incorrect drawings might result in producing your item twice to achieve the desired result, adding time and expense to your project.
Utilize Reliable Computer-Aided Design (CAD) Software for Your Work
The two critical factors are simplicity of use and technical expertise. As a result, you may specify the prototype’s shape, volume, and size. AutoCAD, CATIA, SolidWorks, and Civil 3D are the most widely used and well-known CAD programs.
Consider Creating a Checklist for Your Design
Before you begin designing, you should create a checklist of the elements you wish to include in your prototype. Having a list will help you avoid making design blunders.
Avoid Complicated Drawings
Assemble clearly understood representations of the material’s characteristics using figures, symbols, and images. Complicated drawings make the design more difficult to comprehend.
Verify the design’s quality
After you’ve completed your design, double-check it against the characteristics listed in your checklist to identify any omissions or additions. After that, you may make any required changes before completing your design.
Similarly, engaging a competent manufacturer throughout the design process might assist you in avoiding overly expensive or difficult-to-machine components.
CONCLUSION
Manufacturers may now perform complicated operations simply and effectively thanks to the arrival of Prototype Machining. The main process benefit is helping to create prototypes, which it does exceptionally. This article discusses CNC machining in prototype production, its requirements, and some design recommendations for the CAD file. We trust you have gained some knowledge about CNC rapid machining. Remember, you can rely on us for the best CNC Prototype service.
