Quick Answer For many conventional CNC-drilled holes, a depth-to-diameter ratio of approximately 3×D to 5×D is a practical starting point for design review. Here, D means the drill diameter. For example, a 5 mm drill producing a 25 mm hole has a ratio of 5×D. This is a planning guideline, not a universal [...]
Quick Answer Standard drill sizes can reduce the cost of machined holes because they are more likely to be available in a supplier’s existing tool inventory. Using a commonly stocked drill can reduce: Special-tool purchases Tool-change time Setup complexity Programming effort Quotation uncertainty Replacement-tool delays This does not mean every hole should be [...]
Quick Answer Undercuts justify custom tooling in CNC milling when the feature is functionally necessary, cannot be redesigned without compromising the part, and will be produced in enough quantity to support the additional tooling cost and setup work. For a one-off prototype, redesigning the geometry or adding a standard relief is often more [...]
Quick Answer External corner radii should be designed to remove sharp exposed edges, reduce stress concentration, improve tool access, support safer handling, and match the part’s functional requirements. The correct radius depends on the material, part size, machining method, available tooling, assembly conditions, and whether the edge is structural, cosmetic, or used for [...]
Quick Answer Delrin parts can be designed to minimize dimensional instability by keeping wall thickness uniform, avoiding heavy unbalanced sections, adding generous radii, controlling moisture and temperature exposure, using realistic tolerances, and planning machining and inspection around material movement. A 3D model is useful, but a complete drawing should also define critical dimensions, [...]
PEEK is often considered when a metal CNC component becomes too heavy, too conductive, too prone to corrosion, or unsuitable for a specific working environment. As a high-performance engineering plastic, PEEK can offer a useful combination of strength, thermal stability, chemical resistance, low friction, and electrical insulation. However, PEEK should not replace metal automatically. [...]
Free-machining stainless steel is often selected when a CNC part needs the appearance and corrosion resistance of stainless steel, but also needs better machinability, shorter cycle time, and more stable chip control. For many precision CNC components, material selection is not only about strength or corrosion resistance. It also affects tool life, machining cost, [...]
Duplex stainless steel is valued for its combination of strength, corrosion resistance, and durability. It is used in demanding environments where ordinary stainless steel may not provide enough mechanical performance. However, duplex stainless steel is not machined the same way as mild steel, aluminum, or even many standard stainless steels. Its higher strength, lower [...]
17-4 PH stainless steel is widely used for precision CNC components that require strength, corrosion resistance, hardness, and dimensional control. It is stronger than many common stainless steels and can be heat treated to achieve different mechanical properties. For custom CNC machined parts such as shafts, spacers, pins, clamps, bushings, brackets, adapters, and load-bearing [...]
Pure aluminum is soft, ductile, and easy to form. These properties are useful for many applications, but they also create a common machining problem: built-up edge. Built-up edge happens when aluminum material sticks to the cutting edge of the tool during machining. Once material starts welding to the edge, the tool no longer cuts [...]
