Plastics Learn more about the most common CNC plastics ABS Common lightweight

Plastics learn more about the most common cnc

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Plastics Learn more about the most common CNC plastics ABS Common, lightweight thermoplastic materials with good mechanical properties and excel- lent impact strenght. Easiest-to-machine engineering thermoplastic with high stiffness, excellent frictional charac- teristics and good thermal stability. POM (Delrin) Excellent impact strenght, thermal resistance and thoughness. Can be colored or transpar- ent. Suitable for outdoor applications. Polycarbonate (PC) High-performance engineering thermoplastic used in the most demanding applications. PEEK General purpose engineering thermoplastic with all-around good mechanical properties and excellent chemical resistance. Nylon > PEEK > Delrin > Nylon 6 > PC > Standard ABS
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29 Bead blasting adds a uniform matte or satin surface finish on a ma- chined part, removing all tool marks. Bead blasting is mainly used for aesthetic purposes, as the resulting surface roughness is not guaran- teed. Critical surfaces or features (like holes) can be masked to avoid any dimensional change. Extra cost: $ Surface finishes are applied after machining and can change the appearance, surface roughness, hardness and chemical resistance of the produced parts. Below is a quick summary of the most common finishes for CNC. Surface finishes Find out more about surface finishes Bead blasting As-machined parts have the tightest tolerances, as no extra operations are performed on them. Marks following the path of the cutting tool are visible though. The standard surface roughness of as-machined parts is 3.2 μ m (125 μ in) and can be reduced to down to 0.4 μ m (16 μ in) with further operations. Extra cost: None As-machined Powder coating adds a thin layer of strong, wear and corrosion resis- tant protective polymer paint on the surface of a part. It can be applied to parts of any material and is available in many colors. Extra cost: $$ Powder coating + Strong, wear and corrosion coating for functional applications + Higher impact resistance than anodizing + Compatible with all metal materials + Tightest dimensional tolerances + No added cost (standard finish) - Cannot be applied to internal surfaces - Less dimensional control compared to anodizing - Not suitable for small components - Visible tool marks Pros Pros Cons Cons + Visually pleasing matte or satin finish + Low-cost surface finish + Available in different coarseness - Visible tool marks Pros Cons
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30 Pros Anodizing adds a thin, hard, non-conductive ceramic coating on the surface of aluminum parts, increasing their corrosion and wear resis- tance. Critical areas can be masked to retain their tight tolerances. Anodized parts can be dyed producing a smooth aesthetically pleasing surface. Extra cost: $$ Anodizing (clear or colored) + Durable, visually pleasing coating + Can be applied to internal cavities + Can be colored to any Pantone tone - More brittle than powder coating - Only compatible with aluminum and titanium Pros Cons Hardcoat anodizing produces a thicker, high-density ceramic coat- ing that provides excellent corrosion and wear resistance. Hardcoat anodizing is suitable for functional applications. The typical coating
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