CNC Machining Materials

Polycarbonate

At a glance

Processes

CNC Mill
CNC Lathe

Lead Time

As fast as 2 days

Colors

Clear, black

Tolerance

With drawing: as low as +/- 0.005 mm
No drawing: ISO 2768 medium

Price

$

Applications

Light pipes, transparent parts, heat-resistant applications

About the material

Polycarbonate (known also by the abbreviation PC) is one of the most common plastics used in manufacturing. Famous examples of the material are first-generation MacBook laptops, safety goggles, and optical disks.

Polycarbonate is heat-resistant, impact-resistant, flame-retardant, and one of the most recycled plastics in the world.

Material Properties

Tensile Strength

8,000 PSI

Elongation at Break

110%

Hardness

Rockwell R120

Density

1.246 g/㎤
0.045 lbs / cu. in.

Maximum Temp

180° F

McMaster Part Number

8574K321

Material Finish

Polycarbonate has a transparent milky-blue look in its natural state, but is also available in black. Both colors have a glossy finish, and are relatively prone to scratches. Anti-scratch coatings and vapor polishing are available as custom post-processing finishes.

Design Recommendations

Min Wall Thickness

0.5 mm

Min End Mill Size

0.8 mm (0.03 in)

Min Drill Size

0.5 mm (0.02 in)

Max Part Size

1200 x 500 x 152 mm[(x,y,z] (mill)
152 x 394 mm [d,h] (lathe)

Undercuts

Square profile, full radius, dovetail profiles

Radii : Depth

Depth must not exceed 12x drill bit diameter.
For end mills, depth must not exceed 10x drill bit diameter.

Cost Saving Tip

To reduce costs, limit the number of part setups, the number of inspection dimensions or tight tolerances, and deep pockets with small radii.

Polycarbonate FAQs

Can you CNC polycarbonate?

Polycarbonate (PC) is a tough, transparent thermoplastic with high impact and heat resistance. Polycarbonate is one of the most commonly machined materials. is one of the most recycled plastics on the planet.

What is machine-grade polycarbonate?

Machine-Grade Polycarbonate is an amorphous thermoplastic, transparent and possessing high impact strength and exceptional dimensional stability. It is often used for structural applications where transparency and superior impact strength and rigidity are essential. Machine grade polycarbonate is stress relieved, making it ideal for close tolerance machined parts. Its low moisture absorption rate and its chemical resistance makes machine-grade PC extremely versatile as an engineering material and allows for its use in an abundance of industrial applications.

Is polycarbonate better than acrylic?

Polycarbonate is stronger than acrylic and has 250X the impact resistance of standard glass. Polycarbonate is ideal for highly demanding applications due to it’s higher resilience, as compared to acrylic. Acrylic is also easier to crack, while polycarbonate is easier to scratch.

What is polycarbonate plastic used for?

Polycarbonate is one of the most common plastics used in manufacturing. Its high strength and light weight are valued for making shatterproof windows, eyeglass lenses, CDs, DVDs, mobile phones, and more. It’s most famous examples of uses for the material are first-generation MacBook laptops, safety goggles, and optical disks.

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