CNC Machining Materials

Acrylic

At a glance

Processes

CNC Mill
CNC Lathe

Lead Time

As fast as 2 days

Colors

optically clear, opaque

Tolerance

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

Price

$

Applications

tanks, panels, and optical applications

About the material

Acrylic is a scratch-resistant plastic, available optically clear or opaque. It is often used for tanks, panels, and optical applications.  It can be somewhat brittle in thin walled areas, so it is not recommended for delicate or complex geometries.

This plastic is also known as PMMA, an abbreviation of its full chemical name, polymethyl methacrylate, as well as by the trade names Plexiglas and Lucite.

Material Properties

Tensile Strength

8,000 PSI

Elongation at Break

6%

Hardness

Rockwell M95

Density

1.19 g/㎤
0.043 lbs / cu. in.

Maximum Temp

170° F

McMaster Part Number

8560K274

Material Finish

Acrylic is transparent or opaque (black, white, and a variety of colors) in its unfinished state.  Clear acrylic will take on more of a frosted translucent appearance when machined, though can be smoothed again to an optically clear state using various finishing methods.

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.

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