CNC Machining Materials

UHMW

At a glance

Processes

CNC Mill
CNC Lathe

Lead Time

As fast as 3 days

Colors

White, black

Tolerance

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

Price

$

Applications

Machine guards, liners in chutes and hoppers

About the material

Ultra-High-Molecular-Weight Polyethylene (or UHMW) is a hard plastic with a slippery surface, which resists abrasion and wear. Additionally, it offers high impact strength and is the optimal material for chute/hopper liners and machine guards.

Material Properties

UHMW

Yield Strength (tensile)

5,000 psi

Elongation at Break

200%

Hardness

Durometer 70D

Density

0.034 lbs / cu. in.

Maximum Temp

180° F

McMaster Part Number

8752K831

Material Finish

UHMW comes in an opaque black or white color and can be machined to a range of surface finishes. It also has a slippery texture, which is ideal for machine guards and liners.

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 tool 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.

UHMW FAQs

Is UHMW machinable?

Ultra-High-Molecular-Weight Polyethylene (UHMW) is a great material for machining. A hard plastic with a slippery surface, it is resistant to abrasion and wear, and allows for an extended equipment life which helps cut maintenance costs. It provides high-impact strength and is the optimal material for machine guards and chute/hopper liners. UHMW machined parts will outwear all other materials like metals, nylons, or fluoroplastics.

How do you cut UHMW?

CNC Machining is the primary method used to fabricate parts from UHMW. Material made from UHMW can be milled, turned, sawed, drilled, planed, drilled, welded and stamped. Tools should be kept sharp to get the highest quality surface results. UHMW products can also be machined to a high quality finish on the lathe utilizing high speed, light metal working machines.

How flexible is UHMW?

UHMW is flexible enough to perform well in both wet and dry environments. UHMW can be bent sufficiently to accomplish flexibility required for installing parts.

Is UHMW the same as Teflon?

Although UHMW and Teflon (also known as PTFE) are similar, they have some key differences. Teflon is more expensive than UHMW and can only handle about 20% of the load that UHMW can. Both have a low coefficient of friction, but Teflon is more slippery. Overall, UHMW has far better wear properties than Teflon, but Teflon can withstand 4X the temperature that UHMW can during continuous operation.

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