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Manufacturing services · Chapter B · Method 08

Polyurethane casting

Core TCI route

Two-part polyurethane is mixed and cast into silicone or rigid tools. Covers rigid, flexible and elastomeric parts without the cost of steel tooling.

Meter-mix-dispense machine for two-part polyurethane.
Meter-mix-dispense machine for two-part polyurethane. Representative process photo · Scheugenpflug AG · CC BY-SA 3.0 · Wikimedia Commons

How it works

Polyurethane casting, step by step.

A labelled schematic of the process (not to scale), and the four steps every job goes through.

Labelled diagram showing how polyurethane casting works
Schematic · not to scale. Drawn by TCI Group.
STEP 01

Tool

Cast a silicone tool from the master, or use a rigid mould.

STEP 02

Meter & mix

Mix A and B by hand or with a meter-mix machine.

STEP 03

Cast

Pour or inject into the tool, under vacuum if needed.

STEP 04

Cure

Cure, demould and post-cure for full properties.

Reference figures

What to expect.

Typical industry values to help you plan. We agree the figures for your part on the drawing.

Tolerance±0.25 mm or ±0.003 mm/mmWhichever is larger
Shrink~0.15 %Typical
HardnessShore A 20 – Shore D 85Elastomer to rigid
Min Wall0.5–1 mmBy part size
MaterialsRigid, flexible and elastomeric PU; clear, flame-retardant and high-temperature grades.
FinishesSatin or matte as standard; polished or custom finishes agreed at order. Pigmented or painted.
Design guidance
  • Add 3–5° draft where you can.
  • Blunt knife edges with a fillet or chamfer.
  • Keep walls even; very thick sections can deflect on cure.
Best suited toRollers, wheels, bumpers, buffers, industrial tooling and low-volume end-use parts.
Watch-outsSharp corners and fine text may round slightly; moisture affects cure.

More in chapter B

Other methods in Plastics & polyurethane

Next step

Not sure this is the right route?

Send a sketch, photo, sample or CAD file with your quantity and target date. We will recommend the most sensible route and explain the trade-offs before quoting.

Reference figures are typical published industry values for planning, not a guarantee; final tolerances, materials and finishes are agreed in writing for each project.