High Density Urethane (HDU) Boards

About High Density Urethane (HDU) Boards

High density urethane (HDU) board is a rigid, closed-cell polyurethane material used for CNC machining, hand carving, prototypes, and tooling. It machines cleanly, resists cracking, and can be bonded into larger shapes for final shaping or machining.

Materials are offered from multiple product lines, including RAKU® TOOL Styling Board, Precision Board Plus™, and Last-A-Foam®. Available in a wide range of sheet sizes, thicknesses, densities, and temperature capabilities, HDU boards support applications in aerospace, industrial manufacturing, signage, and modeling.

Length, width, thickness, and diameter tolerances vary by size, by manufacturer, brand, and grade.

High Density Urethane Board Options

RAKU® TOOL SB-0160 (light gray, 10lbs/ft3) – is designed for styling and design models, data control models, and supporting structures for close contour paste. It has a smooth surface with low dust, is lightweight, easy to shape, and is resistant to organic solvents.

RAKU® TOOL SB-0240 (light green, 15lbs/ft3) – is a polyurethane board for styling models, epoxy laminating molds, support structures, and negative molds for casting. It has a very good surface structure, is easy to machine, resistant to organic solvents, and has good temperature resistance.

RAKU® TOOL SB-0320 (apricot, 20lbs/ft3) – is designed for styling, design, and data control models. It has a very good surface structure and can easily be shaped and machined.

RAKU® TOOL SB-0470 (apricot, 29lbs/ft3) – is a polyurethane board for styling and master models. It has a very good surface structure and is easy to machine.

Precision Board Plus™ PBLT-15 (low temperature, 15lbs/ft3) – Closed-cell, rigid high density urethane board formulated for durability and fine detail. Commonly used for prototype machining, pattern making, composite layup tooling, vacuum form tooling, master models, and indoor or outdoor signage.

LAST-A-FOAM® FR-3700 Performance Core Series (3–25 lbs/ft³) – Closed-cell, flame-retardant polyurethane foam offering high strength-to-weight ratio, low water absorption, and clean machinability. Used in aerospace interiors, structural components, tooling, and industrial applications requiring lightweight performance and flame resistance.

LAST-A-FOAM® FR-4500 Tooling Board Series (20–50 lbs/ft³) – Rigid, high-temperature polyurethane tooling boards designed for composite layup tooling, master models, and pattern making. Provides excellent dimensional stability, good surface finish, and resistance to moisture and solvents.

LAST-A-FOAM® FR-4700 High-Temperature Tooling Board Series (30–50 lbs/ft³) – High-performance polyurethane tooling boards with elevated temperature resistance, used for high-temp composite layup tooling, autoclave tooling, and other demanding aerospace and industrial applications.

LAST-A-FOAM® FR-3800 FST Performance Core Series (3–40 lbs/ft³) – Fire, smoke, and toxicity-compliant polyurethane foam core meeting stringent aerospace requirements, used for aircraft interior panels, bulkheads, and other safety-critical applications.