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High Temperature, Low CTE Tooling Material


LAST-A-FOAM® FR-4800 is a high-temperature tooling foam board with low CTE which can be used with high-temperature resin systems, such as vinyl esters, epoxies and BMIs, in high-pressure autoclaves and fiber-reinforced composites.

It can withstand peak temperatures up to 480°F (249°C) and continuous use temperatures up to 400°F (204°C). The FR-4800 tooling board is significantly better than other plastics in the market because it does not warp or twist even at elevated temperatures. It will not change shape throughout the course of thermal cycling, preventing out-of-tolerance parts. Furthermore, its predictable and repeatable CTE makes it easy to calculate a tooling correction factor which helps improve the ability to produce high-tolerance parts. This is especially important in the production of parts for the aerospace, defense and automotive industries.

FR-4800 CTE
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Download FR-4800 Tooling Guide


The FR-4800 low CTE tooling board will machine well with traditional aluminum tools.  Due to its density, the FR-4800 does wear cutting tools much faster than other LAST-A-FOAM® products.  As a result, carbide tooling is required, CVD or PCD tooling is highly recommended.  It is also recommended you do a rough cut first, leaving an extra 1-3 mm for finishing.  Consult our FR-4800 Tooling Guide for additional CNC machining recommendations. Use appropriate personal safety protection in accordance with LAST-A-FOAM® FR-4800 Safety Data Sheet.

Sealant Compounds

The FR-4800 is designed with a hard, smooth finish and does not require the use of a sealant compound.  However, if planning to apply a liquid mold release agent, sealing the tool surface is recommended.

Download FR-4800 Tooling Guide


  • Max use temperatures up to 480°F (249°C)
  • Continuous use temperatures up to 400°F (204°C)
  • Low, predictable and repeatable CTE
  • Recommended cool-down rate (1°F to 2°F per minute)
  • Fully-cured, no outgassing
  • Dimensionally predictable at elevated temperatures
  • Machinable, doesn’t chip out
  • Static-dissipative
  • Offered at 48 pounds per cubic foot
  • Made in USA
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  • Fiber-reinforced composites
  • High temperature resin systems
  • High-pressure autoclave
  • Foam master
  • Prepreg composite layup tools
  • Vacuum forming
  • Short-run tooling
  • Pattern making
  • Monolithic tools and molds
  • Prototype tooling



Products Density (lbs/ft3) Height (in) Width (in) Length (in) Request a Quote
FR-4800 48 4 24 48 Quote »

Products Density (kg/m3) Height (cm) Width (cm) Length (cm) Request a Quote
FR-4800 770 10 61 122 Quote »

Shown are maximum standard stock based on density. Custom sizes are available. Cut sizes are available from 0.125 inches (3.175mm) up to standard stock heights as listed above

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