Light Resin Transfer Molding (LRTM)

LRTM is a closed-mold composite process. Dry fiberglass reinforcement is loaded into a rigid lower mold, a lighter upper mold is closed over it, and a vacuum draws the resin through the reinforcement until it fills the part. Once the resin cures, the part comes out of the mold with a finished surface.

Standard RTM clamps two heavy matched molds and injects resin under pressure. LRTM uses a lighter upper mold and relies on vacuum, so it runs at lower pressure. That usually means lighter, less costly tooling, which can make LRTM a good fit for mid-size production runs.

LRTM works well for medium to large panels and covers with moderate curves, such as fenders, truck roofs, cowl panels, engine covers and battery boxes. Very deep or highly complex shapes are better reviewed with us first, because the right process depends on the geometry.

When you need a finished surface and a consistent thickness from one part to the next. Hand lay-up is an open-mold process, so only one face comes out finished and the result depends more on the operator. LRTM is a closed process, so it is more repeatable across a run.

Send a drawing or 3D file of the part, the volume you expect to order, and the material or performance requirements. If you have a sample or specific finish needs, include those as well and we will take it from there.