ForMatter/Finishes/mold_finish/SPI B1 (fine paper polish, 600-grit)
finish_mold_spi_b1

SPI B1 (fine paper polish, 600-grit)

mold_finish · polished · SPI B-1, semi-gloss mold finish

A fine, semi-gloss mold finish from 600-grit emery paper polishing. The molded part reads slightly soft-glossy — not optical, not matte. The everyday consumer-electronics housing finish, kitchen-tool grip, cosmetic case interior.

SPI / SPE finish B1 — 600-grit emery paper polish on tool-steel cavity. Surface roughness Ra ~0.1–0.2 µm. B2 is 400-grit (Ra ~0.3); B3 is 320-grit (Ra ~0.4). All B-series are semi-gloss to fine-matte; molded parts come out with a soft sheen that hides minor surface defects. Cheaper than A-series (no diamond compound, no felt-buff stage); the practical 'looks like a finished injected part' default for non-optical work.

character — soft glossy, fingerprint-tolerant, the consumer-product default.

Finish properties

  • levelpolished
  • subcategorySPI / SPE paper polish
  • Ra (µm)0.15
  • applies topolymer
Produced by processesInjection Molding

Second life

reversibilityzero on the molded part — the mold-cavity surface is transferred at the moment of forming and cannot be undone without re-molding from a different cavity.
blocks substrate recyclingno
renewabilityzero on the existing part; the mold cavity itself can be re-polished or re-textured by the toolmaker for subsequent runs.

SPI / SPE Mold Surface Finish standards (A-1 through D-3); VDI 3400 mold-cavity texture reference plates.

Citations

  • standard · SPI/SPE Mold Finish Standards (Society of the Plastics Industry, AB-3) — B1 / B2 / B3 paper-polish reference.