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Texture Finishing

Mechanical finishing · Mechanical

Texture finishing creates a controlled pattern on the mold so every molded part replicates it.

Injection moldingPremium cost $$$Unchanged
Quote a part with Mold textureCompare mechanical finishing
Texture Finishing on a machined part

What is Mold texture?

Classes include SPI or PIA A-1 through D-3, VDI 3400 textures, proprietary Mold-Tech patterns, and laser-textured geometric or stochastic patterns.

How it works

The tool surface is polished, stoned, dry-blasted, chemically etched, or laser ablated. Molded polymer copies the negative texture, subject to resin, draft, pressure, and shrinkage. SPI or PIA A-1 through D-3 communicates polish and blast method; VDI 3400 communicates increasing texture levels. Practical molded textures span roughly Ra 0.2–18 µm (8–710 µin), but VDI or Mold-Tech code and an approved plaque control appearance.

Why specify it

  • Hides sink marks and light wear
  • Creates grip and anti-glare appearance
  • Replicates texture on every molding cycle
  • Laser texturing enables repeatable local patterns

Where it falls short

  • Texture increases required draft
  • Weld lines and flow can remain visible
  • Repair matching is difficult
  • Low-gloss texture can trap soil

Mold texture at a glance

Mold texture is strongest on cosmetic quality (85 of 100), at a premium cost. It adds little corrosion protection or lubricity. Surface hardness is not rated: the finish leaves the part's own surface.

Corrosion protectionMinimal0 / 100
Surface hardnessNot rated—
Cosmetic qualityExcellent85 / 100
LubricityMinimal10 / 100
Relative costPremium60 / 100
CorrosionHardnessCosmeticLubricityEconomy

Each score is 0–100 against every finish in this catalog. Corrosion comes from salt-spray life (ASTM B117, log scale) and hardness from the finish layer's Vickers or pencil hardness; cosmetic, lubricity and cost are FabDigit's engineering assessment. Economy on the radar is the inverse of cost.

Mold texture key numbers

Typical values from the governing specifications and shop practice; bars are this finish against the highest value among mechanical finishing finishes.

Thickness0 µm0 mil
Thickness
Mold texture is replicated, not coated; practical molded Ra spans roughly 0.2–18 µm (8–710 µin) by class.
Electrical
Unchanged
Appearance
Specified gloss, grain, stipple, geometric, or natural pattern replicated from the tool.

Specifications for Mold texture

The documents a drawing cites to define this finish, with the Type / Class rows that apply. Each links to a page explaining the standard.

Drawing call-out

MOLD EXTERIOR SURFACES VDI 3400 27 TEXTURE; 1.5° MINIMUM DRAFT PER SIDE; MATCH APPROVED COLOR AND TEXTURE PLAQUE; KEEP SHUTOFFS SPI A-2

Which materials take Mold texture?

Verdict per material family, with the grades that behave differently. Each family links to its datasheets in the material library.

Material familyVerdictNotes
Polymer
YesThermoplastics replicate mold texture; gloss and fidelity depend on resin and process.
  • Filled resins can reduce fine-detail fidelity
Polyurethane
YesCast urethane can replicate a textured master or mold.
Silicone
YesSilicone can replicate fine mold texture but perceived gloss differs.
Aluminum
LimitedMetal textures are EDM, laser, or photo-etched on the tool, not a moulded-part texture process.
Stainless Steel
LimitedStainless tools can be textured; moulded stainless parts are not this process.
Steel
LimitedTool-steel cavities are textured; the steel part itself is not VDI-moulded.
Zinc Alloy
LimitedDie-cast zinc can copy cavity texture; draft and fill still control appearance.
Brass
NoNot a moulded-polymer texture process.
Copper Alloy
NoNot a moulded-polymer texture process.
Magnesium Alloy
NoNot a moulded-polymer texture process.
Titanium
NoNot a moulded-polymer texture process.

How Mold texture is applied, and what it does to the part

  1. 1Approve texture plaque and code
  2. 2Polish tool to required base
  3. 3Mask non-textured zones
  4. 4Etch blast or laser texture
  5. 5Mold trials and approve appearance
DimensionsTexture depth changes cavity geometry and can impede release; compensate dimensions and add draft according to texture depth and resin.
Build-up per side0 µm — No post-mold buildup; texture is formed in the mold cavity and affects local molded dimensions.
MaskingUsually needed. Texture only designated mold regions; keep shutoffs, seal-offs, lettering, and precision interfaces protected.
ElectricalUnchanged
AppearanceSpecified gloss, grain, stipple, geometric, or natural pattern replicated from the tool.
Added lead time5–15 working days on top of the bare part

Design rules for Mold texture

What to decide on the drawing before the part goes to the finisher.

  1. State VDI Mold-Tech or SPI/PIA class.The word matte is not reproducible.
  2. Approve a molded plaque.Resin and color change perceived texture.
  3. Increase draft for deeper texture.Texture mechanically resists ejection.
  4. Keep texture off shutoffs.It can create flash and wear.

Mold texture versus the alternatives

Finishes engineers weigh against Mold texture, and when each wins.

FinishCorrosionHardnessCosmeticCostThicknessChoose it when
Mold texture
this page
0—85$$$0 µm—
Brushed Finish
Mold texture vs Brushed Finish →
5—75$$0 µmwhen directional grain is applied to metal after fabrication
Bead Blasting
Mold texture vs Bead Blasting →
5—65$0 µmwhen a non-directional texture is applied directly to a finished metal part
CorrosionHardnessCosmeticLubricityEconomy
Mold textureBrushed Finish

The radar overlays Mold texture with Brushed Finish, its most common alternative — chosen when directional grain is applied to metal after fabrication. Scores in the table are 0–100 across every finish in the catalog.

Cost, lead time and compliance

Relative cost

Texture Finishing is a premium-cost finish ($$$): more expensive than about 70 % of the finishes FabDigit quotes.

Finishing is priced per part with a lot minimum, from FabDigit's own China-side rates. The exact figure appears on the instant quote once the part is uploaded.

Lead time and compliance

Added lead time5–15 working days
RoHSCompliant
NotesLaser texture avoids chemical etchant; chemical tool etching requires controlled bath and waste treatment.

What Mold texture is used for

  • Tool grips
  • Automotive interior trim
  • Electronic bezels
  • Appliance housings

Mold texture — frequently asked

what is VDI 3400 texture

VDI 3400 is a widely used mold-surface texture scale with increasing texture number and roughness. State the VDI level and approve a molded plaque because resin and process alter appearance.

what are SPI mold finish grades

SPI or PIA grades run from A-1 diamond-buffed mirror through B stone, C paper, and D dry-blast classes to D-3. They describe tool-finishing method and resulting appearance.

Mold-Tech vs VDI 3400

VDI 3400 is a numbered texture scale, while Mold-Tech includes proprietary pattern codes. Do not substitute one from an approximate conversion chart without an approved sample.

how much draft is needed for mold texture

Deeper texture needs more draft than a polished wall. A common starting callout may use 1.5° per side for a moderate VDI texture, but the toolmaker and resin supplier must confirm it.

what is laser mold texturing

A laser ablates controlled microgeometry directly into the tool. It can produce local gradients, geometric patterns, and repeatable stochastic grains that are difficult to chemical-etch.