SURFACE FINISHING / BEAD BLASTING

Bead Blasting Service: Smooth Satin Finishes Without Material Removal

Glass bead blasting produces uniform matte and satin finishes on aluminum, stainless steel, and titanium parts. No material removal, compressive surface stress, and perfect pairing with anodizing. ISO 9001 certified quality at FIRMFG.

Bead Blasting Service: Smooth Satin Finishes Without Material Removal

Bead blasting is a surface finishing process that propels fine glass beads at a part using compressed air. Unlike sand or grit blasting, the spherical glass beads peen rather than cut the surface, producing a uniform matte or satin finish with no material removal. The result is a smooth, non-reflective surface that conceals machining marks while preserving dimensional accuracy.

At FIRMFG, our bead blasting service achieves surface roughness from Ra 0.4 to 3.2 μm using glass beads ranging from 40 to 400 mesh. The process is ideal for aluminum, stainless steel, and titanium parts — particularly consumer electronics housings, medical devices, and decorative hardware where a premium satin appearance is desired. Bead blasting also imparts beneficial compressive residual stress that improves fatigue resistance.

Bead blasting is frequently combined with anodizing or electroplating for enhanced appearance and corrosion protection. The bead-blasted texture produces a softer, more refined finish under anodizing compared to raw machined surfaces. Request a quote for standalone or combined finishing pricing.

The Bead Blasting Process

From bead selection through post-processing inspection, each step ensures a uniform, repeatable satin finish across every part in the batch.

Setup: 10 minutes

Step 1: Glass Bead Size Selection

The glass bead size is selected based on the desired surface roughness and part geometry. Fine beads (200–400 mesh) produce a smooth satin finish (Ra 0.4–0.8 μm), while coarser beads (40–120 mesh) create a more textured matte surface (Ra 1.6–3.2 μm). Bead size directly determines the final texture uniformity.

Typical use: Fine (200–400 mesh) for cosmetic; coarse (40–120 mesh) for textured

10 – 30 minutes per batch

Step 2: Surface Preparation & Masking

Parts are cleaned to remove oils and contaminants. Critical surfaces such as threads, bearing seats, and sealing surfaces are masked with tape or custom fixtures to protect them from bead impact. Masking ensures only the intended surfaces receive the textured finish.

Typical use: Tape masking, custom fixtures, silicone plugs for holes

5 – 20 minutes per batch

Step 3: Bead Blasting

Glass beads are propelled at the part surface using compressed air at 1–4 bar pressure. The spherical beads peen the surface, creating a uniform pattern of microscopic indentations that scatter light evenly. Unlike sand or grit blasting, glass beads do not cut or remove material — they deform and smooth the surface.

Typical use: Pressure blasting cabinet, 1–4 bar, 60–90° nozzle angle

10 – 20 minutes per batch

Step 4: Post-Processing & Inspection

Beads and dust are removed by air blow-off and ultrasonic cleaning. Parts are inspected for surface uniformity, roughness measurement (Ra), and masking integrity. Bead blasting is frequently combined with anodizing or electroplating for enhanced appearance and corrosion resistance.

Typical use: Air blow-off, ultrasonic clean, roughness gauge inspection

Bead Blasting Specifications

Key process parameters and capabilities of our glass bead blasting service.

SpecificationValue
Surface Roughness (Ra)0.4 – 3.2 μm
Glass Bead Size40 – 400 mesh (38 – 425 μm)
Blasting Pressure1 – 4 bar (15 – 60 psi)
Material RemovalNone (peening only)
Surface EffectUniform matte / satin finish
Quality StandardISO 9001:2015 Certified

Bead Blasting vs Sand Blasting

Understanding the difference between bead blasting and sand blasting helps you choose the right process for your application and material requirements.

CriteriaBead BlastingSand Blasting
Material RemovalNone (peening only)Yes (cutting and erosion)
Surface Roughness (Ra)0.4 – 3.2 μm1.6 – 12.5 μm
Surface StressCompressive (beneficial)Tensile (can cause cracking)
Surface AppearanceSmooth satin / matteRough matte
Dimensional ChangeNegligible0.05 – 0.5 mm removal
Suitability for Thin WallsExcellentPoor (can warp or pierce)
Best ForCosmetic, precision partsHeavy rust/scale removal

Bead blasting is the preferred choice for cosmetic and precision parts, while sand blasting is better suited for heavy rust and scale removal on structural components.

Material Compatibility

Bead blasting works on most metals, but bead size and pressure must be tailored to each material's hardness and sensitivity.

MaterialBead SizePressureNotes
Aluminum80 – 200 mesh1 – 2 barBest results; produces uniform satin. Pairs perfectly with anodizing for consumer electronics.
Stainless Steel60 – 150 mesh2 – 3 barCreates consistent matte finish. Higher pressure needed due to material hardness.
Titanium100 – 200 mesh1.5 – 3 barExcellent for medical and aerospace. Smooth, biocompatible surface for implants.
Copper / Brass120 – 200 mesh1 – 1.5 barLow pressure prevents surface deformation. Produces soft satin sheen on decorative parts.
Carbon Steel60 – 120 mesh2 – 4 barRequires immediate oiling or coating to prevent flash rusting after blasting.
Zinc / Die Cast150 – 300 mesh0.5 – 1.5 barVery low pressure to avoid surface damage on soft zinc alloys.

Finish Options

Three primary finish types cover the range of aesthetic and functional requirements for bead-blasted parts.

Matte Finish

A non-reflective, flat surface produced by coarser glass beads (40–120 mesh). Light is scattered uniformly in all directions, eliminating glare and hot spots. Ideal for industrial and functional parts where reflection is undesirable.

Ra 1.6 – 3.2 μm

Satin Finish

A smooth, low-sheen surface produced by medium glass beads (120–200 mesh). Provides a refined, premium appearance with subtle light reflection. The most popular finish for consumer electronics and decorative hardware.

Ra 0.8 – 1.6 μm

Uniform Texture

A consistent, repeatable surface texture produced by fine glass beads (200–400 mesh). Ensures batch-to-batch visual consistency for production parts. Often specified for products requiring a controlled tactile feel.

Ra 0.4 – 0.8 μm

Design Guidelines for Bead Blasting

Follow these DFM rules to ensure consistent finish quality, protect critical surfaces, and optimize cost for bead-blasted parts.

FeatureRecommendedMinimum
Minimum Wall Thickness0.8 mm (0.031")0.5 mm (0.020")
Masking Clearance3 mm from masked feature1.5 mm
Internal Hole BlastingDiameter ≥ 5 mm, depth ≤ 3× diameterDiameter ≥ 3 mm
Thread ProtectionMask all threaded holesMask critical threads
Surface Roughness ToleranceRa ± 0.2 μmRa ± 0.5 μm
Edge RoundingEdges will soften slightlySpecify critical edges to mask
Pre-Finish SurfaceRa 1.6 μm or better before blastingRa 3.2 μm
Combination with AnodizingBead blast before anodizingSpecify blast-first sequence

DFM Tips for Bead Blasting

  • Mask all threaded holes and critical mating surfaces with tape or plugs to prevent texture transfer that could affect assembly.
  • Maintain a minimum wall thickness of 0.8 mm. Although bead blasting does not remove material, very thin walls can flex under bead impact.
  • Design internal holes with a diameter of at least 5 mm and depth-to-diameter ratio under 3:1 to ensure bead access for uniform texturing.
  • When combining bead blasting with anodizing, specify the blast-first sequence on drawings to ensure proper process ordering.
  • Specify the target Ra value on cosmetic surfaces to ensure batch-to-batch consistency in surface texture.
  • Achieve Ra 1.6 μm or better on the machined surface before blasting — the blasting process refines but does not eliminate deep tool marks.

Bead Blasting Cost Factors

Bead blasting is priced by surface area with adders for masking. Combining with anodizing or electroplating provides package savings.

Pricing Basis

By surface area

Typically $0.50 – $3.00 per dm² depending on complexity

Masking Adder

$2 – $10 per part

Custom masking for threads, holes, and critical surfaces

Combined with Anodizing

Package discount

Bead blast + Type II anodizing: $3 – $8 per dm² total

Combined with Electroplating

Package discount

Bead blast + nickel/chrome plating: $5 – $15 per dm² total

Bead Blasting FAQ

Answers to the most common questions about glass bead blasting at FIRMFG.

QHow is surface roughness controlled in bead blasting?

Surface roughness is controlled primarily by glass bead size and blasting pressure. Fine beads (200–400 mesh) at low pressure (1 bar) produce Ra 0.4–0.8 μm, while coarser beads (40–120 mesh) at higher pressure (3–4 bar) produce Ra 1.6–3.2 μm. We verify every batch with a surface roughness gauge and maintain Ra tolerance of ±0.2 μm on cosmetic surfaces.

QDoes bead blasting remove material from the part?

No. Unlike sand blasting or grit blasting, glass bead blasting is a peening process — the spherical glass beads deform the surface rather than cutting it. Material removal is negligible (typically less than 1 μm), meaning dimensional accuracy is preserved. This makes bead blasting ideal for precision parts and thin-walled components where dimensional integrity is critical.

QCan bead blasting be used on thin-walled parts?

Yes. Bead blasting is ideal for thin walls because it does not remove material or generate heat that could cause warping. We recommend a minimum wall thickness of 0.8 mm for standard blasting, though walls as thin as 0.5 mm can be processed at reduced pressure (0.5–1 bar). For extremely thin walls, we use fine beads and low pressure to prevent any surface deformation.

QCan bead blasting be combined with anodizing?

Yes, and this is one of the most popular finishing combinations. Bead blasting is applied first to create a uniform satin texture, followed by Type II or Type III anodizing for color and corrosion resistance. The bead-blasted surface produces a softer, more refined anodized appearance compared to raw aluminum. We offer this as a package with discounted pricing. Specify the blast-first sequence on your drawings.

QWhat is the minimum batch size for bead blasting?

The minimum batch size is 1 piece for prototyping and 5 pieces for production. Bead blasting is efficient for both small and large batches because the blasting cabinet processes parts quickly (5–20 minutes per batch). Cost per part decreases significantly above 50 pieces. There is no maximum batch size — we process orders from single prototypes to thousands of production parts.

QWhat is the typical lead time for bead blasting?

Standard lead time is 3–5 business days for bead blasting as a standalone process. When combined with anodizing or electroplating, the total lead time is 5–7 days since blasting is done first. Rush service is available for 24–48 hour turnaround on small batches. Bead blasting is one of the fastest surface finishing processes, with the actual blasting taking only 5–20 minutes per batch.

Bead Blasting Applications

FIRMFG provides bead blasting for industries where a uniform, premium satin finish adds value to the final product.

Consumer Electronics

Aluminum housings, laptop chassis, smartphone frames with satin finish

Medical Devices

Titanium implants and surgical instruments with biocompatible texture

Aerospace

Structural components, panels, and fittings requiring uniform finish

Decorative Hardware

Door handles, fixtures, and architectural elements with satin sheen

Automotive

Engine covers, trim pieces, and custom motorcycle components

Mold Tooling

Mold cavity texturing and surface preparation before polishing

Start Your Bead Blasting Project

Upload your CAD files and get a free bead blasting quote within 24 hours. Our engineers provide finish recommendations, masking guidance, and package pricing for combined anodizing or electroplating. ISO 9001 certified quality with 3–5 day turnaround.