Vibration finish — widely called Scotch-Brite or SB after the abrasive brand that made it popular — is a non-directional satin finish. Instead of long parallel lines, the surface carries a random, finely broken texture.
Why non-directional matters
Every directional finish (No.4, HL) reflects light preferentially along its grain. That is what makes fingerprints, wiping marks and minor scratches visible: they disturb the grain and the eye reads the disturbance. A non-directional surface has no dominant reflection axis, so the same mark largely disappears into the texture.
This is why SB is specified for surfaces that get touched: lift interiors, handrails, door push plates, public-realm cladding, and anything in a food or medical environment that is wiped repeatedly.
How it is produced
The finish comes from an abrasive flap or brush head that is oscillated — moved laterally or rotationally relative to the strip travel — so that no single direction dominates. The variables that define the result are:
- Abrasive grade and type (the "Scotch-Brite" style web, or a flap brush of equivalent cut)
- Oscillation amplitude and frequency
- Contact pressure
- Number of passes and heads
The same platform can often produce both No.4 and SB: the difference is the head, the abrasive and the motion — not the whole machine. If you are buying new and expect to run both, say so at the specification stage, because the head mounting and drive arrangement are easier to design in than to retrofit.
SB compared with No.4
- Fingerprints: SB is clearly better.
- Cost: Abrasive consumption is usually higher on SB.
- Repairability: Both are difficult to repair locally; SB marginally more forgiving.
- Appearance: SB reads softer and slightly less reflective. Some designers prefer the crisper look of No.4.
Process sequence
Preparation (grinding if the incoming surface needs it) → oscillation satin head, often two or three in series → cleaning → drying → protective film. As with all brushed finishes, cleaning is not optional: trapped abrasive fines will stain the surface in storage.