Vibratory finishing of alloy wheels: process and result

An aluminium alloy wheel is one of the most frequent parts brought in for finishing. And one of the parts where the working medium is most easily got wrong.

What vibratory finishing gives you

A uniform surface. Machining marks disappear, and the appearance becomes uniform across the whole part, including the spokes and hard-to-reach areas.

Rounded edges. Every edge is processed the same way — an advantage manual work does not give.

Preparation for coating. A uniform surface means a uniform layer of paint or lacquer.

Why steel abrasive is not used

The wheel is aluminium alloy. The basic rule says the medium is chosen according to the hardness of the part.

A ceramic medium or a steel abrasive sized for cast iron hits aluminium instead of finishing it. Plastic media are used, suited to materials of lower hardness.

Blasting or vibratory finishing

The two do different things to the same part.

Blasting removes old paint, oxides and deposits. It is the cleaning operation, used in refurbishment.

Vibratory finishing works the surface: it evens it out, rounds edges, prepares it for coating.

A complete refurbishment flow uses both: blasting to get to clean metal, vibratory finishing to obtain the final surface.

What matters in the setup

Media shape — it has to reach between the spokes and not lodge in the bolt holes.

Separation — the wheel is much larger than the media, so screen separation works directly.

Load ratio — wheels are large parts; few fit in a bowl, and the ratio is calculated by volume, not by piece count.

Corrosion protection — aluminium does not rust, but a freshly finished surface can stain if it stays wet. A compound with a protective effect solves that.

Related reading

• Sandblasting Car Wheels — What Abrasive to Use and How the Process Works
• What is vibratory finishing and what benefits does it bring?
• How to choose vibratory finishing media