Diamond Cutting Process

Diamond cut alloys have become increasingly popular over the last decade, with most manufacturers now offering diamond cut alloys across their entire vehicle range.

Diamond Cut or ‘Diamond Turned’ alloys can be identified by their polished, 'CD-like' finish, normally combined with a painted inner surface.

The Diamond Cut finish is achieved by first applying the desired colour to a wheel before using a diamond tipped lathe to remove an extremely thin layer from the wheel face. You may also hear the technique being referred to as ‘diamond polishing’, or ‘diamond turning’.

Pro Alloys Wales are proud to be the ONLY mobile wheel restoration company in South West Wales operating diamond cutting lathes.

Used by the worlds leading wheel manufacturers, diamond cutting lathes are quite simply the best on the market! Providing an extremely accurate diamond cut profile, removing the smallest possible amount of material from the wheel surface.


Before any work commences, a thorough inspection is carried out to assess the condition of the wheel. As the machined surface is only protected by a layer of lacquer, any small chips or scuffs can result in water penetrating beneath the lacquer, causing a ‘spidering’ or ‘milking’ effect. Diamond cutting involves removing a thin layer from the wheels face, so we need to ensure that the wheel has not been too heavily machined in the past, removing too much material from the wheel. Any extensively deep damage may mean that the wheel is too heavily damaged to be ‘re-cut’.

Preparation and Paint

With pre-inspection complete, we de-bead the tyre, begin filling any deep scratches and sand to a smooth finish. Once this has been completed, the next step is to prime the wheel and add a base colour. This process is swift up thanks to our powerful infra-red lamps. After colour has been applied to the wheel, the diamond cutting procedure begins…


Once prepped and painted, each wheels profile is mapped and programmed for machining using the markets latest computer-aided-manufacturing software. The program is developed to generate the tool paths that will precisely re-machine the wheel face, whilst retaining the original wheel profile. 

CNC Diamond Cutting

This is where the real action happens and our lathe comes into it's own. Our lathe will remove as little as 0.01” per pass to achieve the highest level of precision. The final pass on our lathes will typically remove as little as 0.008” at a spindle speed and tool feed-rate that will give the ultimate Diamond Cut Finish, without the heavy radial lines found from inferior equipment.


With the diamond cutting process complete, each wheel will undergo a deburring process before it is ready for coating. An anti-corrosive barrier is applied directly to the metal to prolong the wheels life and prevent corrosion.

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