The authoritative public forum
  for Metal Finishing since 1989
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Diamond burnishing of chrome plating

My client asks me to diamond burnish my hard chrome plating. I need help regarding burnishing. Can I polish the surface using diamond paste? If yes then kindly mention the procedure. Thanx.

Shashank
- Kanpur, UP, IND
2003

Hard chrome is too thick and has such an irregular surface that diamond paste will only work after a very good grinding and lapping. If the parts are cylindrical this lapping can be done over a lathe with a reciprocating vibratory air apparatus mounted with diamond stones made of bronze with fine diamond particles. Then a clean piece of cloth or felt with oil base fine diamond paste will render a very shiny look. Again, it will all depend on successively finer and uniform steps.

Guillermo Marrufo
Monterrey, NL, Mexico
2003

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If your client asks Diamond Burnishing. Diamond burnishing is a BURNISHING Process and NOT lapping. A special diamond burnishing tool is available from the following manufacturers. More details about construction and working principle is available on their websites / catalogs. Elliott, USA Cogsdill, USA, Mech-India, India

Yashwant Pawar
manufacturer of burnishing tools - Mumbai, Maharashtra, India
2004

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2004

Burnishing is a cold rolling process without removal of metal. A set of rollers is used to roll on the component surface with adequate pressure. As a result all the pre-machined peaks gets compressed into valleys thus giving a mirror like surface finish.

Advantages of Roller Burnishing

1. Mirror like surface finish
Surface finish ranging from 0.05 Ra - 0.2 Ra can be achieved easily by using Bright Burnishing Tools.

2. Dimensional Consistency / Repeatability
Very close and consistent dimensional tolerance can be achieved in several thousand components by using Bright Burnishing Tools. Assembly problems are totally eliminated since part dimensions are maintained within tolerances.

3. Single Pass Operation
Since roller burnishing is single pass operation very less cycle time is required to complete the job to required surface finish and tolerance. Hence better results are achieved with less cycle time unlike grinding, honing and lapping.

4. Increase in Surface Hardness
Since Roller burnishing operation is cold rolling process, work hardening takes place on the cold worked surface. Roller Burnishing gives a better wear resistance on the rubbing surfaces thereby the increases the part service life.

5. Reduces the Reworks and Rejections
In most of the operations (such as reaming and boring) there is a chance of maintaining the dimensions under size or over size especially in mass production.

Srinivasan
- Coimbatore, India

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It is possible to diamond burnish chrome plate, however you must not put too much pressure on the component as it will 'over burnish' and flake.

Search google for diamond burnishing tools.

Lee Donaldson
- Warwickshire, Nuneaton, UK
November 28, 2008