The authoritative public forum
  for Metal Finishing since 1989
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Aluminium Piston Finishing

2002

I am in the process of making aluminium pistons for generators. The piston dia is about 350 mm and the problem I am facing is that I am not able to get the desired finish of my product. Presently I am doing the finishing with a carbide tip. The piston is in the cylindrical form.

The composition of the material is as follow:

Al. : 82.68%
Si. : 13.20%
Fe. : .736%
Ni. : 1.03%
Mn. : .035%
Zn. : .390%
Cu. : 1.26%
there is also Pb., Ti., Cr. also but in very less quantity.

Please advice what to do to increase the finish of the piston. Note: No plating can be done as the sizes that are made are maintained in microns.

Thank you,

Hritik Gupta
- Delhi, India

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It sounds like you have a rather large part; therefore, I'd probably recommend using a cotton buff type process with an alum rouge. If you have a lot of volume, it can also be done in a tub type mass finishing vibratory machine with a treated dry organic media process; however, the length of your part may cause problems.

AF Kenton
retired business owner - Hatboro, Pennsylvania
2002

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Dear piston manufacturer, finish of piston can be improved by proper heat-treatment and with good quality of cutting tool.

Thanks.

JS Sambhi
- Ghaziabad,UP, India
2003

Diamond tool should be used for fine machining for final diameter. You may use carbide tip tool and keep 0.010 fillers for Diamond tool margin

Praksh Sarvaiya
pistons - Rajkot, Gujarat, India
December 16, 2009