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White Stain or Finger Print Marks

Dear Experts
I have many aluminium (grade 5052 H32) parts that goes through Clear Alodine process. Questions are :

1) What are the solutions to remove white stain or finger print marks that are on the surface after clear Alodine process ?

2) Light scratches (could not be felt by finger nail) on the part surface are detected after Clear Alodine, how to treat this part so that these scratches would not be seen ? Or is there any chemical solution/paste to "hide" these light scratches ?

Thank you.

Lim Chin Tien
Consumer - Singapore
2007

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Fingerprints and stains can only be removed by re-processing. Scratches can perhaps be hidden by lacquering the parts.

Alodine® is quite soft as formed. It hardens somewhat upon air-drying at 60 °C and/or room temperature aging. Parts should be handled gently, by workers wearing clean cotton gloves. This protects both the parts and the workers' health (Alodine® may contain hazardous chemicals).

White stains may be due to contaminated process or rinse tanks, or from inadequate drying (water remaining on parts). The final rinse should be warm DI water (< 50 °C). Check the particular Alodine® process bulletin from Henkel for more information.

Ken Vlach [deceased]
- Goleta, California
Finishing.com honored Ken for his countless carefully researched responses. He passed away May 14, 2015.
Rest in peace, Ken. Thank you for your hard work which the finishing world, and we at finishing.com, continue to benefit from.
2007