Metal finishing Q&As since 1989

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Paraffin Based Polishing Compounds

2005

We use a polishing compound 'bar' which they call 'Blue Ice'. I know this is paraffin based. This compound is to only be used for aluminum substrates.

We started having a problem with our antique finish on brass substrate. The black selenium based finish started wiping off of the substrate...not 100%, but in areas.

We discovered that the 'Blue Ice' compound was being used on the brass substrate that is producing the defect. Operator's are putting quite a bit of the compound on their polishing belts that put the 'brushed' finish on the brass parts. We recently changed this part from a manual brushing operation to a robotic brushing operation where the 'Blue Ice' is now applied.

We have aqueous cleaners on our plating lines, which works just fine (for about 30 years now). We were told, the 'Blue Ice' should not be used to brush finish the brass substrates...only used for aluminum. We were told it takes a 'solvent' to remove a paraffin based product.

We would like to hear some responses out there and what others think of this situation.

Thanks,

Gloria Schwedler
Plating and Polishing - Indianapolis, IN, USA

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The government has taken solvent cleaning away from us and there is no water based cleaning compound that will remove burned and embedded paraffin from brass and aluminum.

Robert H Probert
Robert H Probert Technical Services

Garner, North Carolina

2005

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They didn't quite take solvent cleaning away from us, Robert, but they did make it very difficult (not totally without reason, as billions of dollars have been spent on solvent cleanups and many more will have to be spent). But they did, it seems, take away CFCs and other solvents believed to be ozone-destroying, ceding the manufacturing rights to the 3rd world via article 5 of the Montreal protocol (http://www.unep.org/ozone/pdfs/Montreal-Protocol2000.pdf).

Ted Mooney, P.E.
Striving to live Aloha
finishing.com - Pine Beach, New Jersey
2005

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2005

Hi Gloria

Its not impossible to clean off paraffin based compounds with waterbased solutions, but take some steps. We had the problem on our now closed factory in Germany. First step is soak cleaning, second is ultrasonic cleaning, then electrocleaning, and last soak clean and rinse. Not easy but also not impossible.
Best of luck !

Bo Kønig
Food Industry - Odense, Denmark

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I understood that you can't electroclean aluminum. So one of us misunderstood something :-)

Ted Mooney, P.E.
Striving to live Aloha
finishing.com - Pine Beach, New Jersey
2005

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Regarding my initial question: The compound I refer to is supposed to be used when polishing on aluminum only.

The robotic and hand polishers are using the compound on BRASS substrates....not aluminum!

When we plate the brushed brass parts with semi-bright nickel and decorative chrome, we don't seem to have a major problem here (we use typical pretreatment for nickel/chrome - primary cleaner, secondary cleaner, electroclean (lots of rinses in-between and activators prior to nickel and chrome plating).

The problem lies with an antique finish we are putting on the brushed brass parts. The antique finish is not electrolytic....its a dip process. We use a typical pretreatment cleaning process here, and an acid salt prior to antique process. The antique color will not soak into the part....you see brass showing through.

So the issue has nothing to do with aluminum. It has to do with a polishing compound that may be paraffin based. I wanted to know if anyone has experienced this type of problem and what type of aqueous cleaner will remove this type of compound.....or is there a better compound out there that will cool down the polishing belts so we don't have 'chatter'. ** Polishers stopped using the 'Blue Ice' block compound and are using something else....however, now we have chatter and they say we took away their tool to produce a good part.

Gloria J. Schwedler
- Indianapolis, IN, USA
2005

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2005

Most Polishing compounds are stearic acid [on eBay or Amazon] & Parrafin wax with some abrasives. If it's wax is 100% Parrafin I'd be surprised. Anyhow, to clean up you shouldn't need a solvent. Try how water with TEA (triethanolamine) or just plain old dishwashing detergent to emulsify the wax.

Also, some compounds (usually brown) contain Tripoli which is partly SiO2. This interferes with some electroplating processes. This almost certainly isn't the problem but it's worth throwing out there.

Mark Nolde
- Sydney, Australia