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Make-up & Operating temperature of Electropolishing solution?

May 25, 2011

I am opening a metal finishing shop in El Cajon Ca. I built the place from the ground up and now I am putting the solutions together. My Electropolishing tank is 120 gal. I have made it up to the following parameters: 66% Phosphoric acid & 34% sulfuric acid. First Question....... Is this a good formula? Second question, what will be my optimum operating temperature?
RSVP ASAP as I am eager to test my formulation!

Scott Wayne
Operator - El Cajon, California, U.S.A.

I hope that you have a good exhaust system with a fume scrubber for your system. Also, how is your tank made and heated. The solution is hard on tanks and heaters.

James Watts
- Navarre, Florida
First of three simultaneous responses -- May 27, 2011

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Second of three simultaneous responses -- May 27, 2011

By volume: 25% sulfuric + 75% Phosphoric (85% grade) is a better solution, although yours will work.

Optimum operating temperature 90-120° F.

You will need rectification and bussing adequate to provide 1 amp/sq in.

Run hard, you will need cooling and ventilation.

You'll also need good cleaning, rinsing and wastewater treatment.

You'll need appropriate permits, state and local.

Jeffrey Holmes, CEF
Spartanburg, South Carolina

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In your situation, you'd be much better off using a proprietary formulation from a company with a strong background in electropolishing. Hubbard Hall comes to mind, but there are others. That way you get all of their knowledge and support. You'll need it to get up and going. Later down the road you can play with your own formulation if you choose to, but you may decide, as many have, that it is worth it to pay a little extra for the chemistry.

Jon Barrows, MSF, EHSSC
GOAD Company

Independence, Missouri

Third of three simultaneous responses -- May 27, 2011