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  for Metal Finishing since 1989
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Electropolishing tank construction

Can I use a stainless steel (316L) tank for electro polishing without being lead lined . I would have small volumes of components 316L for processing.

Chris Spelman
- Shannon, Co.Clare, Ireland
2003

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First of two simultaneous responses --

I wouldn't recommend it, the tank will start to corrode when the electrolyte is left standing. It may take some time, but dumping the electrolyte over the floor is not a good idea.

Trevor Crichton
R&D practical scientist
Chesham, Bucks, UK
2003

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Second of two simultaneous responses --

Yes

Jon Quirt
- Minneapolis, Minnesota
2003

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My good buddy 5 blocks from my house has operated a 316l e.p. tank for 11 years and has had no problems with leakage. It holds 500 gallons of your typical sulfuric/phosphoric acid electrolyte,(and a few additives). If your 316l tank is corroding then a buffer can be used, or a weaker electrolyte. Boric acid can be used as a buffer, which helps "regulate" the rate at which your bath can etch parts under current load and standing. You can also extend bath life expectancy by buffering. Generally, your electrolyte alone should not be strong enough to etch 316 l easily. Of course, surface roughness will play a very important role in how well any metal resists corrosion.

Good luck!

Jeff Swayze
- Kwlowna, B.C., Canada
2003