The authoritative public forum
  for Metal Finishing since 1989
-----

Problems Bright Dipping Iron

Hello,

I've had some success using the bright-dipping formulation in the ASM Handbook, which is 6% HF and the balance 30% H2O2. I try to control the temperature so that it's between 20-25 deg.C. However, lately I've been getting "stain" spots on less than 10% of the surface of the metal. The colors I've seen were either dull-light-blue or reddish brown. I'm assuming these stains are an oxide residue on the surface. How can these stains be avoided?

I've noticed that the power of the bright dipping solution tends to dissipate after use. What's the best way to rejuvenate the solution? Should I just do-away with the entire solution?

Finally, are there any alternatives to using the HF/H2O2 solution? I haven't found any, but maybe somebody can point me in the right direction.

Best Regards,

Luke Autry

Luke Autry
Graduate Student - Glastonbury, Connecticut
December 6, 2010