metfinoh

Re: Removing Anodize Coating

Does anyone know the best way to remove an anodized coating and prep the part for a new one. I would very much like to use anything other than nitric acid, due to its availability and toxcicity.  Thanks for your help.

Adrienne

Re: Removing Anodize Coating

[color="DarkSlateBlue"]We have a great product called AN775, that is designed to be used at room temperature, replacing the standard chrome phosphoric strip solution and eleminating chrome treatment problems.  The AN775 will extend your rack life 3 to 4 times.  Also, will eiliminate the contamination of your etch tank.

You can purchase this product and see the product datasheets on our website www.finishingmarket.com

Adrienne Gilbert
finishingmarket.com
(828) 278-2103[/color]

Ira Donovan

Re: Removing Anodize Coating

Adrienne,

A chromic acid and phosphoric acid mixture is probably the best option regarding the rework aspect of the component.  Unfortunately, it is even more toxic than the nitric acid process.

Regards,

Ira Donovan, M.S.F.

Ryan Cook

Re: Removing Anodize Coating

Using a sodium hydroxide type etch is quick and if done properly (with adequate agitation), will leave the part stripped and ready to replate quickly.

The only type of contamination you will witness from a caustic style etching to remove the anodic coating is a spike in the aluminium content, which is common in an etch tank.. 

Take care while stripping to not over etch the parts. or you will cause a "galvanized" appearance.

also keep in mind that after stripping the part in caustic you can expect to have a Matte appearance to the part.  if a shiney, polished look is desireable you may need to polish the part after stripping in the etch.

post how the progress went..  success or otherwise.

metfinoh

Re: Removing Anodize Coating

I should have said in the begining - we are currently using our etch tank for stripping racks.  This causes the etch tank to get worn out much faster and sometimes eats the racks.....  There must be a more controled/safe way to do this.  I am planning to try that AN775 rack strip product from finishingmarket and will let you know how it goes.

Ryan Cook

Re: Removing Anodize Coating

I have an additive that you can put into your etch tank that will create a "never dump" etching solution.  JNR SI Additive when used in conjunction with sodium hydroxide with produce a uniform etching solution, That never needs to be dumped. only added to. The aluminium concentration will reach a certain point that the viscosity of the solution increases to the point that the dragin drag out becomes equal..