Masking a part?

[00_buckshot]

I have an aluminum part that has a broken steel pin positioned about 1/16" of an inch below the surface of the part I want to anodize. It has proven impossible to drill out with my equipment. Can I just plug this hole with Caswell's masking agent or does the steel have to be completely removed? Keep in mind we are only talking about 1/4" max in total area of the broken steel pin. Is this that much to worry about?

If I was to attempt to anodize it with the pin exposed what could/would happen?

Thanks for the help.

[NeoMoses]

I believe that anodizing it with the steel exposed will dissolve the steel into your acid bath. I've heard (although I've never done it myself) that this is a method sometimes used to remove otherwise impossible to remove broken bolts. I'm not sure if the amount of steel dissolved would affect your anodizing results or not, though.

I believe masking it would work if you want to keep it from reacting with your acid during andozing.

[lastone75]

what i have done in the past is i have a speprete anotank setup. and use the to desolve taps that have broken in parts i have made. only draw back is you would need to strip and polish it after this is done. but it will only need to stay in the stripper more then a minute or 2 since it's not sealed anno. this has saved my ass a few times. good luck. i don;t recommond using it in the same tank as you would normaly annodize in.


my setup for ths uses a 2 gallon bucket. and about 1/4 of a gal of sulfuric and about a galon and a half of destiled water. i use a cathode thats is rufly 5x7. your not trying to ano just trying to desolve the metal.
and run it at a constent 12volts.

when you do this you will see bubbles coming from where the metal is that means the metal is being actacked. you should check it about every 5 minutes to see how it is going.

[00_buckshot]

I've been talking with a professional anodizer online and he said what they do is dunk the part in nitric acid. This will dissolve the pin according to him and do no harm to the aluminum.