Anodizing Multiple Pieces

[acidrain]

I'm still leaning towards different alloys... did they smut the same when etched?
The coating rubbing off is not an indication of under anodized... rather over anodized. Like I've said in other threads... 2xxx and 7xxx only needs to be ran for 75% of the calculated time, or desolution may result. The clue that some parts were golden supports that.

On the other hand, if all the parts are the same alloy, it could be that you lost partial connection of the large parts. Too much amperage would be delivered to the small parts, and the volts would go up. The small parts would be over anodized, and hence, desolution.

Also, parts that are under anodized will not be a deep black.

[Ready2Dye]

Originally Posted by sswee

Are both parts the same grade of material?

Originally Posted by acidrain

I'm still leaning towards different alloys... did they smut the same when etched?

The parts were both machined from 6061-T6511. I am 110% sure.

They did both smut the same matte titanium color and came nice and shiny clean after desmut.

Originally Posted by sswee

The yellow or golden color usually indicates a heavier coating.
The hazing or color wiping off usually indicates dissolution.

Originally Posted by acidrain

The coating rubbing off is not an indication of under anodized... rather over anodized.

Too much coating and/or dissolution eh?

Originally Posted by acidrain

On the other hand, if all the parts are the same alloy, it could be that you lost partial connection of the large parts. Too much amperage would be delivered to the small parts, and the volts would go up. The small parts would be over anodized, and hence, desolution.

Dissolution sounds like the culprit cuz the larger part did have the crappy connection. And sure, all the amps would be pouring into the small part, which would make for an overkill on that poor little bugger.

Originally Posted by sswee

I didn't see what your tank temp was for the run.

oops! Temp starting was 69° ambient and 67° in the ano bath. When I was finishing it was still 69° in the room but the tank was between 71-72°.

Well these lucky guys have a date with a stripper.

Can't wait for those friggin Ti screws!

After that: No more headaches... yeah right!
Thank you for all your input gentlmen.
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