Anodize removal, any pitfalls

[apes]

I have an 80% receiver that was anodized prior to completion (it came anodized). I now want to engrave it but when I am finished I do not want the engravings to be bright or blatant but all the samecolor as the
anodization and I would like the new holes (trigger, selector etc). to be hardened.

My question is if I were to remove the anodizating via the use of Ez-off or any other lye based solutions, prior to engraving, would any metal be removed from the holes so that after reassembled, the pins on the selector / trigger etc would fit loosely? Ideally when reanodized the holes would be hardened. In other words is any metal removed during the anodizing removal process/
thanks

[Rusty Scabbard]

I've removed type 2 anodize in Lye solution without problems. 6061 Al, and I did not leave it in a second longer than it took to dissolve the anodize. It only took about a minute or so. My parts were not an AR receiver, but there were a couple pins I re-installed after reanodizing, and they were not looser than before. If it's degreased well before starting, and the stripping bath kept turbulent so you're not waiting a long time for the nooks and crannies to strip, I doubt you would have any problems. Being and 80%'er, you could also wax, paint or somehow protect the selector and pin holes before dipping into the bath.

[kcstott]

yes it will remove metal. In all reality not much. don't use or soak any longer then needed to remove the anodize. Ez off I'm not sure of I just used 100% sodium hydroxide about 1/2 teaspoon full per gallon.
Warm water helps the reaction

[Rusty Scabbard]

I did my parts in very hot water with about a teaspoon of lye in a gallon. Had the part on a threaded rod so I could shake it around to keep it mixed. Most anodize stripped off in seconds but it took a half a minute or so to get it all stripped off near the corners. Use a bucket of rinse water or a running stream to flush it off quick as you go to see if it's done. And sorry to flog the safety-horse... but be sure to wear googles.

[sffred]

Easy off oven cleaner

[DEF23]

You don't need to remove the anno to do any etching on the lower.

I have done a couple right through the anno without any bad results.

In fact, depending upon your templates, it sometimes comes out clearer and sharper than on plain aluminum.