"De-Anodizing" Some Flashlights

\"De-Anodizing\" Some Flashlights

I wanted to prep a few flashlights for different finishes and some modifications, so I tried my hand at taking the anodizing off via the Red Devil Lye method. This was my first time doing this - it was surprisingly easy and yielded outstanding results.

I found it deceiving on the first few parts. It looked as if it wasn't coming off all the way. When I washed them off with a little soap and a mild bit of Scotch-Brite, they looked like virgin Al.

Pictures coming.

Re:

For knurls, try a wire brush along with the lye. You have to get it all off for it to re-anodize properly.

Larry

Re:

Would Drano suffice? Same, or similar chemical?

Bill

Re:

Bullzeybill,

Yes, drano works! (Recently did it.) NaOH is NaOH. The anodizing bath chemicals are very caustic, and care
ful masking of your parts is critical. Caustics etch/dissolve aluminum. Coloration is a dying (almost as in "food color") process, following the anodizing, which is a surface conversion to Al2O3. The chemistry is strait forward, getting it right is a challlenge sometimes, even for the pros!

Larry

Re:

I have had very good luck with it.
Yes, some AL tends to "stain" with the color of the HA.
Make sure not to make the solution too strong, it will pit the AL alot, and make it hell to polish.

Re: Deanodize

Wow, perfect timing for a great tip. I have a 2C tailcap where I need to make electrical contact. I dreaded the thought of hacking it up with steel wool or a Dremel tool. I found some off brand drain cleaner in the closest and sure enough, it's main ingredient is NaOH. Poured a little in and rubbed it with a cotton swab. It didn't look like it was working at first, but the swab was black so I figured a few more applications were in order. It wasn't until the fifth one that the Al started to appear. Two more 'wash' cycles and I was the proud owner of a clean tailcap. Thank you for a timely and super tip.

Violà - we be conducting electrons now:

Re:

[ QUOTE ]
tvodrd said:
Bullzeybill,

Yes, drano works! (Recently did it.) NaOH is NaOH. The anodizing bath chemicals are very caustic, and care
ful masking of your parts is critical. Caustics etch/dissolve aluminum. Coloration is a dying (almost as in "food color") process, following the anodizing, which is a surface conversion to Al2O3. The chemistry is strait forward, getting it right is a challlenge sometimes, even for the pros!

Larry


[/ QUOTE ]

What did you use to mask the areas you didn't want damaged by the lye?
oldgrandpajack

Re:

oldgranpajack,

Rubber stoppers are great for masking I.D.s and tightly-stretched vinyl tape sometimes works for O.D.s. Caswells sells masking laquers which I've never tried. One anodizer I know uses laquers, and his price goes up as it is labor intensive.

Larry

Re: \"De-Anodizing\" Some Flashlights

This is right on time.

EvilLithiumMan -

Same question for you. How did you protect the leading edge of the end cap? It looks better than a factory grade cut line.

Re: \"De-Anodizing\" Some Flashlights

Icebreak,

It only looks good because of the angle of the shot. I simply poured a small amount of cleaner into the tailcap each cycle. After all, it was only the bottom of the tailcap that I wanted cleaned. As a matter of fact, because I always poured from the same point, there was deanodizing along the inner wall of the cap. I just made sure it wasn't included in the picture. /ubbthreads/images/graemlins/smile.gif

"And now you know the rest of the story":

Re: \"De-Anodizing\" Some Flashlights

I used clay or playdough to cover the parts I didnt want stripped.
This works well for grooves and such.

Tape also works well, but, be aware, it tends to leave alittle sticky glue from the tape in the water, and gets on the AL sometimes. Not a big deal really, just clean it off well.

Here is some HA stripping I have done with LYE.
Arc AAA

Various parts:

Re: \"De-Anodizing\" Some Flashlights

EvilLithiumMan -

/ubbthreads/images/graemlins/grin.gif Thanks for the "Paul Harvey" on that.

Thanks, jtice. I would never have thought of that.