deanodizing the anodized
 

so, i was looking at some odd anodized aluminum components that i have laying around, and i got to thinking that it might be cool to try and deanodize them. as far as i know, all that needs to be done is to soak the parts in a sodium hydroxide solution - i.e. ajax powder(sodium hydroxide carbonate) and warm water.

before i drop the $3 and go at it - does anyone know if this compromises the structural integrity of the aluminum in any way? i mean i wouldn't want some blingity blang parts if they're going to explode.

if it doesnt, then i wonder if deanodizing a mavic reflex would act to prevent it's tendency to crack at the eyelets.

You could just use sandpaper or have them polished.

All anodizing is, is a layer of aluminum oxide on the outside of the parts (sometimes with dye embedded in it). It's harder than plain aluminum and makes the surface more scratch resistant, but if you dissolve that off of there, the plain aluminum that's left underneath will be fine.

Isn't there a how-to article about this at fixed gear gallery?

I hear oven cleaner will remove anodizing. Something about the lye?

Yeah you can use oven cleaner but itll still need polishing or something after or itll look like ass. Im telling you, sand it or have it polished. Anodizing is very easy to remove.

easyoff oven cleaner takes off anodizing. sprey on, wipe off ten minutes later. later

I've de-anodized headsets and stems using Easy-Off oven cleaner. It still requires a bit of sanding. Then polish with a polishing wheel.

im doing this soon (actually made a post about it yesterday) and i'm planning on buying the stuff dennis used. not that expensive, and i figure something designed to deanodize is gonna be at least a little bit better than something designed to clean ovens.

stripped the threads on a threadless aluminum stem a few months after using easy off to remove the ano. may be unrelated though, apparently i tend to overtighten stuff :p

lye is the common name for sodium hydroxide, although it's not technically pure. that anodizing removing powder is nothing more than pure sodium hydroxide - which is why you should wear gloves and goggles.

sodium hydroxide has a pH of 14 (lye has a pH of 13), so if you injest it, you'd better hope that they can restore your blood's pH (7.4) before your organs are slush. it's extremely caustic, the base equivalent of hydrochloric acid (pH 0).

i sort of wonder if he could have spared himself the new wheelset, if he was able to submerge the wheel to right below the hub flange on top and then on bottom, and then submerged the small "left" and "right" portions of each wheel at the same time.

for the record, i just removed the anodized walls of my rims using the cheapest oven cleaner (lemon fresh scent!) i could find at Kroger's. Applied with a tootbrush, let sit for 10-15 minutes, scrubbed off with some steel wool. took a few reapplications and a bit of time/work, but it looks damn good and was very cheap. yeah, de-anodizer would be lovely but i'd rather hit up the grocery store and grab a 6 of widmer with my can of oven cleaner. you can't get that sorta deal through mail order.

did you do it when the wheel was built up?

built up as in spokes and hubs? yes. built up as in tubes and tires? no.

i only wanted to remove the anodized brake surface, not strip the entire rim, so i had to use a toothbrush and be sorta carfeul with the whole process. but all in all it came out better than i expected. sure beats that ****ty "oops, i used brakes on anodized rims" look.

i meant as in spokes and hubs. would it have been more or less difficult to strip the whole rim?

here's a good introduction to what exactly anodizing is/does

http://www.focuser.com/atm/anodize/anodize99.html

i'd say it would probably have been a little easier to strip the entire rim when not built up because you wouldn't have to worry about nipples and spokes getting in your way. you could just spray that **** everywhere and let it do its work. however, that would mean more scrubbing. so all in all, maybe the ease of application would balance out the work for the amount of area needed to be scrubbed?

i didn't have to worry about scrubbing around each and every nipple (which would suck) because i just did the walls. otherwise i would have torn that **** apart, gone to town with the oven cleaner and steel wool, and tried my hand at wheel building after i was done stripping, hehe.