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Alan_Myers
04-14-2005, 04:59 AM
Hi all,

Okya This might be a a bit silly, but does anyone know how to remove colored anodizing from an aluminum part?

I'm installing some Aeroquip lines and I really hate the red/blue coloring that's often used. Nearly all fittings I've been able to find in a nickel finish.

But, Weber banjo to 6AN hose ends seem to <u>only</u> come in red/blue. Soooo, anyone know how to remove the red/blue to leave a nice, plain, aluminum finish?

Thanks in advance!

Alan

04-14-2005, 08:01 AM
Alan, Easy-Off Oven Cleaner works, using several applications. Beware, the underlying aluminum will need to be polished afterwards.

Bill

dklawson
04-14-2005, 09:22 AM
As stated above, anything that removes the dye will leave the aluminum unprotected. FYI, anodizing is the electrolytic build up of aluminum oxide on the underlying metal. Once the oxide film is built up, the part is put in a dye bath so the pores of the aluminum oxide soak up the color. The only way to get the dye out is to ruin/remove the oxide layer using a caustic (like oven cleaner).

BOXoROCKS
04-14-2005, 12:22 PM
Actually..wrong..O. A buffing wheel with the black, cant remember the name, compound will do the job and leave a nice polish. I remember the name, emery cake. Caustic is a no..no.
Another brilliant answer by BoRs /ubbthreads/images/graemlins/laugh.gif

R6MGS
04-14-2005, 04:34 PM
Not sure how to remove it but I hate that red/blue colouring too. Just about every nice Muscle car that shows up at the local cruise has something with the blue/red coloring...It looks horrible I'd much rather have it just polished aluminum

Zack

Alan_Myers
04-14-2005, 05:37 PM
Hi,

Whew! I'm relieved that at least one other person feels like me about the colorful fittings.

"Hey, it's under the hood! Who cares!?"

<u>"I do!"</u>

Good news is many fittings are now being made with a nickel finish by the various manufacturers: Aeroquip, Russell, Earl's, Summit, etc. Unfortunately, nickel finish often costs more!

Ain't cheap to begin with! Especially when you start to add up all the fittings in a fuel system: tank to filter, filter to pump, pump to pressure regulator, pressure regulator to splitter, splitter to carb x 2.

FYI, there are also now black anodized fittings made specifically to fit black nylon braid covered hose, which is lighter and a little less expensive than the stainless stuff. Probably not as abrassive, too, but still has a high burst strength and is supposed to be tough. I might try it the next time I install an oil cooler.

Thanks for the suggestions... I'd never have thought of oven cleaner! I agree it's pretty corrossive and polishing might be a better approach. Unfortunately these fittings are complex and may not be easily polished. So, I might try a combination. I've got a couple small, spare anodized pieces I can experiment on. The threads, internal and sealing surfaces which are hidden once the piece is attached can just be left "as is".

I would clear coat the aluminum when all is done. I do this often with motorcycle parts, where a lot more highly polished aluminum tends to be used, with clear engine paint.

Thanks again!

Alan

Alan_Myers
04-22-2005, 07:34 PM
Hi all,

After trying a few different things, Easy Off seems to be the most efficient way to remove anodizing.

WARNING! Nasty stuff! Don't breath the fumes, best used out of doors when there is a little bit of a breeze.

I put a small, extra fitting in an empty plastic margarine tub, sprayed on a bit of Easy Off and worked it around with an old toothbrush. Let it sit for a very short, then rinsed with lots of water. It took three applications to get to bare aluminum, but it worked! A little follow up with polish makes the piece look great.

Now, if I can just work up the nerve to spray some on those expensive Weber fittings that just arrived today.... ;-)

We'll see if some high temp clear coat adequately keeps the now-bare aluminum from oxidizing with "white rust".

Cheers!

Alan

P.S. Okay, I worked up the nerve and stripped the anodizing off the Weber banjo fittings, too.

A tip if you ever try this... only leave the Easy Off on the part for a very short time, brush a little then rinse with cold water. Do several applications this way to remove all the anodizing. The reason is that some aluminum seems to oxidize fast while other pieces stayed nice and shiny. That makes for more work later polishing everything back up to an even finish.

Any residual polish was removed to prep for clear coat. Disk brake cleaner spray works quickly for this and evaporates fast. Parts have now been assembled, clear coated and are hanging up to dry. They look great! Almost as shiny as the nickel plated fittings.

Much better than the red/blue anodized finish! (Which I think has traditionally been used in aircraft fittings as a safety feature. It would be pretty easy to spot anything not properly re-connected.)

A.