How do you de-anodize aluminum
#16
BEst way to strip the anodizing is to have a shop do it. 2nd best is to bead blast it.
#19
De anodizing
Oven cleaner dosen't work that good. I have used Drano gel and let it sit for 3 hours. Result...beautiful de-anodized parts with zero pitting.
#21
yep
I was searching the forum for a way to do it myself, found a good Youtube video, figured I'd share. Didn't see the post date. No big deal, lol.
#22
Tech Initiate
It doesn't matter how old the thread is if you're contributing to it.
#23
Tech Initiate
still a useful subject and it answered my questions. Thx guys
#24
Tech Regular
iTrader: (2)
Here's my procedure, documented in more detail with my current Turbo Optima build here. I didn't experience any pitting with any of the parts (with this build or my previous CYANide build) by doing this procedure.
http://www.rc10talk.com/viewtopic.php?f=30&t=21530
1. Spray Easy-Off Heavy Duty oven cleaner on your anodized parts, let them soak for a while in a plastic pail or something. It only takes 5 or 10 minutes before you'll see the anodize coloring coming right off. Don't breathe the nasty smell and don't get Easy-Off on your skin, it will begin to itch. Rubber gloves and ventilation are important.
2. Rinse off the parts in hot water and re-spray any areas that still have areas of anodizing. I use a toothbrush to help get into the nooks & crannies.
3. Once all the anodizing is gone, you'll see either a dull silver or a charcoal grey finish...I think it depends on the quality of the aluminum. Now you get to work with the polishing.
4. Polishing aluminum is the same as for any other material; you wet-sand with progressively finer grits until you achieve your desired level of glossiness. It ain't easy and you won't score any points by taking short-cuts. Start with 400-grit and wet-sand, then repeat with 600, 800, 1000 & perhaps even 1500-grit. Some parts, I stop at 1000, some at 1500. I don't go any further (rubbing & polishing compound) if I'm planning to have the parts re-anodized, but if I want a nice glossy almost-chrome-like finish, I'll do step 5.
5. Rub down the parts with automotive rubbing compound; 3M or Turtle Wax or whatever. I prefer the paste that comes in little tubs. Repeat that procedure with automotive polishing compound. Lastly, I'll repeat with Nu-Finish Scratch Doctor, which gets the parts very nice and shiny. Again, step 5 isn't really necessary if you're planning on re-anodizing the parts.
http://www.rc10talk.com/viewtopic.php?f=30&t=21530
1. Spray Easy-Off Heavy Duty oven cleaner on your anodized parts, let them soak for a while in a plastic pail or something. It only takes 5 or 10 minutes before you'll see the anodize coloring coming right off. Don't breathe the nasty smell and don't get Easy-Off on your skin, it will begin to itch. Rubber gloves and ventilation are important.
2. Rinse off the parts in hot water and re-spray any areas that still have areas of anodizing. I use a toothbrush to help get into the nooks & crannies.
3. Once all the anodizing is gone, you'll see either a dull silver or a charcoal grey finish...I think it depends on the quality of the aluminum. Now you get to work with the polishing.
4. Polishing aluminum is the same as for any other material; you wet-sand with progressively finer grits until you achieve your desired level of glossiness. It ain't easy and you won't score any points by taking short-cuts. Start with 400-grit and wet-sand, then repeat with 600, 800, 1000 & perhaps even 1500-grit. Some parts, I stop at 1000, some at 1500. I don't go any further (rubbing & polishing compound) if I'm planning to have the parts re-anodized, but if I want a nice glossy almost-chrome-like finish, I'll do step 5.
5. Rub down the parts with automotive rubbing compound; 3M or Turtle Wax or whatever. I prefer the paste that comes in little tubs. Repeat that procedure with automotive polishing compound. Lastly, I'll repeat with Nu-Finish Scratch Doctor, which gets the parts very nice and shiny. Again, step 5 isn't really necessary if you're planning on re-anodizing the parts.
#25
Tech Master
iTrader: (10)
I basically did as posted above on my TC6 parts. I soaked them for 10-20 minutes in Easy-Off. MOST of it simply rinsed off.... there were a few spots where I had to gently rub the area with a shop rag (wet with Easy-Off). After that, I rinsed with hot water and dried the parts with a towel.
I did not do a sandpaper cycle.... although the parts came out looking nice, I now wish that I had done it!
Terry cloths and Mother's Aluminum Polish put a NIIICE shine on them
I did not do a sandpaper cycle.... although the parts came out looking nice, I now wish that I had done it!
Terry cloths and Mother's Aluminum Polish put a NIIICE shine on them
#26
#27
Tech Master
iTrader: (1)
Just a couple of extracts from wiki:
"...the coating [Al anodizing] is susceptible to chemical dissolution in the presence of high and low pH chemistry, which results in stripping the coating and corrosion of the substrate."
and
"Because the dye is only superficial, the underlying oxide may continue to provide corrosion protection even if minor wear and scratches may break through the dyed layer."
Just a thought to consider if you need your "de-anodizing" method is removing just the color or the actual oxide.
"...the coating [Al anodizing] is susceptible to chemical dissolution in the presence of high and low pH chemistry, which results in stripping the coating and corrosion of the substrate."
and
"Because the dye is only superficial, the underlying oxide may continue to provide corrosion protection even if minor wear and scratches may break through the dyed layer."
Just a thought to consider if you need your "de-anodizing" method is removing just the color or the actual oxide.
#28
Tech Regular
iTrader: (2)
Just a couple of extracts from wiki:
"...the coating [Al anodizing] is susceptible to chemical dissolution in the presence of high and low pH chemistry, which results in stripping the coating and corrosion of the substrate."
and
"Because the dye is only superficial, the underlying oxide may continue to provide corrosion protection even if minor wear and scratches may break through the dyed layer."
Just a thought to consider if you need your "de-anodizing" method is removing just the color or the actual oxide.
"...the coating [Al anodizing] is susceptible to chemical dissolution in the presence of high and low pH chemistry, which results in stripping the coating and corrosion of the substrate."
and
"Because the dye is only superficial, the underlying oxide may continue to provide corrosion protection even if minor wear and scratches may break through the dyed layer."
Just a thought to consider if you need your "de-anodizing" method is removing just the color or the actual oxide.
http://www.finishing.com/2000-2199/2076.shtml
Sodium Hydroxide (NaOH) is a chemical that will remove anodizing, and is one of the components in Easy-Off HD Oven Cleaner:
http://www.rbnainfo.com/productpro/P...=PL&template=1
At any rate, it's possible to physically remove the layer of anodizing (sanding/bead-blasting) but since anodizing is extremely hard, you'll be spending a great deal of time & effort doing it. Either way, you're left with a rough surface that requires the aforementioned wet-sanding and/or polishing to re-prep the surface properly.
I'm fairly certain anodizing is more than just a layer of color; it's a chemical process that changes the outer surface of the aluminum while coloring it at the same time. I doubt you can strip the color while leaving the anodizing behind.
#29
Tech Master
iTrader: (1)
I personally don't believe everything I read on Wikipedia. Here's a better forum topic on the matter:
http://www.finishing.com/2000-2199/2076.shtml
Sodium Hydroxide (NaOH) is a chemical that will remove anodizing, and is one of the components in Easy-Off HD Oven Cleaner:
http://www.rbnainfo.com/productpro/P...=PL&template=1
At any rate, it's possible to physically remove the layer of anodizing (sanding/bead-blasting) but since anodizing is extremely hard, you'll be spending a great deal of time & effort doing it. Either way, you're left with a rough surface that requires the aforementioned wet-sanding and/or polishing to re-prep the surface properly.
I'm fairly certain anodizing is more than just a layer of color; it's a chemical process that changes the outer surface of the aluminum while coloring it at the same time. I doubt you can strip the color while leaving the anodizing behind.
http://www.finishing.com/2000-2199/2076.shtml
Sodium Hydroxide (NaOH) is a chemical that will remove anodizing, and is one of the components in Easy-Off HD Oven Cleaner:
http://www.rbnainfo.com/productpro/P...=PL&template=1
At any rate, it's possible to physically remove the layer of anodizing (sanding/bead-blasting) but since anodizing is extremely hard, you'll be spending a great deal of time & effort doing it. Either way, you're left with a rough surface that requires the aforementioned wet-sanding and/or polishing to re-prep the surface properly.
I'm fairly certain anodizing is more than just a layer of color; it's a chemical process that changes the outer surface of the aluminum while coloring it at the same time. I doubt you can strip the color while leaving the anodizing behind.
NaOH...basic solution (high pH)
You are correct about anodizing being more than just a color, but it is not a color. The anodizing is the growth of the oxide. The color is a dye that fills in the oxide pores.
#30
This thread helped me quite a bit..
I set up an anodizing station in my shop with some extra electro forming equipment. So far I just did a couple small items that were already anodized. First one I used grease lightning to remove the ano...worked amazing..but when I tried to re-dye it..it didn't work at all. Apparently the pores of the ano were still sealed..and the only way to redo the surface is by removing and polishing the piece.
In this case,,you don't need to bother with the oven cleaner since you will be polishing the coating off anyway..
And RiT dye works wonders for anodizing..
I set up an anodizing station in my shop with some extra electro forming equipment. So far I just did a couple small items that were already anodized. First one I used grease lightning to remove the ano...worked amazing..but when I tried to re-dye it..it didn't work at all. Apparently the pores of the ano were still sealed..and the only way to redo the surface is by removing and polishing the piece.
In this case,,you don't need to bother with the oven cleaner since you will be polishing the coating off anyway..
And RiT dye works wonders for anodizing..