Sodium Hydroxide to strip anodization off rims?
06-19-23, 02:37 AM
#1
Newbie
Thread Starter
Sodium Hydroxide to strip anodization off rims?
I know any removal of anodization will late a layer of material with it, but will the lye weaken the rim in any other way? I'm mainly worried about chemical reaction.
06-19-23, 07:28 AM
#2
Senior Member
Join Date: Feb 2022
Location: GMT-5
Posts: 988
Mentioned: 1 Post(s)
Tagged: 0 Thread(s)
Quoted: 573 Post(s)
Liked 434 Times
in
287 Posts
Sodium Hydroxide is what is used to strip off anodized car mags and motorcycle parts, so would also apply to your rims.
It might be a good idea to strip the wheel down to just the rim, hub and spokes removed.
It might be a good idea to strip the wheel down to just the rim, hub and spokes removed.
Likes For soyabean:
06-19-23, 07:34 AM
#3
Senior Member
Join Date: Oct 2022
Posts: 1,378
Bikes: a couple
Mentioned: 15 Post(s)
Tagged: 0 Thread(s)
Quoted: 563 Post(s)
Liked 871 Times
in
458 Posts
Lye will eat anything right up to and including dental fillings. It is an alkali. I've used t a lot to remove ugly anno before polishing. After using, make sure you neutralize the lye before proceeding. Vinegar in a spray bottle followed with water works.
06-19-23, 08:31 AM
#4
Senior Member
Join Date: Feb 2012
Location: Rochester, NY
Posts: 18,180
Bikes: Stewart S&S coupled sport tourer, Stewart Sunday light, Stewart Commuting, Stewart Touring, Co Motion Tandem, Stewart 3-Spd, Stewart Track, Fuji Finest, Mongoose Tomac ATB, GT Bravado ATB, JCP Folder, Stewart 650B ATB
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 4245 Post(s)
Liked 3,990 Times
in
2,372 Posts
Having seen a number of home stripped anodizing results I will only add that don't be surprised if the rim looks pretty bad after. If the rim has eyelets take a lot of care rinsing the lye off there. Andy
__________________
AndrewRStewart
AndrewRStewart
Likes For Andrew R Stewart:
06-19-23, 08:46 AM
#5
Mad bike riding scientist
Join Date: Nov 2004
Location: Denver, CO
Posts: 27,498
Bikes: Some silver ones, a red one, a black and orange one, and a few titanium ones
Mentioned: 153 Post(s)
Tagged: 1 Thread(s)
Quoted: 6296 Post(s)
Liked 4,333 Times
in
2,429 Posts
Sodium hydroxide is more highly reactive with the aluminum than with the aluminum oxide layer that makes up the anodized surface. That is likely the cause of the poor results. Because of the higher reaction rate for aluminum, I would also be dubious about the strength of a thin aluminum part like a rim following treatment. There is no way to preferentially control the reaction.
__________________
Stuart Black
Plan Epsilon Around Lake Michigan in the era of Covid
Old School…When It Wasn’t Ancient bikepacking
Gold Fever Three days of dirt in Colorado
Pokin' around the Poconos A cold ride around Lake Erie
Dinosaurs in Colorado A mountain bike guide to the Purgatory Canyon dinosaur trackway
Solo Without Pie. The search for pie in the Midwest.
Picking the Scablands. Washington and Oregon, 2005. Pie and spiders on the Columbia River!
Stuart Black
Plan Epsilon Around Lake Michigan in the era of Covid
Old School…When It Wasn’t Ancient bikepacking
Gold Fever Three days of dirt in Colorado
Pokin' around the Poconos A cold ride around Lake Erie
Dinosaurs in Colorado A mountain bike guide to the Purgatory Canyon dinosaur trackway
Solo Without Pie. The search for pie in the Midwest.
Picking the Scablands. Washington and Oregon, 2005. Pie and spiders on the Columbia River!
06-19-23, 09:00 AM
#6
Senior Member
Join Date: Oct 2022
Posts: 1,378
Bikes: a couple
Mentioned: 15 Post(s)
Tagged: 0 Thread(s)
Quoted: 563 Post(s)
Liked 871 Times
in
458 Posts
Sodium hydroxide is more highly reactive with the aluminum than with the aluminum oxide layer that makes up the anodized surface. That is likely the cause of the poor results. Because of the higher reaction rate for aluminum, I would also be dubious about the strength of a thin aluminum part like a rim following treatment. There is no way to preferentially control the reaction.
Garbage bag and oven cleaner were the method used. Oven cleaner is lye based but not pure lye. Does the job without the scars of leaving it in too long. If you don't neutralize the lye, it will keep eating.
Your mileage may vary.
The wheel has to be dissembled.
06-19-23, 09:11 AM
#7
Mad bike riding scientist
Join Date: Nov 2004
Location: Denver, CO
Posts: 27,498
Bikes: Some silver ones, a red one, a black and orange one, and a few titanium ones
Mentioned: 153 Post(s)
Tagged: 1 Thread(s)
Quoted: 6296 Post(s)
Liked 4,333 Times
in
2,429 Posts
Been doing this since the 70's. Done 15 or 20 rims with no issue.
Garbage bag and oven cleaner were the method used. Oven cleaner is lye based but not pure lye. Does the job without the scars of leaving it in too long. If you don't neutralize the lye, it will keep eating.
Your mileage may vary.
The wheel has to be dissembled.
Garbage bag and oven cleaner were the method used. Oven cleaner is lye based but not pure lye. Does the job without the scars of leaving it in too long. If you don't neutralize the lye, it will keep eating.
Your mileage may vary.
The wheel has to be dissembled.
As to the process, no matter what the concentration of sodium hydroxide, it will react with the aluminum more readily and at a higher rate than with the aluminum oxide. The result will be an unknown change in the structure of the rim. Further, sodium hydroxide may not even be removing the anodized layer since conditions to form the sodium aluminate are quite severe. It’s more likely that the dye used on anodized rims is being decolored rather than the anodized layer is being removed.
__________________
Stuart Black
Plan Epsilon Around Lake Michigan in the era of Covid
Old School…When It Wasn’t Ancient bikepacking
Gold Fever Three days of dirt in Colorado
Pokin' around the Poconos A cold ride around Lake Erie
Dinosaurs in Colorado A mountain bike guide to the Purgatory Canyon dinosaur trackway
Solo Without Pie. The search for pie in the Midwest.
Picking the Scablands. Washington and Oregon, 2005. Pie and spiders on the Columbia River!
Stuart Black
Plan Epsilon Around Lake Michigan in the era of Covid
Old School…When It Wasn’t Ancient bikepacking
Gold Fever Three days of dirt in Colorado
Pokin' around the Poconos A cold ride around Lake Erie
Dinosaurs in Colorado A mountain bike guide to the Purgatory Canyon dinosaur trackway
Solo Without Pie. The search for pie in the Midwest.
Picking the Scablands. Washington and Oregon, 2005. Pie and spiders on the Columbia River!
Last edited by cyccommute; 06-19-23 at 09:24 AM.
Likes For cyccommute:
06-19-23, 09:29 AM
#8
Clark W. Griswold
Join Date: Mar 2014
Location: ,location, location
Posts: 14,026
Bikes: Foundry Chilkoot Ti W/Ultegra Di2, Salsa Timberjack Ti, Cinelli Mash Work RandoCross Fun Time Machine, 1x9 XT Parts Hybrid, Co-Motion Cascadia, Specialized Langster, Phil Wood Apple VeloXS Frame (w/DA 7400), R+M Supercharger2 Rohloff, Habanero Ti 26
Mentioned: 56 Post(s)
Tagged: 0 Thread(s)
Quoted: 4527 Post(s)
Liked 4,230 Times
in
2,830 Posts
The real question is why do you keep buying anodized rims? Lots of rims out there that aren’t anodized.
As to the process, no matter what the concentration of sodium hydroxide, it will react with the aluminum more readily and at a higher rate than with the aluminum oxide. The result will be an unknown change in the structure of the rim. Further, sodium hydroxide may not even be removing the anodized layer since conditions to form the sodium aluminate are quite severe. It’s more likely that the dye used on anodized rims is being decolored rather than the anodized layer is being removed.
As to the process, no matter what the concentration of sodium hydroxide, it will react with the aluminum more readily and at a higher rate than with the aluminum oxide. The result will be an unknown change in the structure of the rim. Further, sodium hydroxide may not even be removing the anodized layer since conditions to form the sodium aluminate are quite severe. It’s more likely that the dye used on anodized rims is being decolored rather than the anodized layer is being removed.
06-19-23, 09:32 AM
#9
Senior Member
Join Date: Oct 2022
Posts: 1,378
Bikes: a couple
Mentioned: 15 Post(s)
Tagged: 0 Thread(s)
Quoted: 563 Post(s)
Liked 871 Times
in
458 Posts
The real question is why do you keep buying anodized rims? Lots of rims out there that aren’t anodized.
As to the process, no matter what the concentration of sodium hydroxide, it will react with the aluminum more readily and at a higher rate than with the aluminum oxide. The result will be an unknown change in the structure of the rim. Further, sodium hydroxide may not even be removing the anodized layer since conditions to form the sodium aluminate are quite severe. It’s more likely that the dye used on anodized rims is being decolored rather than the anodized layer is being removed.
As to the process, no matter what the concentration of sodium hydroxide, it will react with the aluminum more readily and at a higher rate than with the aluminum oxide. The result will be an unknown change in the structure of the rim. Further, sodium hydroxide may not even be removing the anodized layer since conditions to form the sodium aluminate are quite severe. It’s more likely that the dye used on anodized rims is being decolored rather than the anodized layer is being removed.
It was mostly for friends. When you can get one blue outer and one green one, you make them both shiny.
Other times it was when could get one dark anno and one something else. mostly from need
06-19-23, 09:38 AM
#10
Senior Member
Join Date: Oct 2022
Posts: 1,378
Bikes: a couple
Mentioned: 15 Post(s)
Tagged: 0 Thread(s)
Quoted: 563 Post(s)
Liked 871 Times
in
458 Posts
I have an experiment going now. hard anno matrix in a clear bag doused in oven cleaner.
I'll check it in a couple of hours.
I'll check it in a couple of hours.
Likes For Schweinhund:
06-19-23, 09:54 AM
#11
ignominious poltroon
Join Date: Jan 2022
Posts: 4,215
Mentioned: 3 Post(s)
Tagged: 0 Thread(s)
Quoted: 2319 Post(s)
Liked 3,548 Times
in
1,870 Posts
Likes For Polaris OBark:
06-19-23, 10:00 AM
#12
ignominious poltroon
Join Date: Jan 2022
Posts: 4,215
Mentioned: 3 Post(s)
Tagged: 0 Thread(s)
Quoted: 2319 Post(s)
Liked 3,548 Times
in
1,870 Posts
I ruined a centrifuge rotor (by accident) with a sodium hydroxide spill. I wouldn't take a chance on wheels I cared about (which is any wheel that I would ride).
Likes For Polaris OBark:
06-19-23, 10:14 AM
#13
Senior Member
Join Date: Sep 2004
Location: Chicago area
Posts: 2,578
Bikes: Airborne "Carpe Diem", Motobecane "Mirage", Trek 6000, Strida 2, Dahon "Helios XL", Dahon "Mu XL", Tern "Verge S11i"
Mentioned: 23 Post(s)
Tagged: 0 Thread(s)
Quoted: 996 Post(s)
Liked 596 Times
in
407 Posts
It might seem that it keeps going, but the reaction will stop when all of one (or more) of the reactants has been consumed. The limiting factor is probably the NaOH.
Here's the reaction for aluminum and sodium hydroxide:
2NaOH+2Al+2H2O→2NaAlO2+2H2
Notice that one of the products is hydrogen gas... maybe enough to burn.
Here's the reaction for aluminum and sodium hydroxide:
2NaOH+2Al+2H2O→2NaAlO2+2H2
Notice that one of the products is hydrogen gas... maybe enough to burn.
06-19-23, 10:29 AM
#15
Senior Member
Join Date: Oct 2022
Posts: 1,378
Bikes: a couple
Mentioned: 15 Post(s)
Tagged: 0 Thread(s)
Quoted: 563 Post(s)
Liked 871 Times
in
458 Posts
It might seem that it keeps going, but the reaction will stop when all of one (or more) of the reactants has been consumed. The limiting factor is probably the NaOH.
Here's the reaction for aluminum and sodium hydroxide:
2NaOH+2Al+2H2O→2NaAlO2+2H2
Notice that one of the products is hydrogen gas... maybe enough to burn.
Here's the reaction for aluminum and sodium hydroxide:
2NaOH+2Al+2H2O→2NaAlO2+2H2
Notice that one of the products is hydrogen gas... maybe enough to burn.
Thank you for the heads up.
Likes For Schweinhund:
06-19-23, 12:22 PM
#17
Senior Member
Join Date: Oct 2022
Posts: 1,378
Bikes: a couple
Mentioned: 15 Post(s)
Tagged: 0 Thread(s)
Quoted: 563 Post(s)
Liked 871 Times
in
458 Posts
Ok, so here goes.
Best guess is give it about 3 hours with the oven cleaner and I could polish this thing in an hour or so including sanding.
wheel is a matrox 550 out of the bin
wheel
wjeel with 1 minute of sanding with 1500 grit and no oven cleaner
2 hours in oven cleaner and about 1 minute with 1500grit
Best guess is give it about 3 hours with the oven cleaner and I could polish this thing in an hour or so including sanding.
wheel is a matrox 550 out of the bin
wheel
wjeel with 1 minute of sanding with 1500 grit and no oven cleaner
2 hours in oven cleaner and about 1 minute with 1500grit
