Bicycle Mechanics - Rust Removal Experiment

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View Full Version : Rust Removal Experiment


Aloe
12-29-10, 03:50 PM
So... After a few years of personal assault on my chain (5 years of winter and summer riding for approximately 15 000 miles), I am looking to perform a little bit of an experiment this upcoming spring. I do not intend to use the same chain again, as I will be buying a new one this may, but I would like to see if it can be cleaned.

Back in one of my terrible freshman level chem courses during college, we touched up on electrolysis and sacrificial metals, and did a really short lab experiment where - blah blah blah - one of the nodes lost mass, the other gained mass.

A list of supplies I have to get'er done is a battery charger, rusty bike chain (Cathode), bucket, water, baking soda, and a sacrificial metal [iron or stainless steel, (Anode)].

*Safety first, obviously, as I'm not trying to blow my place up or get the neighbors to thinking I'm making meth.


My question now is, does anyone here have any experience with electrolytic rust removal? Any comments or concerns?


sideshow_bob
12-29-10, 04:13 PM
Seems like a lot of work, when there are a lot of chemical ways to do it faster and more effectively.

For example, make a solution of sodium hydroxide dissolve some kind of zinc into it, zinc oxide, zinc phosphate ... whatever you can get your hands on. Put the chain in and bring it to the boil.

Or just stick the chain in a jar of phosphoric acid or citric acid ... etc etc.

aljohn
12-29-10, 04:30 PM
I've heard that Coca Cola does a good job, probably more expensive than the proper cleaners.... ;-)


Aloe
12-29-10, 05:54 PM
Seems like a lot of work, when there are a lot of chemical ways to do it faster and more effectively.
For example, make a solution of sodium hydroxide dissolve some kind of zinc into it, zinc oxide, zinc phosphate ... whatever you can get your hands on. Put the chain in and bring it to the boil.

Really? That sounds interesting. I'll have to look into that.

I'm just looking to make a little project out of the chain; the little things in life make me happy.

wrk101
12-29-10, 06:03 PM
Search is your friend. Yes, someone has a whole thread on electrolytic rust removal. Sodium hydroxide does not work well on rust. There are dozens of threads on using various acids, acid of choice is oxalic acid.

Coca cola is just an expensive source of phosphoric acid. Others use vinegar (acetic acid) as well.


Boiling sodium hydroxide is pretty hazardous.

sideshow_bob
12-29-10, 10:33 PM
The NaOH is just to dissolve the ZnO, which I don't think is soluable in weak acids. The Zn2+ is what is removing the rust.

davidad
12-30-10, 08:32 AM
Unless you kept the chain very clean and lubed you are going to need to replace the drive train (cogs and rings) after 15k miles.

Aloe
12-30-10, 05:26 PM
I did a search for both chain rust and electrolysis and it came up blank, but thank you.

Yeah, everything is being replaced, I just wanted to try something out for s***s and giggles.

Desonate
12-30-10, 06:11 PM
I've done some electrolytic rust removal on non-bike related items before. First test object was a rusted metal ruler and it came out pretty clean. I've built my rust bucket based on this (http://www.instructables.com/id/Electrolytic-Rust-Removal-aka-Magic/) guide with some minor changes.

The washing soda (sodium carbonate) can be substituted with baking soda (sodium bicarbonate) by heating the washing soda. This can be done by baking or just mixing it with boiling water. Other things to note is, do not put stainless steel or chrome and a couple of other metals. Rebar can be obtained from construction sites :innocent:

FastJake
12-30-10, 06:22 PM
Sorry to hijack the thread... but what's the best way you've found to remove rust? Folks are mentioning vinegar, Coca Cola, etc. My winter bike is covered in rust and I'd really like to get some of the parts cleaned up and protected so this doesn't happen again. QR skewers, nuts and bolts, that sort of thing. The chain looks horrible too.

wrk101
12-30-10, 08:00 PM
I did a search for both chain rust and electrolysis and it came up blank, but thank you.

Yeah, everything is being replaced, I just wanted to try something out for s***s and giggles.

I just did a search and came up with 181 hits. The key is do not use the search through the forum. Go to google, type in: electrolysis site:bikeforums.net

I use google this way to search any forum. Lots of forums have search challenges.

Here's one good one:
http://www.bikeforums.net/showthread.php/508440-Electrolysis-for-rust-removal

This one is good too:

http://www.bikeforums.net/showthread.php/524505-76-Varsity-B-amp-A-Electrolysis-rust-removal

LeftinFlint
12-30-10, 08:20 PM
You can try this. There are variations all over the interwebs. http://www.youtube.com/watch?v=PhXcwRyGVsU

FBinNY
12-30-10, 09:56 PM
The horse is out of the barn.

The rust itself isn't the problem, it's the loss of strength by way of the steel lost to rust. You can remove the rust chemically, mechanically or electrically, or by whatever means you want, but it's only cosmetic. You cannot reverse rust and restore strength any more than you can un-ring a bell.

The objective in managing rust is to prevent it in the first place.

JohnDThompson
12-31-10, 11:38 AM
I use a wire wheel to remove the loose rust, then let the item soak in standard white vinegar from the grocery store. It's worked pretty well for me, anyway.