Adam65

I am restoring Raleigh Mountain Tour Tamarack. Condition is generally very good. Rear wheel (which is perfectly true and spins beautifully) is really rusty.
As I don't want to fill huge tank with oxalic acid to put the whole thing in there, I will have to turn the wheel good several times to fix all rim around-that will take many days.
Is it safe to warm oxalic acid up (and how ?) to speed the process up ?

GravelMN

Looking at that wheel, I'm not sure you're going to be happy with the results even when the rust is gone.

Warming the oxalic acid might speed the process slightly but is also going to increase the rate of evaporation and the amount of fumes/odor created. Unless you are working in a cold location, I don't think it would be worth the effort. A better approach would be to wet the whole rim with the oxalic acid, then wrap it with a couple layers of paper towels soaked in the solution, followed by a layer of plastic wrap. There are also gel versions of rust remover (Naval Jelly being a common one) that will cling to the surfaces.

I'm not sure (somebody else chime in here) if it is a good idea to soak the nipples and spoke ends in an acid bath unless you plan to completely disassemble the wheel to neutralize and rinse each part. I can see the OA seeping into the threads and drying only to cause problems down the road in humid weather or wet riding conditions. As the nipples are probably brass or white brass, they might not hold up to the OA like the steel spokes/rim will.

Honestly, I'd consider disassembling the wheel and replacing the rim and nipples, maybe spokes too. You will get a better looking result that you know is sound and it will improve your braking as well. If you aren't terribly attached to keeping the original hubs, a replacement wheel or a better used wheel would be good options.

cyccommute 

First, warming the oxalic acid isn't going to cause any problems. The issue will be keeping it warm for long enough to do any good. Applying it like GravelMN suggested...paper towels and plastic wrap...would be a good way to go, although I'd probably go a bit further and say to keep it in a warm place.

That said, why bother? This is a steel wheel that isn't really worth a whole lot of effort. Looking at your first picture, you already have an aluminum wheel in the frame, why not just use it? Aluminum has numerous advantages as a wheel material over steel. The first is weight and the second (and more important) is that it is a better braking surface, especially in wet conditions.

dsbrantjr

Although with all of the pitting and roughness that the rust removal will leave behind you will likely get excellent braking action, until the rough brake track surfaces quickly grind the pads away. I'd say the rim is a goner.

FBinNY 

I'm going to defer to cycommute on this if he responds, but I'd be concerned about dipping the rim or even wrapping it for acid treatment. You have dissimilar metals, ie the chrome plated steel rim, and brass nipples.

The acid will reverse the rust in the steel, but you'll end up with a surface that looks like a badly maintained road. There will be patches of chrome interrupted by patches of bare steel and the life of the finish will be short. The process may also speed separation of the chrome.

Then you have nickle plated brass nipples, and I don't know how they'll handle the treatment.

So, I don't think the job is worth the effort, and may cause new and different problems.

As I said, I'd like to have Cycommute confirm or correct my questions about the chemistry, since that's his area of expertise, but we both agree that even if all goes well, the results will be very disappointing.

Wilfred Laurier

My preferred solution to that problem:

ISO 630 27 inch - Harris Cyclery bicycle shop - West Newton, Massachusetts

nfmisso

Are the cups in the hubs good? If not, you have scrap metal at best.

If the cups in the hubs are good, then the hubs are salvageable.

Put an old tire on the rim, and cut the spokes. The recycle center will take the rim and spoke remains.

Get a polished Sun CR18 rim, stainless steel double butted spokes, and build a new wheel; as Wilfred suggests.

cyccommute 

There are a lot of steel wheels out there with textured surfaces. They don't stop any better than nontextured ones.

Looking at the picture again, corrosion of dissimilar metals is a moot point. The white color of the spokes in the second photo is a dead giveaway. The damage has already been done.

Oxalic acid doesn't "reverse" corrosion. It's just particularly good at dissolving the iron oxide. The oxalic chelates the oxidized iron and allows it to wash away. Hydrochloric acid will was away iron oxides as well but it does so by reacting with the iron ions in a different mechanism. The surface is going to be pitted no matter since, like the dissimilar metals, the damage is has already been done. The oxalic probably won't harm the plating in either the rim or the nipples (likely different types of plating) but it won't do the brass in the nipples any good.

But, overall, the rims and spokes appear to be in pretty bad shape. They aren't anything special and putting a lot of time, effort or money in to salvaging them just isn't worth it.

FBinNY 

You and I agree that the wheel is toast. Obviously reverse was a poor choice of words, but I only meant cosmetically, since rusting steel is like ringing a bell, it can't be undone.

But you sidestepped the one point where I was hoping you could offer an expert opinion. Specifically what, if anything, happens to nickle plated brass in oxalic acid, and does it make a difference if it's in contact with steel at the time?

fietsbob

So, when an aluminum rim offers so much better braking the reason covet the steel rims are What?

Adam65

When I saw this bike for the first time, my first thought was "that rear wheel is probably lost". Than I tried to find new 650B rear wheel on Ebay and there was no any. Only disc specific and crazy prices.
Front alu wheel cleaned very well, just lot of elbow grease. Than...not much choice-I tried couple metal cleaners, metal polishers which I have in garage, scotchbrite etc...wasted time. Oxalic acid only was lesson I took. The plan is to clean rest of the bike best I can, rear wheel-let oxalic friend do best it can and get the bike on the roads-try it-feel it-find out if I love it and if I want to use it and invest on it.
And oxalic acid buys me some time to find out all that and to make my decisions.
I have huge sympathy for this crazy bar, crazy wheelbase (1115mm !), crazy rake and wonderful Suntour shifters. Current steel wheel is temporarily, I know that and that is why I am not concerned about some possible "side effects" of using acid. For same reason-I decided not to strip the wheel down etc.
I need loaded touring type, heavy duty 650B wheel-where can I find one ?

fietsbob

Id get a Rim and have the wheels Rebuilt . have any Bike shops where you live?. QBP sells to Bike shops , many have an account..

Its not so uncommon a rim these days ..

many Wholesalers have a few people using the parts they sell to build a wheel and then ship it to dealers . it's a pretty good deal .

cyccommute 

Oxalic chelates lots of metals. It won't harm the copper in the brass but it will go after the zinc. I can't say much to the relative rates but I suspect that zinc is a more reactive to than the steel is. The nickel plating should be relatively inert so the nipple would probably hollow out from the inside.

FBinNY 

Thanks, that was my concern.

cyccommute 

QBP has a rear one with an LX hub and Velocity Synergy rim that retails around $175. The front sells for $150. Both are 32 hole which is a little light for touring. Velo Orange sells a beautiful set of 36 hole 650B wheels with Grand Cru hubs for $170 front, $255 rear. Or you can build your own with either a Velocity rim or the Velo Orange Diagonale rim. The Diagonale is about $65 and the Velocity is around $100 per rim.

Amesja

If you want to try and save the wheel without disassembling it you can always go to a big-box store and buy a Rubbermaid 20-gallon storage container, or the generic equivalent which is usually well under $10. These allow you to drop the whole wheel in and you can add the level up right under the hub. 3 turns of the wheel will get the entire rim. I've done this to quite a few old Raleigh 3-speed wheels and the results are usually very good. You don't need the OA to be super strong. Even a couple of tablespoons in 5-10 gallons of it will do the trick over 8-10 hours if you are SURE to degrease the rust beforehand. That's the trick. Brushing with a brass brush mid-soak helps too. .

It's not going to reverse the damage that has been done, but the rim is going to look much better than it did. If you attack it with a fine brass cup brush in a dremel tool once you are done and have it dry, the steel in the pits where the chrome has been damaged will shine right up and take on a brassy hue from the residue left behind from the brass brush. From 5-10 feet you can't really even see the damage. It's best to put some sort of wax on the rim or not take it outside in the wet if you don't want it to rust right away again.

It all depends on what you want to do with it, but it is pretty amazing how well OA works on some old crusty rusty item, especially chrome that has been pitted. Often the pits are smaller than you thought once you get the rust "growing" out of them converted and out of there. It often looks much worse than it really is when you are looking at the raw bloom of rust "growing" out of the pits. The transformation can be very striking. A seen and posted a few before and after pictures here that look almost like they were faked. Having brought back stuff that almost looked like it sat at the bottom of the ocean myself, I know what is possible.

But it is still pitted, and if you look closely it's not the mirror-smooth finish it came with. But when everything is all silver and shiny with the rust all gone, it's 10,000x better.

Gresp15C

That rim looks too far along to restore -- the chrome is long gone.

I grew up with steel rims. When I was a kid, we'd clean the rust off our Schwinn rims and handlebars with Brillo. It would last until the next winter. But it was always just light surface rust, and the chrome was still intact after we cleaned them. This was probably the result of low quality chrome plating.

One thing I remember was, we all thought that the rust would help with braking. It didn't.

Amesja

That rim is nothing. That's just surface oxidation and some pitting. I've brought back much worse. The wheel itself, the spokes and the nipples are probably more suspect in the long run though. If/when it comes out of true it'll probably take replacing a good number of nipples to get it back into shape.

Rubato

What happens w/oxalic acid and aluminum? I have an old set of Campy brakes (aluminum) with steel quick release levers that are rusted. I'd like to clean them up but taking out the rivets seems risky....

cyccommute 

It shouldn't be too much of a problem. Aluminum is more reactive with bases than with acids...especially organic acids like oxalic.