Hi all,

Purchased an 853 Reynolds Steel road bike and noticed minor surface rust inside the seat tube, LBS recommended to use "Dirt Juice" degreaser to try and clean the rust, but now I'm not sure about whether I should rinse the seat tube, as there is mixed info between the need to do so and the threat of water on steel leading to further corrosion...

In short is it essential I rinse the non-solvent degreaser from the inside of the seat tube.

Any help/advice would be greatly appreciated.

Stevr:

If you haven't put chemicals down inside the frame, don't. A little rust coating isn't an issue and I use a corrosion preventive lube to spray. If the rust is scaly, then you've got structural issues with corroded metal and I would try and source some round metal wire brushes and put the shaft into the tube to clean it out a little to get a better idea of how bad the rust really is. Hopefully, you haven't put chemicals down the tube, yet.

But if you did put degreaser down, I would give the inside tubes a very good rinse, with bottom bracket removed, and frame stripped. And while at it, if you can get try and aim water into the chain stays and other tubes, or put the entire stripped frame into a tube of very clean water, dump, and the repeat. And if it's sunny and hot out, I really recommend you leave it out in the heat to bake bone dry. Then I'd spray an anti-corrosive lube (corrosionX, perhaps) to coat the metal on the inside. Wipe drips and excess pools of lube.

The problem isn't the degreaser being there for a short time, but the residue left and what it may do to corrode steel during wet months when moisture can get inside the frame and re-activate any chemical reactions that slowly dissolve joints and welds. A metal impregnated with a lube will help repel water.

Get and use some ACF50

Thanks for the reply, unfortunately I had used degreaser, though only approximately 10ml. I will return to the LBS tomorrow and ask them to assess.

So many things wrong...where to start

-A corrosion preventative is a chemical, too.

-Degreaser residue isn't going to dissolve joints and welds - at least not on a human time scale.

-Metal isn't impregnated with lubricant.

Stevr: Degreaser does nothing for rust. Water based degreaser removes hydrocarbon materials, i.e. oils, in the same way that detergent removes it from your clothes. It basically encapsulates the oil and allows the oil to be washed away with water. That's not something that water and oil usually do.

Used on rust, however, all a water based degreasers do is put water in contact with steel and promote further rust. Something you are probably finding out.

gyozadude's second paragraph is good advice...partly. Strip the frame - check. Rinse the degreaser out - check. What he missed - or didn't know - is to remove the water that you used to rinse the degreaser. This is best done by chasing the water with something that dissolves the water but evaporates quickly. Acetone or denatured alcohol does a very nice job and evaporates quickly. Use either in a well ventilated area (outside works nicely) and then let the frame bake out in the sun.

Before you reassemble the bike, you can treat it with a corrosion inhibitor if you like.

The only thing I'd like to add to cycommute's excellent appraisal and recomendations is to definetly use a corrosion inhibitor at the end of all this. The use of the water based degreaser and the subsequent rinses will have stripped any protection that was in there and the frame will tend to rust more quickly. So you want to use a good film style protector to coat the metal and resist any future rusting. The stuff sold as "frame saver" would work or you can make up your own witch's brew.

The last frame I did I used some Maxima motorcycle chain wax. This stuff goes on thin and dries to a sticky waxy and slightly greasy film that stays in place. To get it to move around and coat the frame I shot about an ounce and a half into a jar and added a similar amount of Brake Klean spray solvent. I chose Brake Klean as my solvent to allow spreading out the chain wax because it's known to evaporate quite fast but not TOO fast and at the same time it doesn't affect any paint finish that I've found so far. But a small spot check on the bottom bracket to be sure isn't a bad idea.

This mixture, or any frame saver coating, is then poured in and the frame tipped around to slosh the mix over all the inside surfaces of the top and down tubes and both sets of stays. The seat stays required me to suck some of the mixture up in a little squeeze bottle and inject it into the breather holes then slosh around and pour out the excess through the same holes. The seat tube and steering head tube where swabbed with a patch of paper towel soaked in the mixture to ensure a good coating.

Of course this resulted in a horid sticky mess over the outside of the bike. But that cleaned up easily with a bit of mineral spirits and some paper towels. The frame was then left for a couple of days to "dry" away the brake cleaner solvent before adding any parts which sealed up the frame.

And I sure would not trust that shop guy again for any advice on such things. He may be OK for wrenching but his knowledge of solvents, rust and related stuff is lacking.

EDIT- just to add a note that none of this will remove the slight rust film you have now. But it will stop and prevent any future rusting so what is there won't get any worse.

Thanks BCRider and Cycommute. Would Fish Oil act as a suitable preventative? Furthermore (I seem to be doing this all wrong) it's the height of winter where I am, what would be a good alternative for drying the frame that isn't going to introduce any extreme negative conditions. Leave it stripped in a small room with a dehumidifier? Or is heat key?

Fish oil, if it's what I think it is, will go rancid over time and stink to high heaven eventually. That and you'll have flocks of cats following you everywhere Stick with something related to dead dinosaurs.

If your solution uses any solvents you want to dry away moving air is the key with some warmth being fairly important but secondary. A hair dryer set up to blow through the tubes would do the job in an hour or less. Start by drying out the seat tube and BB shell. Then cap off the openings to force the warm hair dryer air through the down and top tubes and chain stays assuming they have holes into the BB shell. Run the dryer on "low heat" so it doesn't over heat from an hour or so of use. For the seat stays don't worry about them. The vent holes will eventually allow them to dry out. The main thing is to dry out the main triangle so you can get on with building up the bike.

Perfect, thank you for all your help

Chemicals with ions that have potential to oxidize iron are a concern, and those in many degreasers will do so in the presence of water as the solution agent. As for oil wetting and penetrating metal, actually it does. It depends on the type of oil and surface of the metal. The inside of most metal frames is bare, and many types of corrosion inhibiting sprays will spread and penetrate and displace water. I service not only bikes but lots of saltwater fishing reels too. So it's no secret how we protect against corrosion. As for "human time scales," again, you're making judgements without understanding stress corrosion/cracking processes. Stress at matel joints can change polycrystalline properties making more smaller boundaries between crystals. More boundaries means more surfaces to attack. Stress joints can wear out and corrode, especially when moisture is present (hence during the winter months). And that can be a LOT.

The process is emulsification. Yes, but it does so by ionization. If the potential is sufficient to oxidize iron, you have problems. Note that no all corrosion of iron results in brown rust. Iron may enter solution and erode. Why take that risk? It really depends on the type of detergent. But most are alkali. Ever stick a sushi knife in soapy water for too long?

The water causes rust not because of it's properties, but because it is a solution for transport of ions. And adding some off-Ph detergent increases the rate of transfer and builds a potential well above and beyond water. Certain types of fluids displace water. That's what you want to coat the metal with. Because moisture will get into the frame. You want to prevent what ion transport will do to the iron. It's basic chemistry.

So having flocks of velociraptors following you everywhere is better?

KeS

It's a myth that metals such as steel absorb oil. The only way for oil to be absorbed into a metal is for if the metal was formed in a manner that it is somehow porous such as in a bad casting or when deliberatly done for oil or grease retention such as in sintered bronze bushings.

At the very most the surface finish of the metal with steel tubing is of some measure of roughness which promotes lubricant retention due merely to surface tension forming a meniscus between the peaks in the surface roughness. But that's hardly the same thing as "absorbing" any oil or grease.

The myth is that zero oil will be absorbed. I agree, the surface is porous. A porous surface absorbs some amount of wet lubricant and it coats and spreads. The absorption, though on the surface, creates a wetted-wall that forms a barrier to water and air that slows down oxidation of steel. And guess where the porosity is highest? Where the rust has eaten into the steel, which is often where the stresses cause work hardening and micro-fractures. Hence, even more important to spray something that penetrates, coats, and is absorbed into cracks and crevices which displaces potential water from getting in there.

I think we're getting hung up on "absorption." We shouldn't. Absorption of photons on skin is less than 500microns. Absorption of alpha particles less than 100 microns. These are surface depositions. But they are all "absorbed" and not likely to be displaced once there. Experiment: spray some WD-40 on some cast iron satin surface. Note how it spreads and is absorbed into the surface and changes the surface colour. Now spray and wipe with water. Stain still there? Yepp. Looks like the lube got "absorbed." The inside of most metal tubing is not finished or being exposed to some mechanical force that threatens to displace the surface constantly (e.g. a bearing). Spraying a lube designed to prevent corrosion will coat the surface and penetrate that surface as well as displace water. And that's what we want.

If a water based degreaser had a heavy load of ions that could oxidize steel, I'd almost agree. In water based degreasers, however, the load of ions in quite low and they aren't iron oxidizing or iron scavenging ions. The ionic component of most water based degreasers are things like sodium citrate and sodium nitrate. Some may use sodium hydroxide but steel can stand sodium hydroxide up to 20% without problems.

Water based degreasers do not, however, use ions like chloride which will cause the kinds of corrosion you see with salt water equipment.

Rust inhibitors work by reacting with the surface layer to passivate it. This usually means sacrificing a small layer of the steel to form an insoluble oxide complex. Aluminum does that naturally with air.

You can put a layer of oil down on the surface of metals. It may penetrate to the crystalite edges of the metal but only to a very small degree. It will not be absorbed in to the main body of the metal crystalites at all. It's a polar/nonpolar thing.



The process is a special kind of emulsification using surfactants. Surfactants can be ionic or non-ionic. Some are alkaline which means have a pH above 7. But they don't ionize anything. Surfactants form micelles...small soap bubbles. They work like a herd of muskox. They turn their oil friendly tails inward and take the nonpolar greases inside and point their water loving horns outward.

I would never use a water based degreaser of any kind. There are other, better degreasers. But the reason I wouldn't use them is the water involved, not anything else.


Water does form rust because of its properties. Water absorbs oxygen from the air quite readily. It also set up potential differences between crystalites in the metal so that you can have oxidation occur at the edges of the crystalites. It's basic electrochemistry

Here's the situation:

a) OP has put some degreaser down into his bike at the recommendation of someone at an LBS. We agree that might not have been the best course of action, but what's done is done.

b) we don't know what kind of degreaser, and what the properties of that degreaser are, and I think we're in agreement that it would be a good idea to flush and dry the frame in and out.

c) we seem to have all sorts of definitions for absorption or non-absorption, and want to relabel chemistry as being "electro" chemistry (a subset). Surely, you are correct. But I'm not sure if it adds value. I could go into a treatise on whether dissolved oxygen is the source of rust or dissolved CO2 that forms carbonic acid in water that has higher electro-potential for rust than free oxygen. The main point is that we want to prevent moisture (which inevitably gets into a working bicycle) from causing more corrosion. Regardless, regular maintenance and coating with an anti-corrosion lube spray (not some commercial coating technology that sacrifices some surface of the metal to form a barrier), will reduce or inhibit moisture penetration into the surface of the metal. The amount absorbed may be superficial. But does it last a while and inhibit rust? Yes or No? Results for most folks is yes.

Is the problem solved for the OP? I think so, unless you folks just want to dive into which electrolytes cause more rust and which reactions have greater potential (or lower potential depending on your reference point). We can all grow bigger brains. But in the end, if you coat the metal with a barrier (spray lube or something else) and it inhibits water penetration, this will inhibit rust.

The brand was Juice Lubes "Dirt Juice - Super Gnarl". I've looked for the contents and tried contacting the brand, but no dice as yet.

Ha, you guys lost me at post #10 as I really am a newbie, though I very much appreciate and effort you've taken to respond. I've contacted someone local who builds and renovates steel frames who will bead blast the tubing to dry it out. I'm hoping this will be the best solution.

I can't find the COSHH on Dirt Lube products either. I would suspect that the degreaser is similar to most other degreasers which are mixtures of Butoxyethanol, surfactants and some salts. Degreasers works to remove grease but they don't remove metal...too much. Soak them for a very long time...we are talking months...and they might cause a problem. The amount of degreaser you've used - about 10 ml - isn't enough to fret too much about. The salts in the degreaser aren't there in high concentration, they aren't particularly hygroscopic and don't have much affinity for steel. If they are left there, I doubt that you'd see any problem. They certainly aren't going to dissolve the joints or welds. A saline solution - 7% sodium chloride - would take years to cause that kind of damage and these salts have orders of magnitude less affinity for steel.

Part of the reason that you rinse degreaser off is because you want to remove the grease. Think of it like washing dishes. You could just apply the surfactant - fancy name for soap-, wipe it around and let it dry. But that doesn't get the stuff off the plates. Same with degreasers. The grease just sits there on the chain and isn't removed.

The problem is that, like your plates, after you rinse the degreaser off, you want to dry the parts before you put them away. With bikes that's a problem because you can't get into the nooks and crannies where the water wants to hide. That's why I suggested chasing the water rinse with something that dissolves the water and dries quickly. Denatured alcohol or acetone does a dandy job. You could even chase the degreaser in your seat tube with some water, rinse with alcohol or acetone and let it dry on the - let's see you said it's winter now so I'm guessing the sun is to the north - north side of the house in the sun. If the bike is relatively new and has cartridge bearings you can probably do it without taking anything apart.

Use a scotchbrite pad on the rust spot by wrapping it around a dowel so you can use it to scrub at the spot inside the seat tube. Then cover the new shiny metal with grease. Grease your seatpost too.

In the future, I'd suggest using mineral spirits - aka naphtha, white gas, benzine (NOT benzene ) - to do all your degreasing of moving parts. Fewer steps, less volume, and less hassle.

Now you're overthinking the issue. And I'm not sure what he's going to do with bead blasting as it won't reach in and clean out the degreaser residue. It would remove the slight rust film you found but that isn't a big deal. The rust isn't going to harm anything once you coat the inside of the frame with a rust resistant film. And besides a bead blasting treatment won't reach that far into the frame. And it won't get into the top or down tubes at all.

Looking up the Dirt Juice it's apparently a detergent style degreaser. That means you want to rinse out the frame well with some water. Use a hose to liberally flush out the tubes that you used this stuff in. Be sure that you get the stream to direct into the top and bottom tubes to flush those out as well. I'm assuming that the frame is stripped down completely here. If not then because you used this stuff at all in the frame you'll need to strip it down now to do a proper job of cleaning the detergent out, drying the frame and finally getting the insides coated with a rust resisting product.

You can dry out the insides pretty quickly with a hair dryer. Set it up to blow into one side of the bottom bracket shell and cap off the other side. This will blow air up the seat tube and dry it quickly. As the seat tube and BB shell become totally dry cap off the end of the seat tube so it forces more of the air through the down and top tube and out the chain stays. Doing things this way should result in a totally dry insides in about two hours. At that point you can take on the rather messy job of coating the insides of all the tubes.

To do that you will need to pour in some of the frame saver or whatever mixture you choose and slosh it around by rolling the frame so the inside of all the tubes are coated. Then pour out the excess and use it on the next tube. Repeat until you're sure the down and top tubes and the chain stays are fully coated and then use a wad of paper towel and a stick soaked in the mix to push down the seat tube to coat it and through the steering head tube and BB shell to coat them as well.

So all you need to do is

1. Flush out the frame well with a hose.
2. Dry the frame out with a hair dryer.
3. Coat the insides of all the tubes with "Frame Saver" or some mixture that leaves a thin greasy protective film in ALL the tubes.