Rust!!!

Morning all,

I have been thinking (as i do) about rust - some may call it patina but, really, i do not like it or what it can do.

Strangely, i do not know a lot about rust - it is oxidized iron or steel (i suppose) and it weakens metal. It spreads in the right conditions.

So my odd questions are -

1. Is rust completely preventable?
2. What is the best way to prevent it?
3. Do wet conditions make rust worse or are there other factors? I know that sea water corrodes but would steel left in distilled water corrode?

Any other rust related info is apprecaited.

Odd questions perhaps, but rust is a bike killer and i don't see much info on RB in relation to it. Answers may be for the greater good.

Have a great weekend everyone,

Richard

Morning Richard

Whats that old saying, rust never sleeps?

I agree with you, unslightly rust chips and spots they should never be passed off as patina. I think of 'patina' as aged paint that has developed a different type of gloss to its finish. Its hard to explain but it does have a certain look. It may include a few marks or wear and tear but not rust.

Having said all that I've had possibly 100-150 bikes pass through my hands from the early 50s to the late 90s. I've only had one bike that had rotted out at the bottom of the seat tube. So even rusty wrecks will sandblast back to clean bare metal.

I think keeping a bike clean and waxed is the best prevention and drying your bike off if you've been out in the wet. Also dry storage (in the house ) makes a big difference.

For the inside, unpainted surfaces of a frame, a coating of linseed oil is apparently quite good - it's what the Czech builders (Fort) of my CX frame used.

David

Rust is simply the reaction between iron (which is in steel) and oxygen and will always happen because of the electrochemical series. In dry air it happens very slowly so aircraft are stored in dry deset conditions (aircraft boneyards) and is accellerated in the presence of moisture and other electrolytes such as saltwater. Iron rusts slowly in distilled water. Rust unfortunately falls off the surface and doesn't for a passive layer.

In theory it cannot be prevented (like heat death of the universe) but can be slowed down to a crawl by covering with grease / paint etc and keeping it dry...

Shaun

Midlife":11uix1q7 said:

Rust unfortunately falls off the surface and doesn't for a passive layer.

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Which is unfortunate. In contrast, for titanium frames the oxide layer that forms on the surface actually helps to protect it (also it "self-heals" in the event of a scratch or scrape as the exposed metal soon oxidises).

David

Midlife":39b6a15h said:

(like heat death of the universe)

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Something that certain Lancastrian physics professors like to keep telling us about on the TV. So much for "things can only get better", eh Brian?

David

Amen to the above, rust is much more of a problem with old cars than bikes for the following reasons:

• Sheet metal is substantially thinner
  It is formed into complex shapes that serve as moisture traps
  It is often made of low grade recycled material (impurities accelerate oxidation)
  It is usually stored outside for the duration of the vehicle's life

Applying a wax/oil based film to unpainted areas prevents moisture and air from coming into contact with the steel. Waxoil and Dinotrol are two well respected products, which I believe were originally developed to preserve oil rigs in the North Sea from salt water corrosion. I have also known people to use old oil and diesel mixtures to good effect too.

Definitely not something worth loosing sleep over with a push bike though.

How would you treat rust on this frame?

ed_de_ball":11hj5xxr said:

How would you treat rust on this frame?

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A lot depends on how good a paint match you can get and how 'perfect' you want it, or how much you want to keep its originality. For 'perfection' you'd really need to look at respraying but a good job will cost £120-£200.

Personally, I think original paint it worth keeping if at all possible. If you have a dremel with the mini sanding discs they are great for cleaning up rust spots back to bare metal. Then I'd use a rust inhibiting primer with a fine artists brush, then the colour. A light rub with 1200 wet and dry will take care of any brush marks, although a good brush shouldn't leave much. Followed by a T.Cut and wax, if you've got a good colour match it will be invisible from a couple of feet. Some colour's are much easier than others, black is probably easiest. I think yours falls into the more difficult category! Ray Dobbins gives some general ideas on his site:

http://www.raydobbins.com/pantografata/ ... ouchup.htm

Just a point which hopefully may be my eyes or an optical illusion on the photo, but does the crossbar have a slight bend in it towards the front?

Thanks for all the responses - i did learn something - that rust is a result of a reaction with air - i had thought that there had to be a contributing factor or catylist. I am glad i asked the question now.

So now i know that storage of items in a vacuum is the only solution and other cures will only be inhibitors, very interesting.

My query originated when i looked at my Gazelle A frame which is in similar (maybe worse) condition to Ed_de_balls and i received exactly the same advice that Robbie has given.

Hope the sun is out where you are,

Richard