controlling frame rust - pitting - is it possible

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hoogerbooger
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Joined: 14 Jun 2009, 11:27am
Location: In Wales

controlling frame rust - pitting - is it possible

Post by hoogerbooger »

I have an old 531 bike - that has extensive pitting on the upper face of tubes. From a respectful distance the paint and decals and early eighties parts look quite bearable to me. Vintage and lived with.

A proper respray and decals looks like £200 plus. I can't justify that spend really. At least not until I'm sure it's a keeper. Need to ride it for a year or two before I could get so attached to spend £200 on paint.

Is there anyway to treat & seal in rust/pitting to stop it spreading or at least slow it down ?
old fangled
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fausto99
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Joined: 19 Sep 2011, 10:06am
Location: NW Kent

Re: controlling frame rust - pitting - is it possible

Post by fausto99 »

A frequent wipe down with the proverbial oily rag? :D
Last edited by fausto99 on 24 Jul 2018, 10:15pm, edited 1 time in total.
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meic
Posts: 19355
Joined: 1 Feb 2007, 9:37pm
Location: Caerfyrddin (Carmarthen)

Re: controlling frame rust - pitting - is it possible

Post by meic »

Upper face pitting is probably caused by sweat, it certainly was in my case.
The big problem is that all those pits are full of something that will keep the corrosion going and unless that is killed off 100% it will just burst through any coatings, no matter how lovingly applied.

You can slow it down. Rinse it out the best you can and rub something into the pores of an oily, waxy nature. Waxoyl if you can stand the mess or frequent applications of WD40/GT85 oil type sprays.

Or you can strip of all the paint, rub off as much rust as you dare, treat repeatedly with phosphoric acid, etch, zinc prime, paint and seal, pray and wax polish frequently.

viewtopic.php?f=5&t=86807&hilit=holdsworth+rust

I "gave up" partway through and the frame sits, bare, on top of my wardrobe, it isnt rusting anymore though. :)
Yma o Hyd
hoogerbooger
Posts: 776
Joined: 14 Jun 2009, 11:27am
Location: In Wales

Re: controlling frame rust - pitting - is it possible

Post by hoogerbooger »

My head can't work out why it would carry on rusting if it's sealed in ( e.g. with wax or laquer) doesn't it need oxygen to rust ?......however I can see similar comment elsewhere that once it's pitted/ through the paint it'll somehow carry on rusting.

(I'm not keen on going down the strip and respray myself ).

the pitting is black so may have been treated. had been wondering if there was a way to clean it, treat the rust, dry it thoroughly and then laquer in.

But if that is pointless and slowing the process is the only sensible option ..then i've just been looking at stuff on solid lanolin as a wax. sounds like it may have a drier finish than waxoil and have rust inhibiting qualities..... so could perhaps make this his my regular "oily rag" to slow the process down.
old fangled
random37
Posts: 1952
Joined: 19 Sep 2008, 4:41pm

Re: controlling frame rust - pitting - is it possible

Post by random37 »

This is exactly what WD-40 was designed for.

I'd get it as clean as possible (ideally with steam), then keep spraying the stuff on. Little and often. It will "creep" everywhere, and leave a thin coating of oil behind.

If you think I am talking out of my hat, I would refer you to this:

http://cradpdf.drdc-rddc.gc.ca/PDFS/unc53/p526285.pdf

It did surprisingly well in that test. I know it's got bad press in cycle mechanic circles, but that is a comment about its suitability as a lubricant. It wasn't designed to do that.
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