Slow & Easy Stainless Cleaning

[bad.wabbit]

SfSailing ~ since you are in my hood... The least amount of elbow grease fire me has been to take them to Scientific Platers Inc (http://scientificplaters.com/) in Oakland. They will electropolish them, which converts the surface to a much higher chrome content and prevents future corrosion. They don't mechanically polish, so scratches and pits will be diminished but still visible.

[thinwater]

ASTM list 5 general methods:


1. Citric 1: 4-10 w% Citric Acid, 140-160F, 4 minutes minimum
2. Citric 2: 4-10 w% Citric Acid, 120-140F, 10 minutes minimum
3. Citric 3: 4-10 w% Citric Acid, 70-120F, 20 minutes minimum. (This is the basis of the commercial products we are testing in this review.)
4. Citric 4: Other combinations of temperature time and concentration of citric acid with or without chemicals to enhance cleaning, accelerants or inhibitors capable of producing parts that pass the specified test requirements.
5. Citric 5: Other combinations of temperature time and concentration of citric acid with or without chemicals to enhance cleaning, accelerants or inhibitors capable of producing parts that pass the specified test requirements. Immersion bath to be controlled at pH of 1.8-2.2.


There are also nitric acid methods. No other acids are mentioned. AMS 2700 has a similar list.


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Basically, you can use either Spotless Stainless or Citrisurf if you want a thickened product, or you can buy generic citric acid cheaply.


The easiest method, if the parts are off the boat, is a long soak in warm 5% citric (stronger does not help). If you do it on the boat, wait until warm weather (it does not work nearly as well if cold).


Unlike just polishing, passivating slows the return by leaching iron from the subsurface.

[Shrew]

One thing I would be concerned with is, WHERE is it staining?? Or more accurately WHY is it staining?

Are the stanchions made from 316L (A4) stainless or a lower grade, such as 304? If 304, I would replace the stanchions. Even 316 isn't as good as 316L (A4).

Stainless steel rusts in the absence of air. Is the staining occurring mostly around the mounting flanges at the base? Or if not welded, where the tubing and connectors are fastened? This would indicate that the fasteners themselves either have water ingress, or are also not 316L.

If the fasteners are rusting, then they should be replaced with 316L fasteners and the stanchions would need to be re-bedded.

[beirutsailor]

I am a cheapskate live aboard an go whenever possible for the generic/household alternatives to the chandler's offerings. But with a boat from 1978, I achieve "like new" stainless tubes with StarBrite Stainless Steel Polish. It takes only a drop for a lengthy bit of tube and protects for a month or more. One bottle lasts a year.

[EmeraldCoastSailor]

I second Barkeeper's Friend but did I read it can be used on teak?

[thinwater]

I wonder why industry, the military, ASTM, and ASM have all standardized on either citric or nitric acid, and all on citric acid when safety and ease of use matter? Probably because they have tried everything else and citric acid works better. There are also mil and industry tests suggesting there is very nearly no difference between citric and nitric.



Just sayin'. You can work harder or try citric acid.

[sail sfbay]

The OP and forum might this article entitled "CLEANING AND DESCALING STAINLESS STEELS from the Nickel Institute helpful, particularly page 24 on passivation which discusses the role of nitric acid. Having said that I use Citrisuft which uses citric acid.

CitriSurf® 2310 | Stellar Solutions - Stainless Steel Passivation

https://nickelinstitute.org/media/46...gdescaling.pdf

[Clivevon]

You [I]clean /I] your stainless steel? I thought the point of stainless steel is that it is (pretty well) stainless?

If it is marine grade (a4, 316, 18/8/3 or whatever you want to call it) it shouldnt be rusting.

Over 50 years ago we talked about 18/8 stainless steel (18% chrome, 8% nickel) & 18/8/3 (with 3% molybdenum) was called acid resisting stainless steel. I left that world decades ago & coming back to it as a boat owner I learned instead about A2 & A4 stainless, or 304 vs 306. So things change - but 18/8/3, or A4 or 316 stainless steel (all same thing) on things like stanchions, pulpits, pushpits - should not be rusting. Mine are 40 years old. I've had the boat over 20 years & all I ever do is quickly hose them down with fresh water when I am washing the deck. They look fine.
Are you sure you have 18/8/3 stainless?

[Clivevon]

Sorry - should read 304 or 316, of course.

[tstano]

Maybe Schaefer Marine would renew them for you. I had several snatch blocks and other stainless items that I sent to them and they came back showroom bright. I have never had that sort of results no matter how long I polished. On the boat we have four citric cleaners as mentioned before as well as lemon juice for when I just do a walk by spray.

[Simi 60]

I'll worry about polishing s/s when I get paid staff onboard.

[Suricat46]

I usually get excellent, effortless and long lasting results by simple electrolysis.
Container: an old stainless steel pressure cooker linked to + positive
Rusty or stained parts: dipped in the bath from metal wires connected to - negative (Parts or wires shall not contact the container !)
Bath: sodium hydroxyde or sea salt solution (water)
Power: battery charger 6 or 12 V

Once all rust is gone (electropolishing), rince in clear water and don't forget to passivate all parts in acid bath .
Bon courage !

[tpierquet]

For years I have used a powdered cleaner call "Zud". It comes in a small cardboard cylindrical container. Wet the stain, sprinkle on the powder to make a thin paste, let it sit for a few minutes, and clean it off with a nylon scouring pad. works well to remove heat mark from welding stainless also. Also used it to remove rust stains on my fiberglass deck.

Your welcome...

[Happ]

One way to get the bits off is to buy a Demel. I bought a knock off of one for about $10 from Harbor Freight. A box of attachments is another $10. Amazon also sells them. I don’t use it often so these are fine. If you are a handy guy you will soon discover once you have one you will wonder why you never bought one before.

[JBP]

Hmm, I just use a scotch bright pad and fresh water. Gets rid of surface rust and they stay fine for a couple years.