removing stain from stainless

I hope we are all aware of the problems mixing chemicals can have such as giving of toxic gases. We had a very unfortunate accident at our school from someone mixing water into Sulphuric Acid which reacts violenty, but pouring Sulphuric acid into water is OK.
I do not like chemicals...

 

Ok, weekend update, I have now tested "the works" toilet bowl cleaner, baking soda, muriatic acid and molasses, coca cola and re tested the spotless stainless product. So far we can eliminate coke and molasses from contention as neither of them had any effect whatsoever, nada. The coke was original formula and didn't even take the tarnish off some old pennies and the molasses mixed at 9 parts water to 1 part molasses and soaked for 24 hours also shows no effect at all. Of course the muriatic acid worked very well at a 2:1 dilution, removing all stains in just 5 minutes of soak, however its nasty stuff but I will continue experimenting with a longer soak with a weaker solution and see how that goes. The baking soda works well as a scrub and it actually worked as a soak if you give it some hours but is not practical as it doesn't dissolve and stay in suspension and just settled in the bottom as the water cooled down so I would reserve it as an economical mild scrub. I have just done a side by side test of the toilet bowl cleaner ($ 1.88/quart) vs the commercial "Spotless Stainless" product at about $ 32.00/quart with shipping i think. In my previous tests of the spotless product it didn't work at all so this time i washed the part with dish soap, rinsed and dried it off and it did work. It is a gel type product and you brush it on, wait 30 minutes and rinse and it worked as advertised, however, the toilet bowl cleaner (The Works) is a pleasant smelling liquid which i just soaked an identical turnbuckle toggle in for the same 30 minutes then rinsed off and it came out a little cleaner and the liquid is still available for reuse, both did require a little scrub in the same spot but the works was the hands down winner being easier to use, reusable and many, many times less expensive.
CDK, I have not discounted the ascorbic acid, i just have not been able to find it locally in an economical form, i have however found it online in bulk powder form for a good price so will order some as well as some citric acid and test them and report the results.
My goal is of course to come up with something where i can mix up gallons of solution to soak my shrouds in to clean them with minimal work. Scrubbing is not an option, it has to be simple as well as economical for the quantity i need. While the muriatic acid works well as im sure many other acids such as nitric, phosphoric, oxalic etc would they are nasty, dangerous chemicals which i would prefer not to use but will if nothing else works out. The toilet bowl cleaner would certainly be a good contender but i still want to test the vitamin c and citric acid now just to add to my knowledge base. Point taken Tom re the acid into water, i did know that having worked in the chrome plating industry many years ago but others may not so thanks for pointing that ou

Steve.

 

What preparation (e.g. concentration) of citric acid for passivation?
Where does one buy citric acid?
What conditions?

 

24 hours isn't a test of the molasses. As I pointed out earlier, it's a slow soak, The molasses needs to ferment with the iron. It's th fermentation process deoxidizes the rust. To ferment may require a week or two of soaking in molasses water. It does work if you are patient.

 

Could embrittlement be an issue if you are planning to acid clean shrouds or rigging components? An acid bath doesn't sound like a good idea to me with something like muriatic acid. CDK what is your take on this?

I regularly use a mixture of phosphoric acid and soap for metal cleaning, it is very mild (I don't wear gloves to put it on), it is quite slow acting but effective. It also cleans 'tea' stain off frp hulls and turns grey teak brown again with very little scrubbing. It needs to be washed off after as it leaves a white residue (phosphate?). It is particularly effective for removing the brown spot stains where steel grinding dust has blown over other boats.

I'm interested to try vitamin C as a cleaner...thanks CDK

 

Lots of options, but as I recall, I found citric acid at a beer brewing supply company, mixed it to 10% by weight and then soaked it for 20 min at 150F. But 2 hours at room temp should also work.

Some people use CitriSurf.

 

I would like the answers to the same questions. Its easy to find in bulk online in powder form.

 

Ok, you didn't elaborate on what a slow soak meant. When products like the toilet bowl cleaner soak for 30 minutes and the acids 5 minutes, 24hrs seemed like a long soak to me but now ill give it another try, thanks.

Steve.

 

I agree, while the harsh acids do work well the whole object of this thread is to find a more mild alternative that actually works and is cost effective for the larger batch necessary to soak 12 shrouds. While I have no problem using something harsh on items like toggles, clevis pins etc I really don't want it down in my swage fittings or the inside of the cables. I am ordering some ascorbic and citric acid in powder form online to try out.

Steve.

 

I forgot to ask, where does one buy phosphoric acid?

Steve.

 

product called phospho in paint stores another called chemprime, another Ospho. Sold as pre-primers

 

never tried it, but a little brewers yeast added to molasses water might speed he fermentation process.

 

Thanks, i guess making the molasses/water more concentrated wouldn't help, really just patience. I will give it another try at a later date as im running out of small parts to clean before I settle on something and move on to the standing rigging. To be honest im totally impressed by the toilet bowl cleaner, it works quickly, does not give off nasty fumes and is cheap enough to buy gallons of it so would do the job but I still want to check out the ascorbic and citric acids first.

Steve.

 

takes a while to ferment, but if the toilet cleaner gets the job done faster? I'll start using it too!

 

I'm not looking to pee in anyone's cornflakes here, but... I'm driven to play Devil's Advocate on this one.

Am I alone in being concerned with the concept of purposely soaking one's standing rigging in a corrosive solution (possibly for an extended period)? The same rigging which holds up a $10k-$20k spar, in addition to a few thousand $ in wiring and running rigging. Plus a rather expensive amount of $ in sails.

I can't see it taking that long to stretch out each stay, & shine'em up using a polishing compound, and or possibly a 3m greenie pad.
Admittedly such wouldn't remove the rust from the inner parts of the wire, but if they're that heavily corroded, it's time to replace'em anyway. Particularly as, barring cutting a few of the shrouds in question into sections, you can't really tell what the condition of the wire truly is.

And if in doubt on any of this, & or looking for solid answers, it's easy enough to ring up a couple of rig shops. Or better yet, stop by and let them examine the stays, & let'em give you some expert feedback.

I mean, realistically, rigging wire's not that expensive. And putting on your own end fitting's is far from rocket science, in addition to a good skill to have. Plus, you can keep the old stays around as an "insurance policy". So....