A few people say the blue or white scubbies are less likely to scratch the stainless.
Yes, I have heard that… green scratches, blue is safe.
This is a good thread for newer brewers who might gain insight without having to repeat the shortcomings we have all gone through from time to time.
Craftmeister alkaline is the boss for cleaning and you can use it in repeated applications (I have a keg washer made out of a 6 gallon bucket with a submersible pump and rod with holes drilled into it to spray the inside of the keg or other vessel - I love it for my Kegmenter, too. I tend to rinse things to remove initial deposits of crud and let them accumulate in number for series cleaning of multiple vessels in one night). If you have some really stiff beerstone, the dairy product from the Farm & Fleet or equivalent is great as a soak (something like 3 ozs in 5 gallons soaked for a few days will literally allow wiping off the beerstone). I had no luck with Barkeepers’ Friend on beer stone - it is oxalic acid, but did not help for me in getting the oxalate off, even with a paste and significant scrubbing. I love it however in getting the bottom of the stainless boil kettle and the SS electric elements to shine. White or blue scrubbies or the dobie are what I use for wiping off sticky crud (never any steel wool or stainless scrubbies for the reasons stated).
I have heard that acid followed by alkaline or vice versa really clears off the beerstone quickly, so if time is a factor, those could be used in short succession, perhaps (I like to soak in the dairy product to allow the phosphoric to do its trick over a few days).
I really hope I didn’t damage the inside of the kegs where I used the steel wool. I didn’t need to apply much pressure as the water stains came off easily and what I used was the equivalent of an SOS pad but without the soap. Glad I mentioned it and glad you guys brought it to my attention. Cheers and thanks.
Well, I soaked with the beer stone remover for two additional days and the spots vanished. I went ahead and scrubbed the bottom with barkeepers friend just to be safe and re-pacify. Hopefully that will take care of the issue. I guess just longer soaking.
Hey, good news.
There is a lot of misinformation out there about passivating stainless steel. One of being that Bar Keepers Friend will passivate stainless. Even Palmer says it can be passivated with BKF. I used to believe that until I dug deeper into the subject.
BKF contains oxalic acid, which cannot passivate stainless steel. The problem has to do with free iron molecules on the surface of the stainless which prevents chromium from oxidizing, oxalic acid cannot remove this free iron. The layer of chromium oxide is what prevents the iron in the metal from reacting to oxygen and creating iron oxide. It may be possible to create a some passivating to occur naturally after scrubbing with BKF, but it it is not consider passivation by stainless steel manufacturers. Too much free iron is on the surface to create a good layer of chromium oxide.
The only accepted way is to bath the SS in either nitric or citric acid. Citric acid is the preferred acid because not only is it way safer, but it does a better job of creating a deeper layer of chromium oxide. Both acids will remove the free iron. After a soak in the acid solution, the SS needs to be dried and exposed to air for 24-48 hours. Citric acid is available at any place that sells canning supplies for fairly cheap.
i never had a problem with oxyclean free, never needed to try another cleaner but i’m sure the alkaline craftmeister is great but its 10-12 bucks for a lb and oxy is 8 bucks for 3 lbs. i guess its a good idea to keep a lb of craftmeister around for stubborn soils but oxy has never let me down and my fermenters/kegs are squeaky clean so i see no need to spend more money on CM alkaline wash but its all about preference . as long as your gear gets cleaned who cares how you got there
idk man, palmer is a metallurgist aka a metal scientist/engineer, if he says bkf will passivate ss i’m gonna have to believe him
Searching around the webs, I found this, which says Citric acid passivation was developed by Coors for their kegs.
Not to mention experience. I’ve used BKF to passivate SS several times and it’s never failed me.
I suppose there could be some variables at play as well. If you received a very clean [used] keg and your cleaning practices were good and you also happened to have soft water, your keg may stay in very good shape. Some of my kegs were purchased years ago when AIH was selling used ball-lock Cornelius kegs for $15. Some looked like they had been stored at the bottom of a lake. Yes, I cleaned them well but I also have high bicarbonate in my water and shower doors, faucets and the coffee maker all show signs of it. I am now 50% of the way through my kegs… filled one last night with boiling water and EasyClean and left it until this morning. A very light scrub with a green pad and it looks brand new now… sparkling clean and no buildup at all.
It may passivate, but there are varying degrees of passivation. Clean SS will have limited passivation on it’s own, but nitric and citric acids will provide the best protection. It’s not hard to look it up and discover this is true. If scrubbing and oxalic acid were to work, Coors wouldn’t have had to spend a bunch of money looking for an alternative to nitric acid. Not only is citric acid safer, it provides better protection from corrosion.
I have no doubt that’s true, but for my purposes BKF worked great. Took the rust off a poorly cut keg and it has not returned after 8 years.
No doubt Coors has a lot more invested in their brewhouse and it sees a lot more use than the typical homebrewer. While oxalic acid passivation may not be up to ASM standards, it is certainly good enough for most homebrewers.