So I did this today but now what?

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Slim M

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So I had on old AB keg I got from the scrap yard years ago but I thought why not turn into a fermenter. So I traced out a corny keg lid and cut it out on the sanke keg with a dremel. I could put the lid like I would have preferred because it got ribs so I offset it. If this works out I’m going to put some bolt on ball locks and dip tube for pressure transfers.

I filled the keg with a few gallons of water before removing the sanke center tube and put the lid on and left it in the sun and pulled the prv a few hours later and it held pressure so that’s good, but my problem is I got a little surface rust inside the keg. I’m aware bkf and elbow grease would take care of it but my arm is a little big to reach all the way around and the offset hatch makes it awkward. How would you go about scrubbing the inside? Thinking of making something like a giant flap disk from scrubbing pads I can chuck up in a drill and go to town with some water and bkf. Ideas please!
 

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That looks pretty awesome. If you can get your arm in there at all I would think any scrub brush on a stick would work (think toilet brush... but not toilet brush).

If there is rust in the keg you probably want to passivate it. I have seen posts on here multiple times on how to do that. It didn't sound too difficult.. Basically citric acid and warm water.
 
Yeah the rust is not very bad inside and bar keeper friend did the job on the outside. I’m just trying to figure out how to effectively get some scrubbing action going inside. Maybe a clean new toilet brush is the answer. Initially when I started I thought I was going to be able to have the opening centered an it would have made it easier but that didn’t work out.
 
An acid should remove (dissolve) the rust. Muriatic Acid (HCl) comes to mind. Cheap and cheerful.
Not sure what dilution to use, perhaps 2-5%? Just swirl it around. Or position the keg in a way that will leave it soak into the rust patches for a few hours or so.

Warning:
HCl is a strong acid and very dangerous even in skilled hands. It will eat through anything, given time, and is harmful to the body.
Use adequate protection, hands, face, eyes, body, when using it. Not kidding!

For comparison vinegar is 5% acid, but since it's a "weak acid," it only partially dissociates, doesn't have the free "protons" in solution as HCl has.

Now cleaning sanke kegs is always gonna be a chore. Especially after fermentations, with sticky krausen everywhere around the headspace. But using hot (homemade) PBW should allow you to clean it, without too much manual labor. Some sort of short pressure washer wand could make that easier, never tried myself.
 
Once I got the the center tube out I can maneuver better than I thought, so we’ll see how it goes with the bar keepers friend.

After I get the rust taken care of I think after fermentation cleaning should be to bad with some hot oxiclean or pbw. Honestly if it doesn’t work out I’m not too disappointed I’m out nothing but my time spent cutting the hole. But if it does work the idea of pressure transfer with a 10 gallon batch from a basically free ss fermenter is alluring. I was surprised I was able to get the latch opening close enough to right for it to seal up by cutting freehand with a rotary tool and small cutoff wheels.
 
Well so the old project keg has been filled to the top with 4 gallons of 5% vinegar and the rest water then capped and has been setting in the hot sun for 3 days. Tomorrow I will pour it all out, rinse, and do a bkf scrub with my makeshift brush then reevaluate.

Plan B will be to scratch the corny keg hatch idea and cut the opening out large enough to get better cleaning access and hopefully find a pot lid I can secure with a gasket to seal up.

Plan C is maybe I’ve got a 2nd kettle that I don’t really need, but I’m trying to make lemonade with my lemon’s. It was a real bummer to find the inside of keg was so nasty. I believe it’s salvageable for some purpose but not sure what yet.
 
Plan B won't work here. ;)
There's no way you can get a lid to seal.

If anything, a 6" or 8" Tri-Clamp would work, but would need to be welded or soldered on. And they're not cheap, neither is welding if you can't do it yourself or know someone.
 
The bonus of your corny lid is, you can stick a camera, or cell phone inside the keg for video inspections to make sure everything is as clean as you want it to be. It's just cleaning maintenance after that. Hot PBW, with a little Lye added if needed.

The pros use alkaline cleaner, probably with some caustic soda (lye) added, to clean. After a rinse cycle, sanitized with PerAcetic Acid. They have auto or semi-auto keg washers for that. We were staring at one of those keg washer carts in the craft brewery, where we had our grain buy. Makes a lot of sense to have one of those there.
 
Plan B won't work here. ;)
There's no way you can get a lid to seal.

If anything, a 6" or 8" Tri-Clamp would work, but would need to be welded or soldered on. And they're not cheap, neither is welding if you can't do it yourself or know someone.
This was the plan b I was thinking about.
1657297981021.jpeg
 
@Slim M did you finally get that keg cleaned up?
No I decided not to use it. Even after cleaning it up I’m afraid of what might have been in it prior to my possession and I found a small fracture on the bottom. I fill it must have been some chemical in it besides beer. I still have it, I might make a grill or something with it.
 
Well I can’t leave this old thing alone so I decided to conduct an experiment with a stainless vessel to gain but nothing to lose.
 
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