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Old 08-27-2011, 08:31 AM   #1
Aug 2011
moline, Illinois
Posts: 4

My dad and I are getting all the stuff to start brewing and we're looking into storage vessels right now. Either we're going to have to bottle the beer, and that doesn't sound fun since we only have 1/2 as many bottles as needed for a 5 gallon batch and cleaning nearly 50-16oz bottles doesn't sound fun. Or, need at least one small keg and still bottle part of it.

I can get 5 gallon cornelius kegs for $30-35 shipped. The 2.5 and 3 gallon kegs are at least $100. My question is if it would work to cut the kegs, remove some amount of the metal and TIG weld the two halves back together? In theory, it should work, right? I may need another tank of gas to back purge the tank, or T off my regular tank.

Anyone know offhand what alloy the kegs are? Are they coated with anything, or just plain stainless steel?

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Old 08-27-2011, 10:56 AM   #2
Aug 2007
Southern Maine
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Don't bother cutting the keg, just put whatever volume what want in a 5 gallon keg and proceed as normal.

In theory it should work, but why bother? I don't know if your welds will hold pressure (i.e. if it is possible or if you are good enough of a welder to do it).

Kegs are stainless steel. Also, you will need nearly 50-12oz bottles for a 5 gallon batch, not 50-16oz bottles.

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Old 08-27-2011, 11:47 AM   #3
strat_thru_marshall's Avatar
Mar 2010
Oklahoma City
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your weld would have to be 100% sanitary and pressure tight.

Why not just brew a 5 gallon batch for your 5 gallon keg? Thats what most of us do.

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Old 08-27-2011, 11:51 AM   #4
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Apr 2011
Winston-Salem, NC
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The $30 keg is used and probably has not been refurbed. The $100 kegs should be brand new. A sanitary weld and one that looks good are two different animals. No offense, but if you are asking you probably don't have what it takes.
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Old 08-27-2011, 12:30 PM   #5
Beerrific's Avatar
Mar 2007
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It can be done. The problem though, unless you know someone that will do it for you for beer or free, it will likely cost you more to have it done than it would cost to buy a new 2.5-3 gallon corny.

Discussed here:

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Old 08-27-2011, 01:13 PM   #6
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Jun 2006
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I know Yuri_rage did one a few years back. I remember him saying it was not easy, as the stainless for the kegs is very very thin.
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Old 08-27-2011, 02:35 PM   #7
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Dec 2010
Acworth, Georgia
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Welding may not be the right mindset. Brazing with stainless steel silver phosphate rods would be my suggestion.
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Old 08-27-2011, 03:55 PM   #8
beaksnbeer's Avatar
May 2011
New Port Richey, Florida
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Years ago worked at a shop that made the Bunn ice tea tanks (make great fermenters) a tight weld that is sanitary it also has to be polished inside. I repaired several cornies some of my own. If you consider cost of gas 308L rods cleaning pads, a used 3gallon corny goes under 100 on

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Old 08-27-2011, 04:27 PM   #9
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Dec 2010
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Rebel Brewer has brand new 3 gallon kegs for just under $90 (plus shipping). Order two and the shipping per keg is really sweet (somes to about $13 to get two shiped to me). IMO you would be better off getting properly sized kegs than hacking up larger ones.

Also, it only takes about 36-40 pint bottles for a 5 gallon batch (assuming you're actually bottling a full 5 gallons. Most of the time I would get just under 5 gallons for bottles, so I dont think I ever used three cases of the swing top bottles.
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Old 08-28-2011, 08:11 AM   #10
Aug 2011
moline, Illinois
Posts: 4

My bad on the count, it'd take 40 bottles exactly if I got all 5 gallons, so more like 35-39 realistically.

I was unaware of how thin these kegs were. I was expecting a little thicker metal, like sheet metal on a car. 1/16" tungstens are small, but not small enough for that with limited means of sharpening them and polishing them fine enough.

PurpleJeepXJ, I'm looking for brazing rods but I'm seeing a lot of silver soldering stuff.

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