Concept for a fermenter

[Griffsta]

I need to make a fermentor large enough to ferment a 10 gallon batch. Here is what I was thinking.

Cut the bottom off of a small pressure cooker, and TIG weld the top of the pressure cooker pot to the top of a keg (with an approximate 6" diameter hole cut). Saw off the handle and drill a hole into the top of the lid for my air lock.

Does anyone see any problem with this?

Does anyone have any better suggestions?

 

[Seabee John]

There are a multitude of threads on this site dealing with the conversion of kegs for fermenting. I think retrofitting for the use of the seal-able lid of a pressure cooker is a unique idea (I have not seen here before). Just make sure the person doing the tig welding know's what they are doing and can perform a sanitary weld from the inside. Are you planning on a dump valve for the bottom of the keg?

 

[Griffsta]

I was planning on putting in a 1/2" ID ball valve. That way, I could simply boil a little water in the fermenter prior to putting the wort in there, to be sure it is nice and sanitized, and be able to pour everything out easily. Is that what you mean by "dump valve?"

What do you mean by a "sanitary weld?" I dont know that you would be able to weld that from the inside, unless the modified pressure cooker pot was sitting on top of the keg top, rather than inserted slighty into the keg, which would make sense to do it that way.

 

[Dwain]

I would talk with my Welder. You will probably want to cut the hole ~1/16" - 1/8" smaller than the pressure cooker. That way, s/he can reach inside the pressure cooker and T.I.G. it so that the weld is accessible/cleanable (sp?x2). So yes, set the cooker completely on top of the keg. As far as a dump valve, it sounds like you're just putting a valve to drain the wort from the fermenter for bottling/2nd staging. If that's the case, make sure the 1/2" ball valve is not tubed right to the bottom or it will plug all the time. Have it take-off from a little way up the side. There are some pretty good dimensions in these threads. If you're talking about a dump valve to dump the trub kind of like a conicle fermenter, then you will need a bigger valve. Also, I've read some discussions that say the bottom of the keg is not angled enough to use for a conicle. I have no experience with the keg as a conicle but I don't think it will work well with the bottom angle. But, one winter in '63 I was almost wrong about something. Luck - Dwain

 

[Bobby_M]

What kind of keg are you think of using? What's the point of putting a pressure cooker lid on? If it's to do pressurized ferments, drilling a hole for an airlock defeats the purpose.

If you're just trying to use a 1/2bbl keg and have a large cleaning hole, just put a piece of 3/8" acrylic on top with a rubber gasket and hold it down with some square tubing run under both keg handle holes.

 

[Griffsta]

The purpose of using the pressure cooker is simply because it is stainless steel, and I can weld it to the top of the keg, and it allows me to have a sealable lid to put on/off of the keg. The intent is not to build pressure, as I would install a hole for an airlock. Essentially, I just want to use a keg as a fermenter, and have a top that I can screw on and off easily.

I have seen the flat piece of acrylic (or whatever material) on the keg held down using the keg handles, but it seems to me that it would be likely to develop leaks, or not have a sealed surface, allowing the slight possiblity of contamination. I probably just worry too much...

 

[FSR402]

The purpose of using the pressure cooker is simply because it is stainless steel, and I can weld it to the top of the keg, and it allows me to have a sealable lid to put on/off of the keg. The intent is not to build pressure, as I would install a hole for an airlock. Essentially, I just want to use a keg as a fermenter, and have a top that I can screw on and off easily.

I have seen the flat piece of acrylic (or whatever material) on the keg held down using the keg handles, but it seems to me that it would be likely to develop leaks, or not have a sealed surface, allowing the slight possiblity of contamination. I probably just worry too much...

Repeat after me... "the primary fermenter does not have to seal, it just has to keep things from falling into it"... Now keep repeating that until it sinks in.

 

[Bobby_M]

I'd rather have a simple one piece lid that *might* leak a little instead of a potentially unsanitary weld.

 

[IwanaBrich]

Seems like a lot of work, what about using one of these 15 gallon water tanks, Cone Bottom Inductor Tanks ??

See this threat for more info. https://www.homebrewtalk.com/f11/15-gal-conical-i-put-together-77550/

Sell the presure cooker on ebay and use the proceeds to buy the 15 gallon :rockin: