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2 1/2 gallon Montana Jar Fermentor

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Reviving an old thread here, but just wanted to chime in by saying that these 2.5 gallon Montana Jars are my FAVORITE fermentors for brewing beer. I always brew small batches between 1-2 gallons (usually stovetop BIAB), and almost always use these. Online merchants like Northern Brewer have made a big deal of their "Big Mouth Bubbler" fermentors of late (basically driving Better Bottle out of the market, from the looks of it), but they don't sell a small size version. That's basically what these Montana Jars are!

Originally, I attempted to use an airlock with them by unscrewing the brushed metal lid from it's white, plastic underside (where the silicone gasket is actually attached), and then widening the hole in the middle of the plastic part of the lid slightly to fit a rubber grommet and then the airlock. I then attached stuff to the lid with Command Strips (unused picture hanging hooks in this case) to make sure the lid didn't fall into the fermentor when you put it on!

This way, by using the hole in the center of the plastic for the airlock, I could
use an airlock with the jar, but not destroy the metal part of the lid.

BUT...I ended up having problems with the lid not holding pressure enough to make the airlock do anything. If you look close, you'll see two holes in the silicone gasket (all of these jars come with these holes), which I tried to fill up with hot glue, and ultimately failed. Also, over time, if you use a fridge to control fermentation temps (especially lagers), the plastic will eventually crack.

LONG STORY SHORT...I eventually gave up on the airlock altogether and went much lower tech. Now, I don't use the lid at all, and just stretch plastic wrap over the top of the jar, use a large rubber band to secure the plastic wrap around the jar lip (which flanges out, by the way, conveniently making sure the rubber band doesn't accidentally ride up and come off), and make one very tiny pin prick in the center of the plastic wrap, to relieve fermentation gas pressure build-up.

That's it. Works like a charm, and I've never (in the 4+ years I've been doing it) had an infected batch. I'm pretty confident in the CO2 blanket produced by the fermentation (provided you don't get in there and mess with it a million times) and its ability to keep bad stuff out. Anyone who practices open fermentation obviously does too, and this plastic wrap method is much lower-risk than that.

If you want to measure internal temps with a thermowell and probe, take a sacrificial plastic lid to something (Oxy Clean works pretty well, but it just needs to be wider than the jar opening), drill a small hole in the middle for the thermowell, put the lid over the jar, cover with plastic wrap as usual, and then just poke the thermowell through the plastic wrap and hole (no need for an additional pressure relief hole). The rubber band will keep the plastic lid centered, and the plastic lid will keep the thermowell centered. I use this method if I'm using my heating pad/mini fridge to control temps.

They're sold at a lot of places, like Target, Bed Bath & Beyond (20% off coupons!), even Amazon (Prime shipping!) for around $20.
 
hmmm. this does look like a great idea. my tiny ass mash tun cooler is actually big enough to handle a 2.5 gallon batch. come to think of it my kambucha Walmart cookie jar is about that size and isn't really being used..... I like where this is going.
 
Cool idea for a small fermentor, and yes I know this is an old thread, but I just bought one of these thinking I had a good idea, just to find there really is nothing new under the sun...
Would probably also be good as primary for small batches of country wine...
 
FYI, anybody building this should know there's a little hole molded into that silicone gasket. I think it's there as an intentional feature to allow you to remove the lid (the silicone forms a pretty tight seal). So, if you add an airlock, plug the hole with silicone caulk or a glue gun. Alternatively, if you aren't worried about a fruit fly following the scent into that hole (my worry), just use it as-is, without an airlock.

montana.jpg
 
Looks like the handle is attached to the lid via a nut. Anyone try removing this handle and putting an airlock in the resulting hole? Might not work because the lid looks like it's a friction fit, not threaded. I'm guessing the lid be almost impossible to remove if you did that.
 
Looks like the handle is attached to the lid via a nut. Anyone try removing this handle and putting an airlock in the resulting hole? Might not work because the lid looks like it's a friction fit, not threaded. I'm guessing the lid be almost impossible to remove if you did that.

The lid's silicone insert is held by the nut. I think the nut has to stay. Though, I'd recommend replacing the nut with a stainless one - mine rusted.
 
Here's a couple other options...

Walmart, $15, and you can jam silicone tubing over the spigot. I'm aging a port wine in one of these right now.
https://www.walmart.com/ip/Circleware-Yorkshire-Mason-Jar-Beverage-Dispenser/35588833
42839fbc-8e03-4027-8631-705d52f552ec_1.e127a41f6b1d804dfd2e113297aaa746.jpeg


I have two of these 2.5g Uline.com carboys that I use for sours. Spigot is shaped for attaching tubing and it has a bigger hole on to for additions and a large (#10 iirc?) Stopper will fit in that hole for a an air lock.
https://www.google.com/search?q=Uli...&ved=0ahUKEwiblOuprPHQAhVY42MKHdddD9YQgTYIvQE
shopping
 
The lid's silicone insert is held by the nut. I think the nut has to stay. Though, I'd recommend replacing the nut with a stainless one - mine rusted.
I first tried removing the nut in the center (along with the brushed metal cover of the lid), and enlarging the hole slightly with a drill so that I could use an airlock with a rubber grommet. I attached three 3M Command strips and some extra wire picture hangers I had on hand like a tripod to serve both as handles you could use to pull off the plastic lid, and to make sure the lid didn't fall into the fermenter.

That plastic inner lid will eventually crack, especially if it's exposed to inclement temperatures for long periods of time (like if you keep it in your garage).

I tried plugging up the holes in the silicone gasket with hot glue, which worked for a little while but eventually lost its ability to hold pressure. This is why I eventually just ditched the whole thing and now use plastic wrap and rubber bands to cover the top without any sort of airlock. You COULD just use the whole stock lid by itself (I've never actually tried that), and it should provide an adequate (though not airtight) seal. I wanted to use a thermowell and temp probe, which is why I went with my Oxyclean lid/plastic wrap combo.

I have access to a 3D printer at work, so if ever I get around to it, I may try to design some sort of custom lid for these Montana jars that would work something like a "Snapware" lid, with a groove for an o-ring of some size, as well as holes for an airlock and a thermowell.
 
Another option out there is the Brew Demon 3 gallon plastic "conical" fermentor. It's only $40, but I wish it had a valve on the bottom instead for trub/yeast removal instead of the somewhat arbitrarily placed "sampling" valve on the side. In the end I didn't think it provided any real benefits over the Montana jars at twice the price.

What MIGHT be worth it, if it existed, would be a mini version of the "Catalyst" fermenter made by Craft-a-brew (resold also by Northern Brewer), which is a clear plastic conical fermenter with a huge butterfly valve on the bottom onto which you can screw mason jars or a bottling attachment. The current version is 6.5 gal (and also wildly overpriced at $199).
 
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