Paul Chenoweth asked me to come onto the post to help answer some questions and after reading some of the posts regarding growlers I would be happy to answer questions.
To introduce myself, I have been making primarily nothing but growlers for over 6 years - both turned and cast. One offs and mass production. I have worked with huge breweries around the country (Widmer, Kona, etc) and have sent my growlers all over the world. You can see some of my stuff at
When I first began making growlers there was A HUGE learning curve to get the shrinkage, top fitment and function just right.
As I read through the previous posts, a couple of things that jumped out at me are the following:
1. Growlers are not meant for bottle conditioning home-brews. Don't even attempt it as you cannot control the living portion of the process (sugars and yeast) you will end up with a huge mess!
2. Flip Tops DO NOT RELEASE CARBONATION, they are made in such a way as not to budge - unlike the screw on tops for the glass growlers. Those are actually made to release pressure and give much like when you pop open a jelly jar for the first time.
3. Carbonation-CO2 is not your friend. As CO2 comes out of solution (as beer warms) carbonation will build up inside your vessel. If you do not have a strong enough clay body, or the type of top that releases pressure, something has to give. I spent a lot of time with my local head brewer going over their carbonation/ temp charts, and did a lot of pressure testing on my growlers. I built a pressure tester and have blown up more growlers than you would ever imagine - recording the PSI, body wall thickness, temps, etc etc.. I would recommend doing the same type of testing before offering them for sale. I learned the hard way that people hate it when beer explodes all over the inside of their car!
4. Flip tops. The small Grolsch style tops are too small for growlers and most filling stations or brewery hoses won't fit. The 34 mm size is the style I prefer. The wide mouth ones work really great too. Both styles are hard to source but if you are looking for them in bulk, I would try Saxco Pacific. If you want just a handful, call the guys Sound Homebrew (or go to them online) - i get orders from them within 3 days usually.
5. The flip top bales I use can be slightly "adjusted". pull the two pieces apart and the bracket that holds the topper, those arms can be straightened and re -bent higher or lower depending on if you need a little more room or a little less to make it a tight seal. If you can close the bail and still rock the stopper back and forth, it is too loose - tighten it up a bit.
6. Growlers are a temporary storage device, meant to get beer home, or to a party and then used. I have however kept beer good, in my growlers for almost two weeks - IN the refrigerator - keeping that beer nice and cold and the carbonation down. I have at times popped the top to releases a little of the pressure just to be sure.
7. Growlers are a blast to make and more fun to take to the local brewery - learn your states regulations (and those of any states where you might have customers) some places require by law the legalese Gov Warning label. Some states have totally crazy laws -others are way more lax. It sucks bringing one and finding out you can't fill it.
8. Brewers make money by the ounce. You gotta have your shrinkage rate dialed in and the sizing just so.
Hope that helps. If anyone has specific questions, please feel free to email me at email@example.com
Best of luck and happy turning!