I was an early adopter of the CBS BIAB system and figured that I should share my experiences. We put together my rig before Tim was selling BIAB systems and my whole system is pretty much custom. My system is similar to what he is now selling as the nano bewer dual system in that I have 2 20G Kettles that can run simultaneously. I am extremely happy with the system and Tim has been a pleasure to work with. I highly recommend CBS anyone who is looking for an electric system and you really cannot beat the price for what you get. While the kettles and welding are not as pretty as some of the expensive stuff, they work well, are sanitary, and having the triclamps exactly where I want them is totally awesome at a fraction of the price.
I use brewsmith and am happy to share my 5.5 and 11G profiles. At 70% output, I get ~ 1.25G/hr evap. I get > 85% mash efficiency. My overall brewhouse efficiency works out to around 67-70% with 5.5G and 72-3% with 11G. This is due to the fixed kettle / chiller losses which are ~1.5G. I can eek a little more out if I tilt the kettle, but I only do this for light beers with minimal hop debris. I use a CFC chiller and whirlpool full throttle until the output is at the desired temp (the cooling liquid is ~ 35 deg so this works really well). When doing hop stands, I turn off the cooling liquid and let it whirlpool, then resume cooling when ready. I get a decent pile of trub/hop debris in the center, however it is not nearly as tight as what I used to get before switching over to electric. Thus, the wort in going to my fermenters has a lot of trub, but I am not sure that that really matters much to me except when trying to collect yeast. I think some sort of a trub damn would be a nice addition if it did not hinder flow, but based on the trub xbmts from brulosophy I dont really sweat it.
I had my mash basket fabricated from arbor fab (this was before Tim started making them). My basket is entirely mesh, not the new ones with solid sides. Reading though these posts, I think a lot of the problems that people are having is due to not whirlpooling the mash strong enough coupled with the solid sides. I believe Tim came up with the solid sides to ensure that the whirlpool is really strong when used with the arm that he is selling. I imagine that it will work much better when doing full sized batches as the mash will be thinner. Perhaps slowing the pump flow is actually making the slow drainage from the basket worse as it may drain faster if the mash is not settling on the bottom. I have a port though the lid that I attach a long piece of silicone tube to. I wrap it around the basket a few times so that it stays in place. I found this to be key to making the entire mash swirl in the basket. Once I got this worked out my efficiency improved and became much more consistent. I never had problems with slow drainage as my whole basket is mesh
As far as calibrating the sight glass, mine increases 0.89 inch (22.66mm) per gallon. Unless Tim changed 20G kettles, this should work for you.
Here are the profiles and a pic of the system before I got the second kettle set up.
Cheers!
:rockin:
