Its a great idea.
Ok you take a 42 gallon Blichmann (we have 6) and make them ?% bigger. lets say 50%
now you are brewing a 62 gallon batch. mmmm.... I like it
Whats the down fall.
1 Its much taller. These things are about 6 feet tall now
2 Heavier to role around A fixed unit might be ok
3 Double gasket and clamp to hassle with
4 Heat generation from fermentation. Its hard to control a 42 gallon unit you might loose it without adding a cooling system if you go much larger ie more money
5 Whats the cost for the additional section? a 42 gallon unit is about $1,200
6 Now i have to up grade my brew kettle (its 55 gallons)
Ok the other way to think about this is to buy a 27 gallon unit for $800 and add on your own 15 gallon extension to make a 42 gallon unit. Or in this discussion adding on something more.
still its a stretch
I am interested to see other comments