Base stays on to keep coffee hot, post brewing.
Upper globe can bubble out from under lid if dwell time is not adjusted right.
Detailed Commentary
I&lsquove had this machine for 4 months, I purchased it becaus I like vac pot coffee better than other brew methods and I needed a way to make coffee in my office.
The machine is a start and forget brewer, however I have added a thermos so that I don&lsquot have the coffee under constant heat post brewing. The dwell time is adjustable by prying a small metal plug off of the bottom of the base. Clockwise increases, counter clockwise decreases.
This is a good vac brewer, and is ideal for someone who doesn&lsquot care for all the extra care needed to make vacpot coffee (I mean the whole watching thing while it&lsquos under heat :)