Fine tune RMH by amount of cob covering barrel ?

First let me say hello to everyone ! I appreciate this site and all who contribute to educate and empower us with the knowledge found here. Thank you to all, I have been lurking for quite awhile learning as much as I can before starting my own project. On to my question ;

I was reading about using a RMH with the barrel combined with a bell. I know running the system out of energy by using too much of a battery, (heat sink) so that we get moisture and a stall is a concern regardless of the battery type. Can I use the amount of cob covering the barrel to fine tune or direct more heat into the battery, in the case of too long of runs or too much bell mass ?

That would likely work, provided you have enough draft from other elements in the system so that you aren't depending too much on the downward pump from barrel radiation.

If you are concerned about your build absorbing too much heat, you may also have sluggish draft especially at startup, and would probably benefit from a bypass to quickly warm the chimney before diverting flow through the mass.

In that kind of design, I would also strongly consider making the top of the barrel removable (Ernie and Erica Wisner have at least one design that shows this option) so that if needed you can just pop the top open for inspection, and cleaning.

Yes, making the barrel top removable would be essential if the sides are partly cobbed over.

I can definitely see the need for a removable top in that situation, I may pass on that idea just because I want it simple. I'm glad you guys are on the ball, lol.