I received some suggestions on how I might go about pouring both the cement foundation and the cement sonotube piers at the same time. I am not sure the cement pouring company is going to go for that approach so it looks like I will need to pour the piers first and then call them back again to do a second pouring of the observatory foundation.
I am running out of time as the observatory construction team will arrive soon. I would appreciate some advice as I am clearly not very experienced or knowledgeable about the procedure for pouring the observatory's cement foundation in conjunction with a cement pier. My previous observatory's foundation was wooden decking so I just had to pour the cement pier base and sonotube but did not need to keep it from mingling with a cement foundation.
If I pour the pier base first, what kind of material might I be able to wrap around the protruding part of the cement base before having the cement foundation poured all around it? I imagine that just using some plywood to separate them while doing the foundation pour would not be sufficient as it would probably be really difficult to pull the plywood up out of the floor once the cement had dried. Is there another material that you could suggest? Ideally, it would be stout enough so that it would not be crushed between the pier foundation and pier base when the foundation was being poured, yet easily removable after it dried. Is there a certain kind of foam that might do the trick? I thought of using bubble wrap but knowing my luck the bubble wrap would all burst when pouring the foundation.
Would appreciate any ideas from those of you who have more experience than myself.