Size of the opening of a RoCC kiln

Reinould,     (also sending to others who can  appreciate this clear statement about the size of the opening of the RoCC kilns regardless to diameter or length.)

You asked about the size of the opening: 

On the curvature of  the cylinder:    Consider the face of a clock.   The  opening is from 1:00 to 3:00.   That would be 60 degrees of arc.   Could be 75 degrees.  But never from 12:00 to 3:00 (90 deg).   And  from 2:00 to 3:00 is rather
small.

The length is ALMOST the length of the Cylinder.   At each end of the opening there should be an appropriate strip of metal all the way around the cylinder so that there is strength for the end pieces and in case there is to be a “path”
for a roller that helps hold up the cylinder (in addition to the  support by the axle stubs at each end).

Note:  There is NO pipe or axle in the  center of the cylinder body.   Axle STUBS are attached to the two end-plates.

Note:  Large cylinders can bow out their ends when hot, even a few inches at each end.   

Paul