Huey, Dewey and Louie,
See here some of my barrels.
The smallest is useless for us I gues 2.5 liters
the middel one is the first refurbished one 12 liters and recharred,problem was it was leaking and leaking I had to renew the sedge gras between the hatch and the barrel wall,and added a very small amount of flour egg white water filling ,result barrel ok,to reduce the angles share I waxed the outside exluding the hatches with bee wax.
This one is topped up with wine and grape extract distilate.
The largest one 22 liters I took it appart and found out very minimal burn spots so this one needed realy charring,this morning i did the job and took some photo's ,right now the barrel is closed again and slowly filled with water.
If you ever take a barrel appart add duck tape to one end in that way an accident falling the barrel appart when the rings fall of is avoided.
Further if you charr the barrel , protect de end part where the hatch should fit in,I used alu foil.