Step 4: Drill some holes and connect barrels
Position barrel halves with 9" overlap and tape using duct tape to hold.
Tape a flange spacer into place.
Drill at least four quarter inch holes through the barrels using the flange spacer as your guide.
Put in some 1/4" nuts and bolts to hold the barrels more firmly.
Drill large hole through barrels using the flange spacer as your guide (use a 4 1/2 " hole saw, coping saw, or rotozip).