Here is a quick drawing for a water bottle buffer. Step 1: Insert the defective bottle in the hopper and close the lid.

The cleaning and buffering solution is applied to the workpiece and it engages a rotating buffing wheel. This removes all imperfections and takes only half a minute.
Hand restoration of these bottles takes almost a half hour.
Step 2: Once the bottle is rinsed and air dried open the cover and remove the now ready to fill water bottle.
An automated version that detects imperfections in the line and diverts them to a automatic buffer, and then returns them to the filling line.