Our spankings don't last too long. My wife is a very rapid spanker. Depending of why the child is getting spanked we will set the kitchen timer, Recently our 9 year old son got the hairbrush from his mom for 45 seconds. It doesn't sound like a long time but she can dish our about 3 spanks per second so his little hiney was a deep red when the timer went off.

I always follow up my wife with the strap. So after the hairbrush I had him standing up and gave him 10 good licks with the strap. That lasted about half a minute.

On our younger kids my wife uses a thin ruler - again very rapidly paddling his or her little hiney and thighs. We set the kitchen timer to between 15-30 seconds with no breaks in the spanking rhythm.