my specialty........................... Here's how you do it. #1, if you now have 30 minutes, count the number of pins on the cam. Most timer clocks are either 60 or 180. (old ones I used to service went to 240 minutes). If you have 2 pegs on it, take the cam off and grind or chop off one of the pegs. This will give you 1 peg, = 60 minutes. If you have a 180 minute clock, then to get 30 minutes you would need a 6 peg wheel. If you want an hour, clip every other peg to get a 3 peg wheel. You get the drift. Most come from factory set for 45 minutes. They have a 4 peg wheel and a 180 minute clock on the whirlpools. 30 minutes is not a factory setting. If you are in doubt, look at the timer motor on the timer. It usually tells you the clock time. (180, 60, 30) etc. Good luck.