I use a squirt bottle with a touch of liquid soap added. The soap allows you feel the metal better.
When you torch shrink you will see the metal start to raise, making a "bubble" in the metal.
Once this bubble starts put down the torch and grab a hammer and dolly. If you are not seeing some type of metal raising up then get the metal hotter.
You will want to use the hammer OFF dolly method, otherwise you will stretch the area you are trying to shrink.
http://www.imagestation.com/picture/sraid225/pc358365c47a5b1e8d9ce6a72452beb94/ea387981.jpg Place the dolly on the backside of the bubble on the pretimeter(sp?) then hammer the down the bubble.
Work from the outside inward in a spiril motion, this will trap the bubble from escaping and shrink the metal. Once you have hammered down the "bubble" cool it with water...Eric
P.S just remember the ONLY spot that needs to be shrunk is the high spot. Do not shrink anything but the high spot.
