Oil canning comes from the metal being in an unnatural state,can be caused by shrunk or stretched metal.
In the cases of dents it caused by stretched metal unless any prior repairs were made then thats up in the air.
The dent is held in place because the that area is somewhat stretched and now tension exists on the metal holding the dent in place. Excessive amounts of hammer ON dolly will stretch the metal out leaving you hump of extra metal.
So you already have some amounts of stretched metal on your fender.
This is where heat comes into play, heat SHRINKS metal. Shrinking with a torch is hard to do and also shrinks metal that doesn't need to be shrunk. A shrinking disc generates heat through friction and ONLY shrinks the high spots or stretched metal.
The key is to use a combination of hammer and dolly techniques that will both raise the dented metal up and limit stretching.
you have two techniques and you use both of them but during different times, you must learn to read the dent and learn to use each method.
The other is Hammer ON dolly. the hammer and dolly hit in direct contact and thus stretch the metal out but because of this the metal expands and expands upward or raises up. This technique is used to pick up small areas of low spots, but use caution to avoid raising it too much. [IMG]http://inlinethumb33.webshots.com/41440/2800252890102553149S600x600Q85.jpg[/IMG]
A very good good dent repair video, he actually teaches you something and speaks!!
Last edited by sevt_chevelle; 03/03/20101:13 AM.
Currently working on custom metal and How to videos.
