A wood hammer is a good way to go but sometimes you need a wood dolly or buck.
How to use dollys to straighten out sheet metal.
Fabricators heat metal so it does not have as much tension when the fabricator uses force to straighten out the metal.
They place the metal on either an anvil or a straightening plate.
You also have to grasp the fact that you can reduce the area of sheet metal by thickening it.
First use your shrinking hammer and see what you can do to tighten up the metal with that.
Body files are usually used after another age old process has been used to straighten or shrink sheetmetal.
Working on the dolly is the use of a back up block directly behind the point you are hammering on.
Plus tips and tricks for using them.
George just barely touched on a key concept.
This will tighten up that specific spot.
This technique stretches the metal.
Put your dolly behind the metal use your shrinking hammer and smack the metal using the dolly to absorb the impact and accept the rebound.
You have to adjust your mind to the concept that when you hammer on sheet metal with a steel hammer onto a steel dolly or anvil that you will expand or increase the surface area by thinning the metal.
Any time you hit sheet metal with steel hammer against a steel dolly it stretches.
Very important do not let the dolly rebound onto the metal.
Understanding how metal deforms is the first step toward straightening it.
Work it on dolly until it is straight.
It may result in too much shrinkage but we know how to deal with that.
Working quickly bump the high area down with the hammer while supporting the neighboring low area with the dolly fig.
The best is to use heat a wood hammer and a dolly.
Fabricators generally use locksmith hammers light metal hammers mallets streaming hammers and rubber hammers to straighten the metal.
Using wood you eliminate one of those hard points so the metal can move without stretching.
Work the metal until the area temperature falls to normal because the metal continues to shrink until it is cool to the touch.