This article describes the steps on making a chased wedge T-fold as described by Charles Lewton-Brain.

To begin with a loop is made from a rectangular piece of sheet metal.
The loop is placed into the vise and the jaws clinched tight onto the loop. You can see the angle the loop is tilted to in the vise. Vary the angle to alter the results. Note this is also a very quick way of making a conical form in metal.
The end of the loop is now malleted down, ‘confirming’ the position of the table relative to the legs. Clinching the end first leaves a hollow shape to the rest of the loop. This is called a pillow, and is used to chase into.
Begin the procedure by creating several sideways dents in the pillow. These sideways indentations prevent the loop collapsing as the chasing work proceeds.
Use hanmers as much as possible to shape with as it is more efficient. As well large broad movements are done earlier in the process, and this is faster than using chasing tools or dapping tools at this point.
Chasing begins. It is important to slide the tool across the metal to keep the marks smooth.
Many of the indentations are worked sideways rather than just pushing down. Stop and look at what is going on now and then.
You program curvature during unfolding by thinning the places you want to curve more. The thinner (weaker) a particular place is the more easily it bends upon unfolding.
The most interesting lines and areas are produced by varying the thicknesses of the raised areas. Do not be shy about really working it. The harder you work it the more the metal expresses itself, and the more lovely the results.
Whenever possible use the hammer instead of a punch as it delivers more force, thins better and is faster.
Here you can see how a hammer is used very accurately. Always hit a steel hammer with a softer one, leather, wood or weighted plastic. Hitting steel on steel can shatter a hammer and blind or injure you. Using a hammer as a punch like this is a great way of working the metal and efficiently shaping it.
Again, you program curvature by thinning and the hammer used this way does a good job of thinning, and in this case, forging the fold out. The lessons learned in making simpler T-Folds all apply here.
Here is the chased T-Fold lifted out of the vise. Feel free to work it further, and even to anneal it, puff it back out again with soft hammers, replace it in the vise and continue chasing. Usually though this is not necessary.
Here the chased T-fold is annealed. Make sure and turn it over repeatedly, washing it with flame until you see that all areas are annealed. (Watch for an orange flame leaving the metal to tell this)
The fold is opened with the fingers, levering it back and forth as necessary.
Here it is unfolded.
This is a back view of the fold.
A picture of a different chased T-Fold.
Here are two regular T-folds that have been chased into. The one on the right has been flattened somewhat. Thinner raised areas become line folds, and these line folds can vary in width as well as curve, unlike standard line folds.