The first step in shaping the underbevels on the top is working the top to it's finished dimensions and fairing the curves on the front edge.

Before any shaping can begin, layout lines are drawn to define the finished geometry.

How did I shape the underbevels on this top? Hand planes. I take pretty aggressive cuts at this point, but will begin to work more precisely as I get closer to the layout lines

That's me, in the orange shirt, planing away.

Working it closer to that layout line...

...and we're there.

The finished bevel.

Shaping like this creates lots of hand plane shavings. But I'd much prefer these wispy shavings to the dust and noise of trying to do this with machines. Plus this is a whole lot safer.

Shaping the underbevel on the front edge - the edge with 2 curves - is done in much the same way except I start by hand sawing down to the layout lines. I'll then remove the material in between kerfs, starting with a chisel and mallet, then switching to a drawknife, spokeshaves and files.

Close-up of the saw-kerfed edge. Notice the layout lines - they are so important in achieving the final shape.

All of the edges on the top of the chest of drawers are shaped with an underbevel. I love this edge detail and have used it on quite a few pieces in the past. Besides the aesthetics of this detail, I love it because the shaping is done completely with hand tools. A tedious process, but definitely worth the work.

The top of this chest of drawers is a bit different in that the front edge has two curves which reflect the two curves in the drawer fronts and base. The first two images below illustrate these curves. Shaping the underbevels on the ends and back edge (the back edge is straight, no curves) is straightforward. But shaping the under bevels on the two front curves required a slightly different approach. If you skip ahead to the last 2 pictures (the first 8 show how I work a more typical bevel) I started by hand sawing down to my layout lines. These angled saw kerfs define the material to be removed, and they act as a kind of "safety" as I use a chisel and mallet to remove the chunks in between the kerfs. Without the kerfs, it would be fairly easy to remove too much material whether through an errant swing of the mallet or uncooperative grain. Once the bulk of the material is removed with chisel and mallet, I switch to a drawknife, then to spokeshaves and files, continually refining the shape until I hit those layout lines. Notice the progression of the tools used - roughing material away is done with tools suited for that task - a drawknife and mallet-propelled chisels (yes, chisels can do really fine work, but in this instance it was their brawn that I needed). Then the switch to spokeshaves and files reflected the need for more precise final shaping.