With the top to its final graduation, it's time to fit the bass bar. To keep the top from flexing, I clamp it onto a simple frame made of plywood.
Prior to clamping it on the frame, I laid out the position of the bass bar, and glued temporary studs to help me put the bar down in the same place each time. It needs to be fit to the curvature of the top.
After planing the bass-bar blank to its final thickness, I start out fitting by eye, then use carbon paper (ink-side up), then go to chalk for the final fit. Once it is fit, I glue it into place with hide glue. I'd like to have a few more clamps, and will have to get serious about making some -- more of them, and smaller. But for now, this works.
After letting the glue dry overnight, I take the clamps off, trim off the temporary studs, and layout the profile.
Using a large flat gouge to clear off most of the overhead -- needed with the clamps and frame I use, I then go to fingerplanes and finally scrapers to shape the bass bar.