I mostly do the backsides of my necks in one operation…..because I have no neck/body angle although I’ve done it both ways.
I use a roughing operation from a crude, squared blank. With a little tweaking, the speed of removal on a roughing operation ought to remove any thoughts of taking risks with band saws and such. I leave .1” on all surfaces for roughing operations. This is usually done with a ¾” ball nosed endmill. When roughing, I always cut the outside contour line first and then work in….which eliminates edge tear out.
For the finishing op on the main length on the neck a 1/2" bull nose endmill is used with a corner .03" radius and a surface operation with a step of about .1". Using a bull nose cutter cuts back on the sanding as compared to using a ball nosed cutter. The cut is oriented 90 degree to the neck. I’ve seen some factories going 0-180 for these cuts but I seem to get better, more predictable results going 90 degrees across the neck.
For the volute the same cutter is used with a finer surfacing step over of .025". This cut is broken down into two operations, one for each side, cutting on a 45 and a 135 degree angle respectively.
For the tenon I use matched, left and right rotating end mills and attack the wood from each direction such that the cut cannot pull out on the surface edges on cross grain cuts. On my main design, the neck is not angled to the body. On a Les Paul there is a 6 degree angle to the body so this operation must be done with a second operation. I can't describe the fixture except to say that I ALWAYS use an aluminum tooling fixture to be able to locate precise origins on my tooling.
The back of the headstock is cut with a surfacing operation using a ½” ball nose cutter. This time the orientation is 0 - 180 up and down the headstock using a .05" stepover. Before that, however, a 3D contour path is run right down the middle of the outside contour line of the headstock using a ½ ball nosed cutter. This removes material that could potentially rip out during this surfacing operation.
There is, perhaps, an interesting trick I use to establish tuning peg hole position. When cutting the back surface of the headstock, the surface is 15 degrees relative to the cnc table. (D)imples are programmed into the model on back of the headstock in the proper position for the tuning pegs and then are cut with a 3D contour operation. This allows registration of the headstock into a fixture with corresponding (p)imples so that cuts can be made on the face of the headstock that register perfectly to the rest of the neck.
Lastly, on the backside set of operations, the rough outside edge of the headstock is cut using a flowline operation, leaving .1" on the edge. This extra material is removed later in a final operation that occurs after the headstock facing is glued into place. The dimple/pimple part and holding fixture relationship facilitates that final cut and maintains the relationship of the headstock profile to the tuning pegs and the inlays.
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That little light spot on the heel is from not leaving enough waste when bandsawing out the rough shape before milling.