Part seven picks up with the frets having been installed and the excess clipped off.
The next step in the fretting is to use a file to file the ends of the frets flush to the edge of the fingerboard. I use fret clippers to get it as close as possible when cutting off the excess, and cut with the “blades” parallel to the fret tang so it doesn’t get bend when the excess is clipped off. Then with a file I file in the direction of the tang until the fret ends are flush. The fret ends then need to be beveled so that they are smooth as the hand is moving up and down the neck. There are fret beveling files for this job, but I’ve always found that sanding with an random-orbit sander with 200-grit just a great job, and makes quick work of the beveling. After the fret ends are beveled, I take 400-grit sandpaper and gently roll the fingerboard edge to create a smooth, slightly rounded surface. Here is a shot of the fret ends at this stage.
There is one more treatment for the fret ends, but this will wait until after the final sanding has been done.
The last step before final sanding is to cut the nut slot. The fretting template leaves me with two “slots” that mark the edges of the nut slot. To finish the slot, I cut these slots to depth, then I take a .020 hand saw and cut a third slot between them. Then with a little pressure I can pop the wood out due to the wood grain. As you can see in the shot below, it is important to drill the truss rod anchor hole deep enough that the brass anchor will be to the fret side of the nut. The brown line in the middle of the nut slot is the walnut plug. This is preferable to having to file the anchor if it is not drilled and set deep enough.
Once the slot has been rough cut, I clean it up with the edge of a file.
I use a bone nut blank and cut it to size, leaving about 1/32″ proud on each side of the fingerboard. I glue the nut in before I shape it, clamping both sides. It can take a few tries to get the nut slot perfectly flat, so I just test and file.
The pencil rides on the first and second frets, and gives me a marker for shaping the nut.
Of course, I won’t shape the nut right up to this mark, but it gives me a good guide. I then carefully shape the nut on the drum sander. An important note is that bone dust is a huge concern. I use a mask whenever I sand bone. The bone dust with calcify in your lungs if inhaled. Bad news later in life. Here is the nut shaped and flushed on the edges. In this shot, you can also see a little filler drying on the side of the nut, there isn’t really a gap, but I fill it just to be safe. When the finish goes on, I want the neck to be perfectly smooth.
Now it is time for final sanding of the neck. I start with a random orbit sander using 200-grit paper. This takes off wood really fast, even on maple, and even with 200-grit paper. Once I get the neck cleaned up with the power sander, I take the sheet of, and roll it by hand.
The sanding pad for the orbital is rigid enough the do a good job. I hold it on the ends and sand in an up and down motion. I do this again with a sheet of 300-grit, then 400. I repeatedly check the sanding with a bright light. The biggest lesson that I have learned about finishing is that it will never make work better, only worse. If there is a flaw, dent, or scratch in the wood, it will be twice as bad once the lacquer goes on. Lacquer is much thinner than it actually looks, and will not hide bad sanding, it will make it worse.
The last step before finishing is to fill the fret ends where the slot may be a little deeper than the fret (this is inevitable, and it is always better to cut a hair deep than too shallow), and the skunk stripe. Maple is not a porous wood, so it does not need to be filled. Walnut, however, like mahogany, has very open pores which need to be filled so that the finish doesn’t show lots of little holes. Usually I fill porous woods with oil-based grain filler. For a neck like this, since it entails such a small area, I just use Elmer’s wood filler. This stuff is available at Home Depot or Lowes, works great, dries rock hard, and takes shaded finish well. I use oak for the fret ends, and walnut colored filler for the skunk stripe on the back of the neck.
Here is a shot of the filled fret ends. The oak color is slightly darker and yellower than the maple. This is actually perfect. Although the filler advertises itself as being “stainable,” when the amber lacquer hits it, it doesn’t color the filler as much as the maple, which absorbs more. In my experience, if I use a filler the same color as the raw maple, it shows up as too light once the ambered lacquer goes on. This shot is before the filler has dried and been sanded.
After sanding with 400 grit, it is nearly invisible:
Before the skunk stripe is filled, I mask off the maple. It would sand out if it got on the maple, but I don’t want to mess with that.
The stripe is then filled.
And then sanded with 400-grit paper. This filler is hard, but sands easily.
The next chapter will begin the finishing stage.