Neck fitting

I ordered some trapezoid inlays which were delivered, but I forgot and left them at work over the weekend. Instead of working on the fretboard, I turned my attention towards the neck joint, which needed a little fettling to get the small gaps tightened up.

Here's the joint before starting:

It's not bad, there's a little gap on the bass side. To remove this, you need to sand down the shoulder of the neck on that side. However, once one of the shoulders is changed, you also have to start adjusting all the others (on the heel, and then the other side of the neck).

First, I attached the Fricken Laser Bean to the body, so that I'd easily be able to check that the neck was straight as the joint was adjusted:

The beam runs along the centre of the body, like so:

... And should hit the nut, right in the centre of the neck. In this case, it was (annoyingly) a couple of mm off - which gives another reason to adjust the neck joint:

This isn't really a big deal - it's a tiny amount which can be compensated by pulling the neck slightly to one side as it's glued, or by mounting the bridge *slightly* (a mm or so) off centre of the body. However, since we're adjusting the neck joint, we should be able to correct this properly.

To adjust the neck joint, you basically need to remove very small amounts of material from the neck tenon. As you do so, the angle it fits into the mortice changes slightly. You need to be careful to remove tiny of material, as each removal makes the tenon smaller, so the joint less tight. I did this in conjunction with getting the neck's "shoulders" tight against the body.

One way of getting the neck and body joint tight is to put strips of sandpaper between them, and pull the sandpaper from side to side. This way is very slow:

But eventually starts to yield results by tightening up the gap:

Another way to check which bits of the joint need adjusting is to heavily coat the end of the body in chalk:

Once the neck is then offered up to this, the bits that are touching will be white, and should be removed (by sanding or gently chiseling):

After an hour or so, I ended up with a neck that was totally flat across the top of the body:

With no gap on any side of the neck joint. Bass side:

Treble side:

 And underneath the heel:

You can see in this photo on the left that the body needs a little material removed to meet the neck properly. Not sure how that happened, likely a combination of template misalignment and the robosander bearing not quite matching the size of the sanding drum, but I'll address that shortly!

I forgot to take a picture, but the tweaking of the joint also straightened up the neck, so the Frickin Laser Beam now strikes the centre of the nut.