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Acoustic Guitar Neck Reset – Part B

August 23rd, 2010

Acoustic Guitar Neck Removal Part B
Source: Guitar Neck

Acoustic Guitar Neck Reset – Part B:

Since resetting an acoustic guitar neck is a rather involved process, we will split this process into several different articles.

In the last article, we left off at the point of removal of the fretboard from the 12 or 14th fret to the sound hole.

In this article we will discuss removal of the neck, by means of releasing the glue at the dovetail joint.

Since the fretboard removal gives us easy access to the dovetail (or mortise and tenon joint), we can now proceed with removal of the guitar neck from the guitar head block.

Occasionally this process is quite easy, as the glue joint is old and possibly even has failed completely.

You can check it out by grasping the neck with one hand and the trying to work the neck joint back and forth. If you can, then this will be a very easy process for you – check out the Ultimate Guitar Repair Tip below for information on this.

Tools and Materials:

20 gage Hypodermic Needle:
Hand Scrapers:
Wood Clamping Cauls:
Double-Stick Tape:
4″ x 8″ Bessey Regular Duty Tradesman
Wood Chisel Set

Ultimate Guitar Repair Tip: If you find the guitar neck is already loosened, you may not need to separate the fretboard separately from the guitar neck. You can simply work a sharpened spatula beneath the fretboard to separate the fretboard from the guitar top and you can separate the neck from the guitar very easily. If it does not dislodge, follow the clamping procedure outline below.

Glue Softening Recipe:

This is an old trick my father used to use to get old wooden furniture joints apart.

Mix up a solution of 1 part rubbing alcohol, 4 parts water and a few drop of dishwashing liquid. Mix it thoroughly and fill an long-needle hypodermic needle full of the solution. Carefully squeeze the solution into the dovetail joint as deeply as you can insert the needle and let it stand for a while.

You will find that most of the time there is a gap between the back of the dovetail joint and the front of the head block, which will allow the insertion of the needle very easily.

Work The Joint Loose:

Next slip a long sharp blade, like a sharpened sawzall blade into the joint as far as you can. If you leave the teeth in tact, you will be able to work out old softened glue while you are at it. Work the blade back and forth and continue to go deeper. If you can’t complete the dis-assembly, squeeze more solution into the joint with the needle and try again.

Clamping The Neck Off:

Now we need to force the joint apart with a Bessey Bar Clamp.

Lets start by fashioning three 3/4″ plywood blocks. The first one is designed to fit around the dovetail joint while supporting the top (see diagram at the top of this article). The next one will be a long block to support the body of the guitar just behind the bridge and the third one supports the neck at the nut.

Note that the block at the nut needs to be trimmed down in thickness, to compensate for the fretboard thickness.

Attach the two blocks on the body of the guitar with double stick tape. Now place the guitar face down on the workbench.

Make sure your Bessey Clamp has a padded jaw, otherwise use a small piece of wood to protect the heel block. Apply the clamp over the heel and apply pressure on the dovetail joint with the clamp, by twisting in some pressure.

If you did your glue softening trick adequately, as outlined above, you should be able to ‘pop’ the neck right out. If it is stubborn, inject some more glue softening mixture into the dovetail joint and let stand for about an hour. Try to clamp the neck out once again.

Clean The Joint Thoroughly:

Once you have the joint separated, carefully clean all of the glue off the joints of all surfaces. On the neck, this is easiest done with a metal hand scraper or a very sharp chisel. As for the head block, use a sharpened chisel. Check your work and do not let any old glue remain as this will compromise the joint.