Part 1…. Martin HD-28 Neck Reset
Due to a high string action and very little saddle left this 1980s Martin was in need of a neck reset. After taking the appropriate measurements with the guitar tuned to pitch (neck relief, top rise, and angle) it’s time to start the plan of action. First the tongue (the section of the fingerboard that is over the body) needs to be loosened from the top. To do this, I like to use a heat blanket to warm the tongue and soften the glue joint. Using a thin spatula to separate the joint. Making sure to use the right amount of heat and working slowly to eliminate prying spruce from the top.
Once the tongue has been separated, it’s time to steam the neck joint itself. This model was constructed using a dovetail joint. This is the traditional way of installing the neck to the body of an acoustic guitar. To do this, the fret above the end of the dovetail needs to be removed, and a small hole drilled into the fret slot that will access the dovetail cavity. In this case it is the 15th fret and needs to be drilled on either side of the truss rod. This hole will be plugged later once the neck has been removed.
I use a jig that helps me remove the neck by adding a small amount of pressure to the bottom of the heal. This jig pushes upwards on the heel to aid in the removal of the dovetail from the neck block. Next, it’s time to apply steam into the hole with the use of a small hose and a hollow needle. Using the correct amount of steam and pressure from the jig will soften the glue, and the neck can be successfully removed from the joint.
After the neck has been removed, it will be time to remove the old glue from all surfaces. Next, the heel will be recarved to restore the neck angle, and the correct mahogany shims will be made to tighten up the dovetail joint before glueing the neck back on. On this guitar I will use hide glue to glue all the joints back together.