Harmony Neck Reset

This Harmony H162 guitar is at least 40 years old.  Harmony made these here in Chicago, they made them with solid spruce or cedar tops, and they can be pretty good guitars.  This one, although it shows a lot of evidence of use and wear, is in excellent structural shape.  All it needs in order to be a good “player’s guitar” again is a neck reset to correct the neck angle and restore the action to an acceptable height.

Harmony_Before

Harmony_Before

Harmony_BeforeHead

Harmony_BeforeHead

This is a cut-through bridge saddle.  Vintage!  Even with the saddle height as low as it is here, the action is painfully high.  The neck reset will correct that problem.

Harmony_BeforeSaddle

Harmony_BeforeSaddle

The owner of this guitar also asked me to install an endpin jack in it for his soundhole pickup.  The tail block in this guitar is so thick that a standard endpin jack is too short to work.  But someone’s had one of those screw-in-from-the-outside kind of jacks in here before, as evidenced by the threads cut into the hole in the block.  Suits me fine, I’m going to get another jack like that and wire it up to the pickup, rather than fighting with the thick tailblock dilemma.

Harmony_BeforeTail

Harmony_BeforeTail

The first thing that has to come apart for the neck reset is to free the fretboard extension from the top.  Heat and a palette knife soften the glue and open up this joint.  Of course there are more specialized heating units for this task than the one you see here.  But this works well with care and patience.

Harmony_DuringFB

Harmony_DuringFB

The thin palette knife gradually gets insinuated in there and separates the fretboard from the top.  You can also see here that I’ve pulled the 15th fret in preparation for the next step.

Harmony_DuringFB2

Harmony_DuringFB2

Now a small hole is drilled through the 15th fret slot, into the gap between the neck block and the neck dovetail.

Harmony_DuringFretHole

Harmony_DuringFretHole

With an espresso machine, some fuel line, and a piece of 1/16″ stainless tubing for a steam needle, I’ll put steam into the neck joint through the hole in the fret slot.  Here you can see the steam hose and needle, and the jig and clamps used to put pressure on the joint to slide it apart.

Harmony_DuringNeckSteam

Harmony_DuringNeckSteam

“Slide it apart,” eh?  By alternating between steaming the joint, wiggling the joint, & applying clamp pressure to the joint, it should release right at the glue lines and literally slide apart.  This time, however, a piece of one side of the dovetail stayed put in the neck block when the other side released.  Not a show-stopper, but now I have to rebuild the dovetail.

So I cut away the damaged part of the dovetail, revealing a good gluing surface.

Harmony_DuringDovetailCut

Harmony_DuringDovetailCut

. . . .and make a repair graft out of mahogany, and a matching angled clamping caul with some sandpaper on it to keep it from sliding around.

Harmony_DuringDovetailCaul

Harmony_DuringDovetailCaul

Here’s the graft clamped up, with some wax paper behind the caul so I don’t glue the caul to the cheeks of the neck tenon.

Harmony_DuringDovetailClamped

Harmony_DuringDovetailClamped

And here’s the graft glued on and marked where I’m going to carve it into a dovetail again.

Harmony_DuringDovetailGraft

Harmony_DuringDovetailGraft

After cutting this back into a tapered dovetail tenon with a chisel, I can move on to fitting the neck joint.

Harmony_DuringDovetailDone

Harmony_DuringDovetailDone

First I mark a line around the neck heel, where I’m going to remove a tapered slice from the cheeks of the tenon in order to alter the angle where the neck joins the body.

Harmony_DuringHeelScribed

Harmony_DuringHeelScribed

After cutting that slice out with a chisel, I adjust the final fit between the neck and body by pulling sandpaper through the joint.

Harmony_DuringHeelFitting

Harmony_DuringHeelFitting

After the heel is fitted to the body, I shim the neck block and fit the shims to the dovetail until it fits tightly, pulling the neck heel to the body.  Then it gets glued with hide glue in the joint only, no glue between the heel and the sides.  Here you see it glued and clamped and fitting nicely.  Hide glue is used in this joint and also to glue the fretboard back down to the top for a couple of reasons – first because it doesn’t creep under pressure, and second because that’s the kind of glue a future repairman would expect to encounter here.

Harmony_DuringNeckGlued

Harmony_DuringNeckGlued

Now it’s time to replace the 15th fret &  make a new bone bridge saddle. . ..

Harmony_DuringSaddle

Harmony_DuringSaddle

. . . .and install that new endpin jack. . . .

Harmony_DuringEndpinJack

Harmony_DuringEndpinJack

. . . .and after installing the soundhole pickup, this guitar is ready to go home.  With a fresh set of strings and a setup, this guitar plays and sounds great – it’s ready for another 40+ years of music-making!

Harmony_DuringPickup

Harmony_DuringPickup

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2 Responses to Harmony Neck Reset

  1. Dave Gilson says:

    Andy, I just love these. I find them really interesting, and I am blown away by your skill and craftsmanship. I can’t wait to see more.

  2. I came to your site through a Google search for information on repairing a guitar male dovetail. I’m currently working on a 1915 Lyon and Healy Jupiter and am in the process of making sure I get a good well-aligned, tight fit for the dovetail joint. Your descriptions are helping me. I appreciate your documenting your work and making that information available for the benefit of others like me who need models for sound practices in lutherie.

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