Sunday, May 13, 2012

Harmony H1203 Sovereign - Shine On You Crazy Diamond

Remember when you were young
You shone like the sun.

After a few evenings of trying to reset the neck, I mostly figured out what needed to be done.  A lot had changed with the angle of her neck joint since the last time I had the back glued on her, and it was clear it would take adding extra material to the neck part of the dovetail to get an angle that would bring her action down low enough.  I made some thin oak strips to add on to the pins of the dovetail, set her neck aside for the glue to dry, and moved on to preparing her body for some coats of clear lacquer.

I applied about a dozen coats of lacquer in the past week.  That brought back a lot of good memories of my experience with the classical guitar I built in the early 1980's.  Without the luxury of a proper dedicated workshop, I had to be much more resourceful this time.  A few old particle boards made for an impromptu spray booth, just enough to contain the overspray from getting all over the rest of my shed.

I prepared the back and sides of this old guitar by light hand sanding with some 150 grit, followed by a vigorous rubbing with some steel wool.  As a final step, I cleaned everything up with a paste of baking soda and water, applied with a toothbrush.  After allowing the paste to completely dry, I wiped off the residue with a clean, dry rag.

The first coat of lacquer appeared much darker where I had exposed raw wood on her back and sides.  Differences in texture and thickness between the areas of new and old lacquer were also noticeable.

After a few more coats, the color and texture variations became less and less noticeable on the sides, yet more noticeable in some areas on the back panel.

When I was pleased with how her sides had come out, I let them harden overnight.  Next, I taped up her sides, so I could avoid overspraying them while continuing to work on the back panel.

Although the old and new lacquer were not reacting, I sprayed on the new lacquer too thick in a few spots, too thick to properly cure in those areas.  I scratched the gunky mess away with a fingernail and some 150 grit sandpaper.  Frustrated, I ended up bringing those areas back down almost to the bare wood with sandpaper and steel wool, and built them back up with more coats of new lacquer.  Since I was spraying the entire back panel, the finish in these areas is noticeably thinner than at the rest of the panel.  To get any better results on the back panel now would involve sanding it all down level, almost to bare wood, and starting all over.  Although that's an option, I decided to stay with as much of the original finish as possible.  I can always come back and try fixing it with some brush-on lacquer, or completely refinish the back another time.

Her neck was in pretty good shape, so I tried to contain my work to where I had made repairs to the wood, at the back of her headstock and the joints between the neck and binding.

With successive coats of lacquer and sanding  in between coats with steel wool, the differences in color at the wood repairs got less noticeable.

But, my attempts to contain the finish repairs on the neck did not work well.  Some lacquer leaked beneath the tape and combined with the adhesive on the painted front of the headstock.  The resulting sludge ate away at the paint, removing some of the black as well as the first few letters in the word Harmony.  Disgusted, I pulled and rubbed away the sticky mess with a fingernail and some 150 grit sandpaper, and used some steel wool to even things out and give some bite to the old finish materials.

After a few coats of lacquer, some of the original colors in the decorative paint were showing nicely again.

When I had removed the tape from her neck, I could also feel some lines where the new lacquer met the tape. After smoothing out the bumps with steel wool, I put a few coats of lacquer on the back of the entire neck as well as at the edges and back of the headstock.  Except for a few deeper scratches in the back of the neck, the lacquer filled in the worn spots quite well, leaving a very smooth and hard surface.

I sprayed the final coat of lacquer on the neck and back, this time without any sanding to the previous coat.

I left the lacquer to cure for a full day before getting back to the neck reset.  When it's ready to be reassembled, I'll do some minor lacquer touchup to the front panel.

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