Trade Secrets!

How to fix this guitar if my elbow's stuck in the soundhole?


Issue 142 June 23, 2011

Image: Curious Dan How can I fix this guitar
if my elbow’s stuck in the soundhole?!

Dan Erlewine, June 23, 2011
Photo: Dan Erlewine
Image: soap barHey, it actually happened to me! Years ago I got my elbow through a soundhole, then couldn’t get it back out. No kidding. I had to soap my arm to get it out of there.
Try doing that one-handed, while your other hand has somebody's guitar stuck on it! I felt pretty silly as you might imagine, and this isn't something I’ve talked about very often. ;-)
And it almost happened again last week.
This classical guitar came to the shop because its top was buzzing. Looking inside with a light and mirrors, I found the problem. At the tail of the guitar, there was a gap between the top and the tailblock.



Photo: gap at the tail block Pressing on the top outside, I could see a gap open and close inside. It’s almost too small to see in this photo, but it’s there: the lining between the top and the side had come unglued. Flexible Lighted Inspection Mirror
Photo: classical guitar troubles
This guitar must have suffered quite a blow. On the outside, there was a “crunch” fracture along the binding, and a long crack heading toward the bridge. A bit of staining showed where someone had tried to fix the crunch, and a light area along the crack was probably from their sanding.
Their glue at the binding held tight, but clearly the seam inside needed regluing. I couldn't get at it by wriggling my arm into this classical’s small soundhole. My arm was getting stuck, and no way was I going to go through that again!
Doing an inside job from the outside
Even with my fancy repair gizmos, I couldn’t maneuver well enough to get glue where it was needed, much less complete the work before the glue started to dry. Even if I could, my glue job would be sloppy as heck and hard to clean up. I decided to “think outside the box” by removing a section of binding to access the loose joint and get at the problem.
Photo: routing The wood binding had multiple layers divided by thin strips of maple. I used a ball-bearing binding router bit to remove the outermost layer of rosewood binding. I left the intricate inner laminations untouched. Removing the rosewood was enough to give me access to the joint.
Binding Router Bit Set
Photo: feeler gauges Now I could slide feeler gauges into the loose joint along its entire length.
I used the feeler gauges and an offset disassembly knife to apply Titebond glue to the joint. I drilled holes in the offset disassembly knife so it holds more glue. You might remember the small inset photo from Trade Secrets #104 which introduced this "swiss-cheesey knife" idea.
Offset Disassembly Knife
Photo: spool clamps With the glue in there, I clamped the joint shut with spool clamps: cork-padded dowels sliding on all-thread rods. The plastic straws protect the guitar's finish from the threads.
While this dried, I got ready to replace that section of rosewood binding I routed away.
Spool Clamps
Photo: bending iron I cut a strip of rosewood to size, soaked it in water for 30 minutes and bent it to shape on a bending iron.
Image: Dan goin' to bedAt this point, I left everything to dry overnight and went upstairs to bed.
Bending Iron
Photo: rosewood binding patch Day 2: covering my tracks
The next morning I shaped the ends of the rosewood strip to match the curves left by the router bit on each end of the routed ledge.
Now I've got a nice rosewood patch for concealing the site of my "surgery."
Franklin Titebond Glue
Photo: rubber binding bands I glued the strip in with hot hide glue, using rubber binding bands to clamp it in place.
Rubber Binding Bands
Photo: razor blade scraping When the binding was dry I filed, scraped and sanded the new wood flush with the back and sides.
Natural Wood Bindings
Photo: classical string tie Anxious to hear if the buzz was gone, I strung the guitar to pitch before touching up the finish.
Notice how the bridge tie-block has two holes for each string: the string goes though one hole, then back over the tie block and through a second hole before being tied-off. I’ve only seen this style of bridge on a couple guitars.
Classical Guitar Bridge
Photo: Curious Dan No buzz!
And I never even had to monkey around in the soundhole!
Later on, after letting the glue cure for several days, I would touch up the finish with a little French polish.

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