8/13/2015

Workshop: Another Way to Skin a Cat


So -- this is a gorgeous Martin "Wurlitzer" koa uke. Its main problem is that the action is too high at the top of the saddle by about 1/32" -- so it'd play with 3/32" action rather than 1/16" action at the 12th fret. Most old ukes were setup that way from the factory from what I've gleaned... but we can do better, these days!



So... I measured that virtual action height and, like I said, it was 3/32" at the 12th fret. What to do? One could slot-down the saddle but then the string would be riding on the "meat" of the bridge. One could shave the bridge and put a new saddle in, but that destroys the vintage glossy look of the original finish on the bridge.


I decide to remove the bridge. A couple knocks with a dead-blow hammer and my "paint scraper seam separator" (I've sharpened it a lot) and the bridge pops off...



Now that it's off I'll measure the "virtual height" of the ideal saddle/bridge height by making a "virtual" action of 1/16" at the 12th fret...


...and then measuring what the height at the saddle area should be. In this case, it's 1/4" tall.


Here I've marked the front edge of the bridge with how much material I want to remove from the front of my bridge. I then sand the foot of the bridge down with a slight slope that builds to the rear to preserve as much stability in the bridge as possible.

After that I clean up the string ramps and mounting-holes for the strings and reglue it...


After I dab a bit of clearcoat around the freshly-glued edges of the bridge, I doubt anyone would expect the bridge had been modified at all... and as a bonus I get to keep that interesting original maple saddle!

I use violin "f-hole" clamps to reglue all uke bridges except for the nastiest of randomly-warped tops which require more pressure to seat them properly for a glue job. This Martin's top is dead flat and in good order so this is an easy reglue.

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