1940s Kay Jumbo Guitar (X-Braced Conversion)




This guitar has led an interesting life. Before it even got here, the fretboard had been replaced (and refretted, of course), an adjustable truss rod had been installed, the bridge was replaced, the neck was reset in the past, and it'd received a maple bridge plate cap. It actually played pretty well right out of the shipping box and whoever did the fretwork on it was quite accurate.

However, the owner wanted me to rebrace this to get some more mwah out of it and that was my primary work. I think it came out the other side of brace conversion a killer box. It still has some of that Kay "sizzle and snap" to its sound (it is a Kay with ply back and sides -- let's be fair), but the overall voice is close to something like a D-18 crossed with a '50s Gibson J-50. It doesn't have the "scooped" Martin sound -- it has much more of that balanced, mids-front Gibson voice -- but the slight velvet on the highs and lows reminds me more of a D-18.

Anyhow, it has an absurd amount of punch and volume and kicks it out very easily. There's a lot of reserve power in this guy -- in the clip I'm trying not to hit the mic with too much of it.

This type of Kay jumbo was built through the '40s but it changed to a less-classy-looking variant of the same general idea by the '50s. In that decade it lost its cool-as-heck tortoise binding, veneered headstock, and mahogany neck in favor of a poplar neck and painted headstock with white or cream binding and darker-colored back and sides. I think this earlier version is cooler but it's also more like a "0000" in the way it handles as the back is shallower than most jumbos at only 4" at its deepest.

Repairs included: previous neck reset, truss rod install, replacement fretboard, and replacement bridge. My work included rebracing the top to a "Bohmann-style" double-x-braced pattern (click here to see that evolution), a new bone saddle, mod to the replacement bone nut, general mild cleaning, replacement '50s-era Kluson tuners (the original '40s Klusons were really loose and skipping turns on a couple posts), and setup.

Setup notes: it plays perfectly with 3/32" EA and 1/16" DGBE action at the 12th fret, strung with 54w-12 gauges. The neck is straight and the truss rod works as it should. The frets are nearly new and in good order.

Scale length: 25 5/16"
Nut width: 1 5/8"
String spacing at nut: 1 1/2"
String spacing at bridge: 2 1/8"
Body length: 21"
Lower bout width: 17 1/8"
Waist width: 10"
Upper bout width: 12 1/4"
Side depth at endpin: 4"
Top wood: solid spruce
Back/sides wood: ply mahogany
Bracing type: double-x-braced
Fretboard: rosewood replacement (Martin-style scale length vs longer original)
Bridge: rosewood replacement
Neck feel: slim C-shape, ~12" board radius?

Condition notes: aside from all of the modifications listed above, the finish has also received an overspray job on all edges save the fretboard. It's over the original finish, however, so it still looks good.



Here's a quick shot of the bracing pattern while I was working on it.














Comments

Hey Jake!
Really ENJOYED your little article and great photos of the old Kay..
Nice Job Lad!
Greetings from San Diego!
Harry