Kay K6150 Acoustic Guitar

The bridge had already been detached by this point and
was just set back onto the guitar for the photo

I've have the honor of working on a very clean late 60's Kay K6150 flat top "super auditorium" acoustic guitar in a "golden cherry" finish. This model was made from 1966 till 1968.

This guitar was a product of a struggling Kay Musical Instruments and the market flood of cheap Japanese built guitars, these were some of the last models built in the US before Kay was bought out. The instrument has some glaring design flaws that I've not seen in earlier Kay models which leads me to believe that quality control was on a downward slope

Previous Repairs

The guitar has had a bolt attached through the heel of the neck and bolted to the neck block from inside the body in an attempt to keep the heel from lifting; it didn't work. Luckily the drilling was done well and neither the dove tail nor the heel block were cracked from the bolt

The bridge was shaved flat in an effort to bring the strings down to a playable level. The saddle slot was cut deeper too and the bridge modification seems fairly professionally done.

Mystery species of Rosewood bridge (7"x1.25")
with stock decorative brass bolts

Issues 

The bridge has been bolted down to the body with 3 bolts, two decorative ones that I know are stock and then a third solid brass flat-head bolt that I cannot determine its originality. The bridge was lifting from the back and cracked between the pin holes which I determined to be caused by the chewed up bridge plate. The bridge was about ready to pop off and I only needed a little heat to encourage some stubborn spots which, as it turns out, the bridge was glued directly onto the lacquer finish. There was no attempt made to scrape the lacquer back or even to score or rough it up; the bridge was glued right onto the finish and bolted down which is why it failed to stay put.

The neck joint's glue failed years ago and after removing the aforementioned bolt I discovered that the neck had an impressive amount of wiggle room. The hole for the bolt made for an easy entry to the dovetail for my steamer and I removed the neck fairly quickly since it was already so loose. I was shocked at how loose the dovetail joint was after I removed the glue. Most guitars I can put the neck on dry and it'll fit pretty snug but this guitar's block barely makes any contact with the dovetail; no amount of glue will help hold that joint together.

I've been asked to fill the neck bolt hole with a strap button which I believe is totally feasible and the strap button is an easier approach to hiding the hole.

Solid spruce top bound with checkerboard binding

Repairs

I am going to carve a new bridge for the guitar out of a block of Indian Rosewood which will match the color and grain of the fretboard a little closer. I'll scrape the lacquer down to the wood underneath the bridge footprint in order to get a very solid wood-to-wood bond which will improve the sound and strength. The bridge plate will get a maple cap that will support the ends of the strings and keep them from putting excessive pressure on the top and bridge that leads to cracking and lifting bridges

The neck joint will be shimmed with maple until the guitar can be strung up without any glue and then I'll check the angle and glue the neck onto the guitar. That will improve the tone and the stability of the neck joint for years to come

The strap button hole will be filled with a dowel and a button will be attached