Monday, February 11, 2013

Jay Turser JTA-Flag300 - These Days

These days I sit on corner stones
And count the time in quarter tones to ten, my friend
Don't confront me with my failures
I had not forgotten them

At the time of my last entry in July on this project, I had this guitar making music again.  Here you can see my son diggin' on her before even I her new preamp arrived and before I had a chance to put on the truss rod cover and some other finishing touches.

During a few relatively cool evenings, I made some cosmetic repairs to the bass side of the neck.  After spraying and feathering in a few coats of clear lacquer, I reinstalled the neck for what I had hoped would be the last time.

A few days after taking these pictures of this cosmetic neck repairs, the strap and preamp I ordered from an eBay vendor in China finally arrived.  That turned out to be a combination of pleasant surprises and downright disappointment.  The pleasant surprises were how well the strap goes with the colors of this guitar, and that the output module has both high and low impedance outputs.

The disappointment was in the size of the preamp.  In converting centimeters to inches, or between Chinese and English, I ended up with a preamp that was about 1/2 inch too small in length for the existing opening.  Maybe the Chinese words for "overall" and "cutout" are similar, but on this part of the project, the difference is like night and day, or success and failure.

I could either try making a plate to cover up the gap, or just cut my losses and find a right-sized preamp.  Knowing it would be awhile until I got back to working on a solution, I put her in a case and let her sit for awhile.  After a few weeks, I took her out to play and found she was terribly out of tune.  It was then that I realized the neck joint repair was not holding up.

The only thing holding the neck in place was a reworked dovetail joint and a single bolt into the heel.  I took out the retaining bolt to have a better look.  Although the metal insert I had put into the heel was holding up well, the force of the strings in tension proved to be just enough to work her neck loose and start riding out of the heel block.  With her thin body, there's very little depth in the heel and neck joint.  In an attempt to solve this, I routed out a the end block and attached a thin oak plate.  My hope was that closing the groove with wood around the retaining bolt would provide enough stabiltiy.  Although the plate held up under tightening, it was not strong enough to hold the neck from twisting out of the block under string tension.

An attempt to put a metal insert in the block also resulted in failure.  I refilled and redrilled the hole in the block.  As I installed the insert, the force was enough to split the re-filled and re-drilled hole.  As I tightened up the retaining bolt, the compression force began pushing the neck out of the block, indicating the inserts were out of alignment.

There just isn't enough room for stacking a pair of metal inserts and bolts through the heel and into the block, and that doesn't leave many choices for making a strong joint and setting the neck angle.  A very tight-fitting dovetail joint with some hide glue might be all she needs, but I'm still not convinced there is enough depth for the joint and glue without resorting to an epoxy, a la Jay Turser and Ovation.  Besides, I only have one of these guitars, so some trial and error to develop an accurate bench-tested jig for getting the right neck set angle is not an option.  Some additional bolts beneath the fingerboard in the direction perpendicular to the strings and through the neck into the heel block, with some shims in between to allow for seting the angle, might be just what she needs.  It would be a cross between a set neck and a bolt-on neck  All of this calls for removal of the fingerboard to work on the dovetail joint and neck angle.  So, time to remove the nut, measure the fingerboard location on the neck and fire up the Black and Decker iron...

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