1966 Gibson Trini Lopez with Separating Fingerboard

[Robbie Collins]

I did a setup on an old cherry red Trini Lopez today and, as I held it in my lap to set the intonation, I noticed a crack along the bottom of the binding near the neck joint. I was able to shove in a pick, so I stuck in a metal trowel thinned and shaped for fretboard removal and found that the fingerboard had separated from the 12th fret to the end of the fretboard.

My first thought was "O my God, what did I do?" before realizing that restringing to pitch isn't abusive ;-)

My second thought was to just reglue the loose section. Then I considered

1) I might get glue into the truss rod slot;

2) it would be difficult to clear out the old glue;

3) that section of the fingerboard would probably be higher due to the additional glue; and

4) the guitar would need a fret leveling if not a fingerboard leveling & refret.

Before noticing this, I checked the relative height of the frets using a Fret Rocker and it seemed every other fret was high. Also,the truss rod was cranked hard when I received it but the neck had about .10 relief. I unstrung it, loosened the truss rod and using a board, two blocks, and a clamp tried to straighten it but the neck retained some forward bow after restringing.

I try to consider each repair approach in terms of the probability of solving the problem. Since so much of the fingerboard is loose, the fingerboard might need slipping, and it needs at least a fret leveling, I'm wondering... Would it be best to remove the entire fingerboard, reglue it so that its flat with minimal tension on the truss rod, level and refret?  I obviously don't want to oversell my customer, but I also don't want to return a guitar not properly repaired and/or with a chance of coming unglued again. This approach seems to me to have a very high probability of success.

However, there's an old saying about engineers...anyone can design something. The trick is building it with the least materials and labor. I tend to over-engineer for safety's sake so I'm looking for help on determining the best method that minimizes cost to my customer but doesn't unacceptably lower the probability of making a long-lasting effective repair.

Here's a photo of the guitar and trowel. The crack goes higher...I'm trying to avoid cracking the fingerboard along the runout if the top section is still adhering.

Now, please check my as method. If regluing only the lower part of the fretboard I'd

1) remove the neck pickup, put in a small bubble wrap bag and tape out of the way,

2) Tape up the upper bout, use 320 grit sandpaper and pull it between the neck and fingerboard,

3) Blow out crevice and tape up the neck close to the crack to protect from hot glue,

4) Heat fingerboard to 150F using heat lamp and surface thermometer, and

5) Using an 8" maple caul with a 10" radius slotted for the frets,

6) Reglue with hot hide glue using wax paper between caul and fingerboard using a palette knife to spread glue. I'd mark the palette knife so that I don't get near the truss rod.

7) Re-evaluate frets.

If regluing the whole board I'd get an LMII adjustable fingerboard clamp, locating pins, etc.

Any and all help appreciated!

[Eric Steven Johansen]

Robbie, Remove and reinstall the entire board. Something ain't right with that glue joint, that it let loose in that way, so I'd be questioning the whole joint. You may get really lucky and find the frets just need a dress after you reinstall the board. You're methodology for the process' are sound. Cool guitar. 

[Robbie Collins]

After a few detours with other guitars, I'm back on this guitar. The fingerboard is off. I had to remove all the inlays and reinstall them as they loosened from the heating blanket.

Here's a shot of the fingerboard extension:Question: Am I correct in thinking this guitar has been repaired before as evidenced by the blocks on each side or was this just part of the manufacturing method?

Notice the divots on the left side which I'm now filling. The sides and rear of the neck show no damage so this is probably not part of a broken neck repair.  Could there have been some sort of rot, perhaps dry rot?  The fingerboard is very soft and light sanding produces a lot of dust. Should I use wood stabilizer on it?

[Paul Verticchio]

Hi Robbie.

OK, here's my guess....

I view the added spacer blocks as factory work. I base my call only upon the condition of the area around the neck joint. It shows no evidence of repair, only normal stress.

My vote goes to Gibson using existing non-reverse Firebird necks on these. The blocks were used to adapt a neck tenon designed for narrow morticed solid body to a wider mortised ES body.

I've, personally, never seen this type of construction. Anybody else see this before?

This is definitely the "surprise photo of the month." This model Trini is the poor man's 335.  Great guitar!!!!

Best of luck :)

[Robbie Collins]

Paul - thanks for your comment ... it makes a lot of sense - adapting existing Firebird necks. Seems rather rather more like carpentry than woodworking though. I mean, why two blocks instead of one and why are the gaps so large?

Both the left blocks and the fingerboard are soft. Would you happen to know why? Is is caused by dryness, fungal rot, or something else?

[Paul Verticchio]

"Is is caused by dryness, fungal rot, or something else?"

Those would be my first assumptions. Perhaps tighter tolerances in the joinery would have prevented this (and it's probably the impetus for the FB separation).

I hope someone with more/better info chimes in. Like I said, these are only my uneducated guesses :)

On one hand, my mind wants to yell "What in the world????" but at the same time, there's a part of me that's saying "good save". It, otherwise, doesn't seem to be causing any other issues.

As I said, a VERY intriguing situation. :)

BTW: that guitar would look and sound stunning with an ebony FB. I think your concern about the softness of the original FB is well founded. If replacing it is a possibility, might as well upgrade :) Again, these are my personal observations :)

[Mark Griffiths]

Hi. I’m very interested in seeing the update to this. Hope it’s going well. I have a neck build which i will be putting up on here when I’ve finished. Cheers Mark.

[Robbie Collins]

Mark...here' a photo of the completed guitar:

Here's a blog of the process:

http://macon.craigslist.org/msg/4164670716.html

It turned out nicely. The owner didn't want to pay to repair per-existing finish chips along the fretboard seam, but it looks and plays fine.

[Mark Griffiths]

Thanks for the post. Looks great :D

Do you have any more pictures? 

[Robbie Collins]

Anything in particular?

[Mark Griffiths]

Removal of the fingerboard and the full neck without the board? I need to figure out a way of removing whats left of my neck without causing unnecessary damage to the body. 

I will be using a hollow needle steaming the neck joint. I’ll need to know which frets to remove for the job.

Cheers Mark.

[Robbie Collins]

Check photos 2 and 5 in the blog link I posted above. 

I used an LMI fingerboard heating blanket and my homemade controller set to 250 degrees. To separate the fingerboard from the neck I used a thin masonry trowel (Home Depot, corners reshaped on the grinder) as well as StewMac's Seam Separation Knife.

My fingerboard was already separated at the end but I'd probably tap a single-edged razor blade into the very end of the fingerboard seam to get things started. I was able to move the blade about 2-3 inches at a time, reheating the board in between. 

I basically followed the procedure Dan Erlewine used on one of his Fretting DVDs to slip the fingerboard/neck joint and correct excessive bow including making cardboard/aluminum foil strips to protect the binding. I used a Harbor Freight infrared thermometer to check the temp of the wood after pulling off the blanket.

You mentioned steam - to remove the neck or fingerboard? If the fingerboard, I'd give it a fairly low probability of sucess.

To keep the blanket snug against the neck I made this caul from 3/8" plywood and a 3/16" dowel: