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I might be buying one of these. It needs a neck reset, and the truss rod wrench is missing so I don't know if that works.

Questions:

1. Is the wrench 5/16 like modern Gibsons?

2. If the nut is seized, penetrating oil, gentle wiggling and patience? Any other tips?

3. Does anyone know if the neck joint is glued with HHG? I believe I've read so for 6 string Gibsons of that period.

4. Any special tips on Gibson resets?

Thanks in advance.

These can be a nightmare and there is no telling until you're far into it....

1). I don't remember but I also don't remember any issues with these.

2). Sure.

3). Yep HHG dovetail joint.

4). Gibson on some of these tenors and many of the L-OOs of this period set the dovetail BEFORE gluing on the top... So the top gets glued on over the dovetail making the reset much more difficult in that you have to cut part of the top away to remove the dovetail. Here's the rub. There is no telling which ones are like this and which ones are not until you release the fret board extension from the top and have the neck steamed loose. Now remember too in removing a neck it's a huge help to have wiggle room as the glue softens. With the dovetail covered and effectively pushed back down in the joint we lose wiggle room and the neck is trapped in the pocket.

So working on one of these is not for the faint of heart or someone who has zero experience with neck resets AND vintage instrument finish repair because you will need to touch up around the joint to do justice to the instrument.

Expect more issues as well especially if it needs a neck reset. Other common issues are the bridge is either lifting or it has already lifted and has a sub standard repair. The bridge plate should be checked for pin hole damage and the pins migrating upward pulling the string balls up into the top. This is very common on these. If looking at the bridge when tuned to pitch the pins look too proud it's a tell tale oaf bridge plate damage.

The last one we did required a neck reset, loose back brace reglue, the bridge plate capped and repaired, new bridge, new saddle, new nut, fret dress, tuners removed and reconditioned and the tuner buttons may need replacement as well. Yep it can be a big job.

Thanks Hesh for such a detailed reply.

I did more research after posting and found all these things mentioned except the bridge plate. I'll check that out, but I can see from the pictures I have that the bridge is original and undisturbed and the pins are seated properly.

My plan of action is as follows:

1. Free up and adjust the truss rod so I can get the relief right and then recheck the action at the 12th. Currently relief is around 20 thousandth, so reducing it to something near normal will change that. However, current action at the 12th is around 9 or 10 64ths, so a reset is probably needed unless I stick to the lower frets when playing.

2. If the truss rod nut is seized, remove the fretboard and fix. At that point I'd remove the neck, unless that's a bad idea.

3. If relief can be adjusted, reset the neck. I'm not very experienced, but this is mine, not for someone else, and I can go slow. I'm wondering if it's sensible for me to use the old method, removing the fretboard extension. That will mean I can see if the dovetail is exposed, and also be certain I'm getting heat into the neck pocket. I know it's not ideal, but might help me do a better job. Any thoughts?

4. Finish touch up. The finish has lots of play wear, through the finish in places. Except the neck/body joint, of course! Would touch up with blonde shellac be sensible, to seal bare wood without causing irreparable changes?

You're very welcome Chris. What are you a professor of, I'm just curious. My third Dad was a professor of public health with the U of Michigan so we have academics or had academics in my family. My second Dad was a Professor or Psychology at Wayne State.

I like that you make plans too, I do that as well.

1). Sounds like a good plan. Some kind of break free anti corrosive dripped into the nut and using positioning and gravity to your advantage with some time and maybe if the nut is seized it will loosen up. Give it at least a couple days to soak. We've never had one completely seized before but it happens. If it needs a neck reset will be a function of how it looks after the truss rod is functional, the nut slots have been cut, the neck relief adjusted and then take measurements at the 12th. If there is saddle left it can come down too.

2). Fret board removal is a huge deal and although it gets mentioned on here on this forum it's not a practice that successful commercial shops do unless an instrument is in for thousands of dollars of restoration and major refinishing too. It should be avoided it's not a normal or usual repair remedy. This is a historic and cool old guitars minimalism and excellent work are really warranted for these in my opinion. Let's see if the nut can be freed with lubricants.

3). Don't remove the fret board extension that's considered hack work these days and no one but the people who do not know what they are doing will do this to a cool old guitar. As for getting heat in the joint you will know you are successful simply by observing where the steam probe is inserted, how deep it goes and if there is any wiggle to it once inserted. So because of my warning that the tops often cover the dovetail on these once you see that it needs a neck reset you are committed if you proceed to reset whatever you encounter in the process. That's the rub. Now it can still be reset with the top over the joint but you will have to cut an access opening and do so without damaging anything else. You will also see that you have steam in the pocket at the joint softens and steam starts migrating out the heel, body joint.

4). Shellac is fine it's benign and reversible so you still have all your options at a later date to use nitro if you wish.

Good luck to you and good on you for wanting to fix her up. This is a big project and all the operations that I detailed above would take a skilled repair person a week of their life maybe and we would charge $1,200 or more to do all of this if we took it on. We don't accept shipped in work and we have WAY more work than we can do so this was just an example of what a quality brick and mortar shop with professional luthiers who guarantee their work, are insured, pay taxes in the states might charge for your reference.

Professor of Electronic Commerce law, amateur builder and occasionally gigging musician, that's me. The day job is too fascinating to abandon for the penury of performing, plus I'm not top flight as a musician.

One more query if you have patience. If I find that this is built with a covered dovetail, are you saying that I remove a piece from the middle of the fretboard (14th-16th frets) leaving the edges intact? Or at that point, do I just cut through the 14th?

There's really no need to cut out any portion of wood on a covered dovetail. Here's a method for getting them off.

The first thing is to determine where the opening is. You simply drill into the fretboard like normal.

Once you find the opening in the fret slots take a fresh razor blade and score the fret slot repeatedly but *only in the middle* and not to the edges of the board. I leave maybe 3/16 to 1/8 of space at the edges of the Once you've scored it 10-12 times without cutting the edges at all. Take another fresh razor blade and cut it in half. Take the one half and tap it through the scored portion to sever the wood fibers there. Do it for the full width of the dovetail that you can find with your drill. Once you've cut the spruce there you can remove it like normal. This method will let you completely hide what you did and you won't have to blend in a new piece of wood. And you preserve the overall integrity of the fingerboard.

Gibson typically used very narrow dovetail slots in the 30s and I've yet to run across one that had one wider than 3/4. So just be careful in your explorations and you'll be fine.

Dan, interesting solution. Am I right to assume that the little piece of the spruce that is glued to the top of the dovetail breaks off along the grain and comes off still attached to the neck? I've never worked on one of these before.

That's usually what happens yes. It's a tiny little peninsula of wood so it usually comes off pretty well.

Thanks again - I'll stock up on razor blades!

Good luck, feel free to reach out if it's a bear. I've done 2 of those in the last year and they both had some challenges. But you're a smart guy so you can handle it I think.

Will do. I'm going to sort out the relief, put on new strings and then play it for a month, just to get a feel for how I'll want it to play. From that I can work out what I'll want to aim at with the reset. More in due course ....

What Dan said and thanks Dan. We do near exactly the same only we use the Stew Mac hook tool for cleaning out fret slots over a single edged razor blade. The Stew Mac fret saw that has two separate segments of fine teeth saw can be helpful too.

Additional info is why did Gibson do this put the top over the dovetail? Our forensic analysis indicates it was factory rework for some reason. We have looked for and found tell tales of the binding ledges being routed twice, once initially and a second time to remove the original top we think.

Lastly only a very small percentage of these are like this so it's uncommon but Gibson did produce these however they came to be from the 30's well into the 50's. We can remember resetting maybe half a dozen of them now over the years.

That's very helpful Hesh. I see no signs of rebinding, which makes me hope it's an uncovered dovetail.

I might take a piece of thin wire and bend a 1/16 hook on the end. Then, once the fretboard extension is included, I can slide it in and try to rotate it into the pocket. If I can, I'll get some idea of its exact location. If not, nothing lost.

Good news - the truss rod nut turns, and I have slackened the strings and the neck is *nearly* straight.

However, each clockwise tweak felt like I was at the end of the nut's travel. But waiting 10 mins, backing off and then tweaking a little further, moved it a fraction more without putting huge pressure on. I probably have 1/4 turn clockwise on it, and only two threads are showing.

Is this just the neck resisting? I suspect it has not been adjusted in decades. If so I'll keep going gently, giving it long rests in between.

My other options are:

1. Add a washer.

2. Clamp the neck into a tiny back bow, tighten nut, release clamps.

Any advice on which of these is best/safest? I'd like to get the neck dead flat under string tension, then back off gently until the relief is right for my playing.

Make sure the wood is not compressing from the nut tightening. It is always a good idea to add a washer if needed, and it is always a good idea to clamp the neck so you don't make the truss rod move the neck.

Also, before you started any of this, you should completely remove the nut and put a little grease on the threads.

Tenor guitars are so fun to play. I'd love to see pics of the old Gibson.

Of course! Plenty of good honest play wear and the usual minor scuffs and dings from actually being used to make music, but overall it's in decent condition.

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She's a cool old guitar. Yep what Barry said remove the nut all together and put some grease on the threads and put the nut back.

Now that you can straighten the neck you can lay a straight edge on the frets with the neck straight and see where the straight edge intersects the bridge and this will be able to definitively tell you if you need a neck reset.

Now back to square one. If this is not a covered dovetail an old Gibson is a decent guitar to do a first neck reset on. Hide glue, traditional assembly (if not a covered dovetail), etc.

Good luck to you Prof. Chris.

Thank you all. The neck is now straight, but I've detected a hairline sound board crack to fix before I put new strings on. It will get a neck reset soon, but it's playable (though hard work up the neck) so I shall spend a few weeks getting to know it first.

That will be a fun little tenor guitar to play when it's done.

New strings are on and have settled overnight so I can take some measurements:

Action at the 12th - 2.5mm bass, 2mm treble side (I think that's 5/64 and 4/64). There was quite a bow in the neck, as the bass side action was nearly 4mm before adjusting the truss rod.

Relief is around .010 (ten thousandths).

Before the strings went on a straight edge along the neck fell 3mm or 1/8 inch below the top of the bridge. The saddle is as low as it can go, around 1mm or 2/64 at the table side, but the strings all ring out nice and clearly. The intonation is really very good, except the low G rings a little flat at the 12th which is not unexpected. In due course I can improve that as there is a little room to compensate the new saddle when I make one.

The spruce bridge plate is in very good condition I'm pleased to say, very little chewing up from the string balls. The bridge was slotted from the factory and has unslotted ebony pins, so that seems to have helped preserve it.

What I've ended up with is very playable at the moment, though the action and the relief are both a little higher than I'd like. A neck reset is clearly called for, but I'm going to delay that for a couple of months and just play the hell out of it to get a feel for how I'd finally like it set up. Plus it's my new toy, can't have it sitting around silent just yet!

Cool - it's in need of a reset but not by much AND many people would be fine playing it as is because it's a tenor with fewer stings to overcome the higher action.

Now if I were setting this guitar up after the rod was adjusted, nut slots taken very low like we do I would set the action at around 4/64th" for the treble string and 4.5/64th" for the bass sting. So as you can see you are not far off and my bet is that I could squeeze a flatter neck and less relief out of her and get the action right where we want it. The nut slots too are likely too high, they always are....

So technically yes it's reset time when the straight edge is 1/8" below the bridge PROVIDED that when you used the straight edge the neck was near perfectly flat. But it's on the cusp so-to-speak and you are right to think that you should try her out for a while before deciding to go full on evasive and do major surgery.

Regarding the bridge plate this is a great example for you Chris of what I've been saying on this forum for years now unslotted pins save bridge plates! We had an 1867 Martin that we restored that had unslotted pins and there was zero bridge plate wear, zero.

Sounds like it's time to enjoy the guitar for a while.

You could surely squeeze a flatter neck - I'd be happy with a fair bit less relief than it has now, but I don't want to push the truss rod too far as I have no experience of what it feels when you've nearly but not quite tested it too far. I plan to add a washer or two and then turn it a little more (with backbow pressure to assist) once it's had time to acclimatise.

The nut is a pleasant surprise - when strings are held down between frets 2 and 3 the strings just kiss the top of fret 1. That's as low as I dare to go, though I've read your posts about gaining a fraction more here and can see your concept and technique.

Off to play it right now, in fact.

Oh, and one footnote if anyone else comes across one of these. The truss rod nut is not the standard Gibson 5/16 but rather 1/4. Fortunately the cavity is wide enough that a standard 1/4 inch socket will fit, if it's straight sided.

Very cool Chris. On the nut slot depth when we press and hold between the 2nd and 3rd we don't want the string touching the top of the first fret but ever so slightly off the top and that gap increases as the gauge of the string increases. If the string is in contact with the top of the first fret that is a string that very likely may buzz when plucked open. Clean open notes are the test of a slot being too low. To quantify our high e's are cut on a steel string with say 12's on it to be around .0005" above the first fret. It's not even easily measured and when we cut the slots we are simply looking for the precedence of absence of a sliver.... of light being visible between the string bottom and the fret top. Cutting nut slots this low is an art and very much a "feel" and "touch" thing. It also is a good idea to have plan B available when we cut a slot too low...... Our plan B is light cured dental fillings to build up the slot and even make it stronger than it originally was.

One last thing the neck may have been left in too much relief for too long and it may have taken a set. The neck should be capable of being adjusted into back bow when there are no strings on it. As for how tight to go with the truss rod nut I tighten pretty much all I can without going too far and to me that is about as firm as a very firm handshake. Not much of a metric I know, sorry wish I had a better idea of how to be more precise.

For academic purposes in this thread and because you are a Professor I wanted to bring up what happens if the neck has taken a set and is in some kind of permanent forward bow even to a minimal degree.

1). Heat pressing is a technique where the neck is put in back bow or what ever shape is desired to counter the ill, current shape and then gently heated over time and left in that heat over time to ever so slightly slip the fret board and other glue joints into submission.

There are special tools for this we have a heat press but prefer heat lamps and strategic placement, weighting, positioning, etc.

Does it work?

No not very well and we have rarely used it for some time now only using it as a last resort and with expectations of the remedy lasting more than a few months pretty low.

2) Refret where after all the original frets are removed the fret board is leveled eliminating the forward (or back bow) and then we take it further and mill relief in the proper amounts respectively for the bass and treble side in the board itself. Once fretted the board's relief translates to the fret tops for the most part and the leveling and shaping process with the new frets is minimal.

3). Creative fret dressing where to eliminate forward bow some frets 1-5 and 9-the last will likely be milled very low to reduce forward bow. I've taken frets to .015" and still had enough height to properly crown with a three corner, safed file.

4) Another thing we do with vintage instruments where invasive repairs are not suitable for a valuable vintage instrument is manipulate string gauges. Lighter gauge strings will reduce tension and eliminate some of the forward bow. Martin Silk and Steel would do this for you to some degree but you would lose to volume in the process.

So there are more remedies available for say forward bow if that's the case. I would avoid heat pressing unless you want to do it again next year and the next and the next...