Neck problem on a Martin 000-18

[Brad Elbein]

There's a young man--the son of a friend of mine--who wants to fix the neck of a mahogany Martin 000-18 guitar.  I volunteered to help, figuring I'd learn something.  (I'm in the middle of my second build, an octave mandolin.)  The crack in the neck doesn't look too terrible: 

 

I know the guitar probably isn't worth fixing, economically, but it will be a learning experience for him (and for me), so I thought I'd solicit help.  Does anyone know what the neck joint looks like?  Am I right that he's going to have to steam the joint and then shim it?  We can't tell anything about the action because this baby hasn't had strings for many a year.  Otherwise the guitar looks to be in excellent condition.  Many thanks in advance for your help.

[Paul Verticchio]

Thanks for that definitive info Stephen. You just saved the day(:

There's your cure Brad. I still suggest having an experienced repair person make those adjustments to make sure everything else "lines-up" correctly.

[Hesh Breakstone]

Neck resets are not a good place to gain experience when the guitar is a nicer one....  This one definitely would benefit from the job being done by an experienced sort - I agree with the crew here in this respect.  On the other hand..... ;)

The 15's are not very good guitars as far as Martins go and the neck joint is this very stupid glued mortise and tenon thing with one bolt to hold the glued joint together while it is curing - very poor design if it's what I believe it to be.

You can buy some time simply by tightening up the joint (single bolt under a square wood cover on the inside face of the neck block).  This will close up the gap at the heel.  But since this is a glued mortise and tenon the bolt has likely over time crushed the wood on the block and the glued tenon has obviously come unglued.

As such the proper way to do this is take the neck off, clean it all up, refit to specs (reset if needed)(meaning adjust the neck angle) and reassemble.  I would also recommend NOT reassembling as originally engineered since a glued mortise and tenon was an engineering mistake anyway and converting the neck to a two bolt bolt-on.  This requires adding another threaded insert, one more bolt, and countersinking the bolt head in the block face with a "blind" cutter or some sort that you could make too.  All in all not a simple or easy job....

The guitar's value is really it's utility and it's never going to be a collector's piece since they built so very many of these and they are not all that well put together when considering the neck joint.  I would pop the plate, tighten the bolt, restring and see what we have, does it needs a full reset, etc.  It may be that simply popping the cover on the face of the neck block and cranking the bolt will get you where you wanna go for now, but look for this to happen again if the joint is not reglued OR reengineered to something such as a two bolt system.

I've seen examples of 15 series that didn't last very long at all without lots of issues and the neck joint is a fairly common problem on these too.

[Brad Elbein]

Hesh!  You da man!  You told me exactly what I needed to know.  I was looking at that one bolt, thinking "OK, it COULD be a one bolt bolt on ... but naaaah, that doesn't make sense.  So it could be an adjustable truss rod, though where it's located it would be hard to adjust."  So now I know. 

Converting to a two bolt neck should not be difficult--I've done it before, though not on a guitar neck. 

I don't understand when you say "pop the plate," or refer to the "cover on the face of the neck block."  When you say "face," are you refering to the surface inside the body? 

[Paul Verticchio]

Brad,

You're right. Hesh is da man(:

May I make a suggestion?  If you had included the "I was looking at that one bolt, thinking "OK, it COULD be a one bolt bolt on ..." in your original post, you could have saved us all hours worth of response time and gotten your answer very quickly.

I encourage you, and all posters, to include "as much as you know, what you've observed and what you've attempted thus far and the results" when posting questions. That eliminates a lot of guesswork on our end which equates to time and that equates to $$. (sad but true)

As to the value of the guitar, well, if they paid $600 10 years ago, the got taken to the cleaners. That's an outrageous amount for a flyswatter!

In it's current state of disrepair, it's worth maybe $100 tops.  If fixed, these are currently fetching between $250-$300 in excellent condition.  The used instrument market is in the tank right now.  It's the best buyers' market that I've seen since the early '70's. 

As Hesh stated, they're not heirloom quality instruments, but if set up correctly and maintained properly, they can be excellent utility guitars.

Best of luck (:

[Hesh Breakstone]

Thanks Brad but this forum is the MAN..... ;) and everyone who preceded me in asking you questions made it easy to finally realize that it's a 15 series.  Paul is absolutely correct that we are only as good, on a good day.... as the info that we are presented with.

OK on the "face" of the neck block should be, or once was...., a square piece of wood with graphics on it, about 1 - 1.5" square that is held in place about as well as the glued mortise and tenon.... ;) with double sided tape....  Get in there with a single edged razor blade and try to carefully free this thing by inserting the razor blade between the neck block and the back of the wood plate.  Once it's out I always scrape the old double sided tape off and replace it with new tape.  You may have to do the same for the face of the neck block (what you see inside the sound hole when looking at the neck block) just to clean up the mating surface.

Please note:  Please do not cut yourself when working with the single edged razor or that would ruin my day knowing that I contributed to the injury of an aspiring Luthier. ;)  Not to mention what it might do to your hand too - please be careful and sorry in advance for being a nag....

Once the square cover is off and out you will see the bolt - it sounds like the cover may be missing or off already if you see the bolt now?  This is when you use the proper fitting Allen wrench and crank the bolt with the strings off until the gap in the heel closes up.  Easy peasy!  Again the better way would be to take the neck off and reengineer the joint but this will likely give you some years of service if not many more years of service and it can always be tightened again too.

Sting her up and see what you have.  Hopefully the action will be within an acceptable range with some tweaks and Bob's your uncle.

[Jeff Highland]

Gee Hesh,

Dont be so dismissive of the Martin neck joint, it's where all the tone comes from,,, they won't use no stinkin bolt on necks   lol

http://youtu.be/4Mbfd7OMq-M

[Brad Elbein]

Boy. That video is creepy.

[Paul Verticchio]

I'm with you Brad.

I bet Diane has another video extolling the virtues of their Formica series of instruments.  "You cannot visually tell the difference between Martin's Formica tops & backs & real wood.  And it sounds just as good, if not better".  What a CROCK!!!!!!

I love it when product nazis shoot themselves in the foot too.  At the beginning, it's all "ONLY a dovetail is good enough for Martin".  Later on it's "SO...we designed these instead".  And WTF is that e-dating crapola? And...not a single reference to Martins use of bolt on necks on many of their other instruments.

That whole video is just company propaganda designed to sell overpriced "common as oxygen" guitars to folks who are impressed by nothing more than the sales pitch of a witch-like caffeine junkie(: It was spooooooky!!!!

(-;

[Hesh Breakstone]

Yeah she said that the relationship between the neck and the body with a dovetail is like "e-dating..." 

This must be why Martin builds so very many dreads...... ;)  Not that there is anything wrong with d*eads.... mind you.... to each their own I say.....

Toward the end she also says that the joints, including the dovetail are proprietary to Martin..... yeah what you learn on YouTube - who knew that Martin invented the dovetail joint??? ;)

[Philip Warton]

At 1:54 she claims the neck gets strings prior to being "lovingly reunited" with its body. Interesting. I tried stringing up the guitar prior to final assembly and it never worked for me- but with practice I think I will get it. I came here to learn about fitting a neck joint, and, at too early a morning hour to handle it, have been  distracted by a crazy woman trying to sell me guitars....thanks for the laugh though.

[Brad Elbein]

Hesh:  I forgot to take a picture, but I can describe this.  Looking at an acute angle inside the sound hole toward the neck.  Up near the top--essentially just under the fret-board, where you'd expect a truss rod to connect--there's a small bolt with an allan head.  Below that, theres a block that runs down to the back, that appears to be the cover everyone's talking about. 

 

I assumed that the visible bolt--given its size and the allan-head--is in fact a truss rod.  Do these babies have adjustable truss rods?

[nathan clark]

Heres how I deal with that neck joint:

http://fingerlakesguitarrepair.com/martin-mortise-and-tenon-neck-re...