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I went to adjust a truss rod today on a guitar that is only about a year old. The truss rod is the kind from Allied. My Allen seemed to be turning with nothing happening so I got out my mirror and light to take a look. What I see on the inside of the end of the truss rod does not look like a keyway for an Allen wrench but threads! Could this be possible? Is the Allen wrench keyway a separate piece that gets threaded into the ends of the truss rod and, if so, do you think it's possible that somehow the one in this rod has come un-threaded and gone missing? More importantly, am I out of luck with this truss rod or is anyone aware of a fix? I tried to take a picture but I couldn't get a decent one that shows the threads I'm talking about. The camera wants to focus on the mirror and the objects in the mirror are out of focus.

Thanks,
Pat

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Set the camera manually to focus twice the distance between the lens and the mirror.

Hi Pat,
I was just prepping a neck for a rod, so I just checked the allen head adjuster and it does indeed come off. I see male threads with the nut removed. Should be able to find something to fit.

Brian

Edit. I just looked at allieds rod and it is different than mine, so that may not be correct.

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I just have a point and shoot camera so I can't do a manual focus. Never-the-less, I got a picture of the truss rod end which I think shows what I mean:



Do those look like threads? If so, I wonder if I can get the Allen wrench insert somewhere.

Pat

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I have never seen a rod like that. Who made the guitar, and can you ask them?

That looks like the back end of the rod. The adjustment nut is welded onto the rod and if it were missing you would see the male threads of the rod. The other end is the nut and therefore the female threads. At least that's the way the Allied rods that I have are built.

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Pat, That does seem quite odd. Going to the Allied web page they show their old and new rods but it doesn't appear there would be a round rod with threads inside. I originally thought the rod was put in backwards but that would be a square piece of metal with inside threads.
[url]
http://www.alliedlutherie.com/truss_rods.htm[/url]

I am not sure what you have there but it is clearly not right. Maybe someone else can recognize what it is.

Bob

It appears that the adjuster has been threaded all the way though instead of having an allen key recess formed on one end.
It is welded onto the rod end so you are stuck with it.
You may be able to thread a bolt into the end and secure it with permanent threadlock?
Perhaps ask allied for the tpi and dia

Looks to me as if the adjustor used on that rod missed out on the process of having one end milled for the wrench...

Looking at several of these rods that I have here in my stash the finish on the adjustor looks, well, unfinished compared to what I have here.

Might be a defective rod that clearly no one ever tested either since they can't, obviously. This is what happens when production parts skip a step or three...

If this one also did not miss out on another process the adjustor is welded to the rod and not removable.

Bummer

The good news is that it can still be adjusted with some creative coupling and basic hardware.

Great minds Jeff...

I made the guitar so I can tell you that the truss rod was from Allied. I'm really starting to think that these rods are made with a hex insert either threaded or force fitted into the end. Here's a close up of another rod I got in the same batch:



If you look closely, it appears, to me anyways, that the hex part is a different colour than the surrounding metal. So I'm thinking that somehow the hex fitting was lost from this rod. I always test the rods prior to installation so I'm sure I would have noticed if it came from the factory like this. I should be able to come up with something, but it probably means taking the neck off to get easy access to the rod end.

Pat

_________________
There are three kinds of people:

Those that make things happen,
those that watch things happen,
and those that wondered what happened.

If you knew what threads were on the end, you might be able to add an allen-head bolt with lock-tite-black.
Phone Allied on Monday. It looks like the factory installed a threaded joiner but Pat's photo looks like a hex-insert is added.

Bob

Pat to me it looks like the hex head shaft along with the threaded rod that it was welded to is missing. Could be that the rod was backed out to the point that where the threaded rod attaches to the truss rod broke and the whole assembly was backed out. Just added a hex head bolt would not fix anything because it needs to be attached to the rod. See where the threaded rod goes through the block. That's the block threads your looking at. I don't see a fix for that other than replacing the rod. At least that's the way I see it. Broke at red arrow

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you do have one option that may work A set screw will allow some adjustment. If you can figure out the thread , use JB weld and place that into the threads. If that doesn't work than you can pull things apart.

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John Hall
blues creek guitars
Authorized CF Martin Repair
Co President of ASIA
You Don't know what you don't know until you know it

The old Allied rods were a 10-32 thread. The rods are 3/16" and threaded on each end. The socket head is most likely tapped and threaded on before welding. Since the female thread is round my guess is that is the backside of the socket head still welded to the rod. Try threading a 10-32 screw into the end. If that works it's your choice on socket head or slotted for a screw driver.
Depending on the age of the rod it is possible it could be a left hand thread though it doesn't look like it from the picture. If that works attach as John said.

Thanks for the ideas, I'll try a 10-32 screw tomorrow.

Pat

_________________
There are three kinds of people:

Those that make things happen,
those that watch things happen,
and those that wondered what happened.

Tim I see what your saying now. So you think just the hex key insert is missing?

_________________
Beautiful and unusual tone woods at a reasonable price.
http://www.rctonewoods.com/RCT_Store
The Zootman
1109 Military Rd.
Kenmore, NY 14217
(716) 874-1498

It's possible that the hex seat could have sheared off. If you look at the picture that shows the hex seat there is material in the bottom from the broaching process that is folded over. The other side of that burr is the threads that screw onto the rod. If the broach is not centered in what is already a thin walled section it will weaken the hex seat, especially when it is heated during the welding or soldering process. The material can still be intact but have internal stresses that will shear under excessive pressure. The welding process is always a problem in thin walled sections as it can make the material brittle. One reason I am partial to the hex head turned by a socket wrench where the material can fill the hex and then be welded on.
Hope that makes sense.

Take a look at the hand made rods by Mark Blanchard for future builds. They are a work of art. On thing I have learned the hard way is that you really have to test these rods aggressively before installation using a jig like the one illustrated on the Allied web site. There were a bunch with bad welds a few years ago although I think that problem has been addressed.

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Pat
If the 10/32set screw will fit, you might try stud mount locktite( the red stuff). I will only release with heat, a lot of heat. and is a lot easier than JB weld to use.

Good luck
cecil

the best 2 ways I have found are the one Martin is using. The weak link is the silver solder or weld on the barrel nut . I have had these fail and will not use them ever again.
The Martin style is not welded on the threaded rod. That is where these fail , the heat changes the metal temper and they snap off. I have only made them fail through extreme abuse.

_________________
John Hall
blues creek guitars
Authorized CF Martin Repair
Co President of ASIA
You Don't know what you don't know until you know it

"The weak link is the solder or weld"

I agree it all comes down to the person or process doing the work. A good weld should be stronger than the material being welded and the material should fail first



Weld failures seems to be a common complaint. With all the failures over the years the the makers of the faulty rods could have gone to someone with a programmable automatic furnace with a conveyor belt feed. It would eliminate the problems but then the complaint would be the cost. Blanchards hand made rods are more expensive because he takes the time to silver solder them properly, and that is the reason they are better.

OK, so I took the neck off this morning (the second time for this guitar in the last week, I might add). Then I tried a 10-32 screw and it fit very nicely indeed. Even by making this a little tight I could work the rod in both directions. I'm off to Canadian Tire to get a screw with a hex head and some loctite. Thanks all for your thoughtful replies. Here's a picture of how it looks with the screw:



Cheers,
Pat

_________________
There are three kinds of people:

Those that make things happen,
those that watch things happen,
and those that wondered what happened.

That sucks Pat. John suggested JB weld instead of Locktite. i think that would be wise. I know this doesn't help at this point but Allied offers up a disclamer in regards to testing their rods.


Note graphic above: we do test the rods before we send them out. We have shipped many thousands of these with only a handful of problems. (In 2011 we did receive a bad batch, and there may be a few still floating around that we didn't catch.) We STRONGLY SUGGEST YOU TEST THE ROD before you install them. Make sure that you rotate the nut and not pry it when testing (or when adjusting). Give the rod a rigorous test. If the rod does break in the neck, all we can do is replace the rod; we cannot compensate for more than that. If you are able to "bury" the adjustment nut in the neck, i.e., allow access to the broach while containing the nut in the surrounding neck wood, prying is then prevented.
We suggest using a filler strip (mahogany for example) to prevent "rod rattle." This also takes up backlash in the rod.

A little off topic. I have about 50 allen wrenches from Allied that come with their rods. They don't fit. They are too small. You don't notice it so much if you test the rod on the bench. I have had the wrenches bind in the nut when adjusting the rod. I do try to pre bend the neck before adjusting but some of them fit so sloppy it doesn't matter. A friend ob mine went on a quest to find one that fit. They aren't in all stores but he found one and it was indeed an odd ball.

Another interesting question. JB Weld vs Loctite Red 271? I was leaning towards the Loctite because the threads seem to be a very close fit. If I thought there were some voids to fill I'd go with the JB Weld. Perhaps I'll buy both and do some testing.

Pat

_________________
There are three kinds of people:

Those that make things happen,
those that watch things happen,
and those that wondered what happened.