Narrow nut channel for truss rod

**BCox** · Mar-02-2021, 7:02pm

Hello,

I am trying to get my mandolin set up after the saddle on the bridge broke. It is a Flatiron Festival F5 made by Gibson in 2000 in Nashville. The luthier who is setting it up called me today and said that he was having a hard time getting to the truss rod nut. He said the pocket was too narrow for the tools he has. I asked him if he had on that fit a Gibson and he said he tried, no luck. He said the pocket was so tight he doubted if he could make a socket with enough wall to work. I told him I will search out an answer if I could. So here I am. My question is where can I find the appropriate tool and has anyone run into this problem before. The mandolin was made by Gibson in Nashville and I have always been told that they are basically the same as a Gibson F5G, so I was shocked that the truss rod nut pocket was different sized. Any suggestions would be helpful.

Thank You

**poul hansen** · Mar-02-2021, 7:43pm

If you can get the TR nut out, maybe you could use StewMacs TR rescue tool, that contains a drillbit which can drill the wood around the trussrod.

https://www.stewmac.com/video-and-id...tructions.html

**pops1** · Mar-02-2021, 8:27pm

I use a nut driver for a narrower socket. It's thinner than a socket. I have ground sockets down thinner for specific tasks tho and that may be an alternative.

**j. condino** · Mar-02-2021, 9:01pm

Find another luthier immediately! This is not a complicated task....

**sunburst** · Mar-02-2021, 10:22pm

A serious pet peeve of mine!
You decide a truss rod needs to be adjusted, should take a couple of minutes, tops. Instead you spend half a day trying to find a tool to fit the poorly though out and poorly made truss rod situation. Instead of a quick and easy set-up step, you either have to waste the customer's money of loose money just trying to adjust the truss rod.
We've been over this before on here.
When I encounter this I remove some wood to make way for a tool to make the adjustment. Some people think that is a horrible thing to do, but if the darned thing was done right in the first place the wood would already be gone so that there would be room to work!

**Richard500** · Mar-03-2021, 9:40am

Might be worth mentioning that the pocket could have been correct, but that the nut can be various diameters, so it’s possible the original one was replaced at some point with a wider one. Even so, if what’s there is one of these long nuts with a cone taper on the outboard side, it should be removable without even getting a socket around it - unless it’s wrong thread, crossthreaded, or corroded. However, someone stymied by the removal issue probably shouldn’t be trusted with the adjustment subsequent.

**Tom Haywood** · Mar-03-2021, 10:14am

Been there myself. Thin walled socket, thin walled nut driver, Gibson or other truss rod wrench, or whatever you have that works without boogering up the nut. Sometimes nothing will fit, showing that the manufacturer had their own special tool for the job (Gibson!). Sometimes it is not just the shallow depth of the wood around the nut, but also that the pocket is too short to get a straight tool (such as a standard length short socket or nut driver) to the nut. Sometimes the excess rod is too long for for a standard nut wrench to reach the nut. One way or another, there goes your entire fee for a set up. It is a major pet peeve of mine, too.

Calling the customer about concerns at this point seems completely reasonable to me. In some cases you do have to take out some wood at the most vulnerable place on the mandolin. That is not part of a "standard" set up, and the luthier may feel that full disclosure is in order. Taking out wood or making a new tool requires added time and skill. The luthier may not feel comfortable with that, or he may be indicating that the fee needs to be higher. I recall that some of the Gibson Festival mandolins are very small in the truss rod nut area. If that's true with this one, I wouldn't fault a luthier for being extra cautious or not wanting to do the job at all.

**poul hansen** · Mar-03-2021, 10:33am

Have you checked if there is an additional allan/hexkey hole in the top of the nut?

**Jeff Mando** · Mar-03-2021, 12:11pm

I agree with John, sometimes I have to remove a little wood to get a tool in there. I have a tiny 3mm (approx 1/8") blade chisel that is great for this. It is razor sharp and just "shaves" away the right amount of wood.....also useful for saddle slots, nut slots, inlay work, etc....

**rcc56** · Mar-03-2021, 12:34pm

I've seen pockets that were so small that I wondered how the factory ever got the nut on in the first place.

If a tool can't be found, one can be modified. If that won't work, you've got a problem.

If you think you have to remove wood, cease and desist, let it sit for a day, then take a second look. If it is necessary to proceed, be extra careful, make sure you have the right tool for the job, make sure it is extra sharp, and take only one stroke at a time.

**Richard500** · Mar-03-2021, 12:48pm

Right: used to be American assembly workers put in sheet metal screws in cars and appliances by hammering. Carpenters in a boom area where I lived would put heat register cutouts in floors with an axe. How many truss rod nuts an hour coming down the line?
Anyway, if it’s possibly useful, add a set of cork stopper borers to the kit. These are things you might have seen in high school chemistry class; a nested set of many diameters of thin-wall hollow tubes with inside bevels. Plus the interesting sharpener that comes with them.

**sunburst** · Mar-03-2021, 2:06pm

Originally Posted by rcc56

...pockets that were so small that I wondered how the factory ever got the nut on in the first place...

Undoubtedly some of them were installed with the nut already threaded on. There is no way it was screwed on there after the thing was assembled. Sometimes it's hard to really care about your factory job, especially when you have to assemble a bad design.

**rcc56** · Mar-03-2021, 4:59pm

Oh. It thought it was Murphy's magic manufacturing gremlins that installed those nuts. Those ignominious little devils will work cheap enough to satisfy even a deposed manufacturing mogul like H.J.

**Dale Ludewig** · Mar-03-2021, 6:29pm

I think John has it. The truss rod nut and washer were put on when it was glued in. I've done it to myself on occasion. So I have learned how to deal with it afterwards. First comes the dope slap on your forehead. Then the curved gouge. Then the ground down nut driver.

**MrMoe** · Mar-03-2021, 7:00pm

Much of this thread reminds me of one a few weeks ago regarding which truss rod is best. The TRMT and similar ones from LMI continue to look very sensible to me.

**Lbartosh** · Mar-04-2021, 10:25am

I just went thru this on an old epiphone, very tight opening for a 7mm nut. I ended up cutting a small amount of wood away from the sides. Just cut a tiny bit away mainly from the overlay. The truss rod cover was still much larger so there was no physical damage. I found that a 12 point 7mm box end wrench did the job just fine.