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I posted this thread a few months ago viewtopic.php?f=10122&t=19744

Where basically I said I just glued on the fretboard and there was some backbow and I could only turn the truss rod(LMI double action) half a turn. Well I just strung it up and it still has some back bow and I still can only turn the truss rod half a turn. I haven't tried to really crank on it but it definitly will take some cranking to turn it or break something. I'm really not sure what could have happened to it. I just put a dab of super glue at each end and I glued the board on with fish glue and didn't spread glue over the shim; so it seems unlikely that the glue would have found it's way past the shim and back plate of the rod onto the threads. Any ideas of what I should do?

Also it seems with the guitar strung up the added tension hasn't helped to allow the truss rod to move counterclockwise either. Access is through the soundhole.

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Jeremy Douglas

I look at it this way - You have to be able to turn it, or you need to fix it. I use a 10" or 12" Crescent wrench to get leverage. I use the hole in the end of the wrench, not the normal end and stick the small end of the Allen wrench through that hole. While applying force to the neck in the direction you need it to move, give the truss rod a firm turn using the leverage from the Crescent wrench. Something is going to give, I'd bet on the threads turning, but you may break the truss rod. If you do break it, you'll learn all about making that fix.
You might want to wait for one of the more experienced guys to give a more reasonable response, but that's what I'd do. I get myself in all kinds of trouble!
Good luck!

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Any chance that when you glued the shim to the top of the flat bar on the rod that some glue made its way on to the thread on the back side of the rods nut? Also did you make sure the rod was in neutral position (no back or relief bow in the flat bar) when you glued all this up. If it really hard to turn 1/2 a full rotation the something is in a bind be it threads on the rod or the bar. If the rod is in true neutral position when installed I should take a bout 1/8 of a turn just to engage it to the bottom of the fret board with a tad of tension a half turn should not be that hard to turn. You would feel tension but so much you worried with cracking the neck or fretboard and you should have noticed movement in the neck around the 6th-9th fret positions.

Jeremy buddy how long has it been strung up?

The reason why I am asking is that it takes a while, at least a couple of weeks and sometimes longer for the neck to fully find it's natural position and some relief to set in.

I agree that the truss rod needs to work but it may be that some good old time will help the string tension bring the neck back and correct the back bow into something that works for you. Once it does you can decide what to do then if you don't have an range of adjustment that works for you.

I'm pretty sure I didn't get glue on the threads when I glued on the shim. The rod was in the neutral position when I glued everything up. I think something has to be bound up and probably glue on the threads or a defect. So what should I do, just try and turn it and see what happens like Steve said?

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Jeremy Douglas

Only about an hour.

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Jeremy Douglas

A couple of questions. Did you test the truss rod before you put it in the slot? Was the truss rod able to turn after you glued the fretboard on? You really need to make sure the truss rod works along each stage of building the neck.

Regardless of how you attached the fretboard, when you put the frets in or what glue you used, you still need the truss rod to work, otherwise there's no point in putting one in.

So, try cranking the truss rod and see what happens. It really shouldn't take much force to move the rod, but if you've got some glue (like you mention CA on the ends) on the threads it will take some force to break the hold of the glue.

If this doesn't work, there are two things you can do. First would be to apply pressure at the middle of the neck while clamping at the ends to induce some relief, also a good idea to do this under a heat lamp, which can help soften the glue (just a little bit) till the neck is straight. Log onto the MIMF to take a look at this thread with a good sketch http://www.mimf.com/library/neck_straightening3.htm

Next would be to pull the fretboard off, remove the spline and replace the truss rod. Glue the spline back on and then the fretboard.

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I would wait to see how much the string tension over time corrects the back bow. I am assuming that you don't have any carbon fiber rods in the neck either.

You can always do what ever you might do now later.

Thanks guys. Hesh, I already noticed some relief setting into the neck. It has relief but between the 9th and 14th frets the strings still lay on the frets. I guess I can wait a few days then see which way I should attempt to turn the rod.

Rod, I did test the truss rod to see if it works but I don't remember how far I turned it. It might have just been enough to see some bow form and then I might have quit since I was afraid to screw something up, I can't remember exactly. The rod would only turn the same amount after the fretboard was on, which is why I started that thread I posted the link to in my first post.

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Jeremy Douglas

I had an LMI TRSD that I put a little counter clockwise tension on to induce some relief when first strung up. Later when it settled in I couldn't get it back clockwise. I took the bolt on neck off and ran some penetrating oil down the threads at the soundhole end and let it sit a few hours. With some jiggling back and forth it released. I think sometimes during the building process some junk may find it's way into the threads at the south end. It's easier to work it with the neck off.
I usually cycle them fully and lubricate them at installation but now I add a drop of penetrating oil just before final neck installation and cycle again.
Good Luck
TJK

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Jeremy,If the threads have glue on them, a heated up trussrod should break it loose.Take a sodering iron and heat up the part you turn before turning the adjuster if you can get it there.If you have a soundhole adjustment, that might be hard to do unless you heat up the allen wrench with the iron before turning it.This is what i would try before forcing it loose.

Good news, I took a small deep well socket and extension to put on the end as leverage because the allen wrench that came with it has one long leg and one really short one and the only way it will reach is to stick the long end in the truss rod. So I gave it a little pressure and sure enough I got it to turn a bit more than another half turn. I didn't have to put a huge amount of torque on it but it was much harder to turn than it should be. It gave in little steps which makes me think it must be glue on the threads. It will turn back the other way freely now, at least to the previous stopping point. I can tell if I go further I will still have to put a good deal of pressure on it to bust up the glue.

Anyway I got it so it now has about .008" of relief at the 7th fret; plus it's sounding really good now. I'll let it settle for a few days and I've got to replace the plastic saddle I put in there with bone and set it up then hopefully I'll be good to go.

Disaster averted for now. Thanks everyone

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Jeremy Douglas

Cool, way to go Jeremy!

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