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Well, been working on setting the neck of my OM. everything dry fits nicely, but I can't seem to get the truss rod to cooperate (flexes up out of the channel). It is clear to me that the upper plate (before the tone bar) is the pivot point. It absolutely blocks the truss rod going in, and if I do get it in, the truss rod deflects up out of the channel. What to do?

Also, it appears that the neck and fingerboard with truss rod are assembled separately from the guitar. How in the H E double hockey sticks does one get that whole mess back on (and in) the guitar body??

Mike

Hey Mike - Here is a pic that may help you even though this was a bolt on neck it is still done, fitting a slot in the top for the truss rod, the same way.

If you are using the infamous Popsicle brace (I use them but many don't) sometimes if it is located to far toward the top of the upper bout it needs to be relieved so the truss rod nut does not bind on it. Also be sure to dry assemble the neck to the body and using the proper truss rod wrench be sure that you can make truss rod adjustments.

It is kinda hard to visualize what you mean with the truss rod. My truss rods don't go beyond the neck block so no bracing is in the way except the access with a wrench. Could you post a picture? As for installing the neck with the rod installed, Hesh has shown the most common method.

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Thanks Hesh, I will "relieve" the popsicle stick. That is what I thought, just wanted to check. Hesh, what method is John speaking of?

Mike

PS: John, the Martin OM style I am building uses a longish truss rod that has to go through the tone bar (the adjusting nut). Its just the way it is. Getting that through the channel with a dove tail joint fully assembled looks almost impossible!

If you have the old style truss rod you have to cut the popsicle brace. This isn't a big deal. martin had been doing that for years. The new 2 way truss rod is different in that they don't really clear the neck block and you don't need to clear the top
john hall

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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

I think I may know the answer to my own question. Do I need to channel the TOP further back to the tone bar area? That will all be covered by the fret board anyways. I think Hesh's picture explained it after all. I have NO cut back in the top now. (other than that for the dovetail joint)

Mike

Here is another picture of what you had to do for the Martin style box section rod to clear. (Just like what Hesh showed and John mentioned)



The Martin head block has a cantilever support for the upper bout as part of the head block and had a groove for the truss rod and was notched for the popsicle brace. You just cut through that brace making the notch. I'd worry about doing that without the additional support.




Terry

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It's not what you don't know that hurts you, it's what you do know that's wrong.

Mike what John may be indicating is that since his truss rods don't venture beyond the neck block no relief of anything else is required. But I am guessing and John is the best one to answer that question.

What everyone else is saying here is my experience too. To relieve the Popsicle brace I use a round file, about 1/4" diameter, and carefully relieve a little and trial fit and repeat as needed. Be careful not to go so far in with the file as to gouge the upper transverse brace. It's pretty easy and I position the guitar body at eye level to help me keep the file in something close to the alignment of the truss rod.

Sorry to be a nag bout it's always a good idea once you are done and before gluing on the neck to be absolutely sure that with the truss rod wrench that there is no binding of the nut (truss rod nut that is) on the Popsicle brace and that the hole in the upper transverse brace aligns well with the truss rod.

BTW to make that extra slot in the top and I have to relieve my neck blocks too the Dremel small size sanding drums are excellent.

Ok, all, thanks. I do have the old style truss, and I did clear a channel back through the upper plate (popsicle). All is well.

Terry, could you please indicate the pattern of your rosette? (wbw, wtc, s for spruce). If you have the dimensions, that would be good too! Obviously, I can see the pattern, but not well enough to see if you have fine spruce circles involved.

Thanks.

Mike

John Hall,

Should I have recieved a fole pattern for drilling the tuner holes in the peghead? Can't seem to find info on that. It is an OM with 1 11/16" neck. Pretty standard stuff... but I am ready to drill those.

Mike

Mike,
The guitar in the picture was a Martin OM kit I built around 1998. The rosette was the one that came with the kit. It's just a standard D28 style that you can buy at the Martin 1833 shop or I'm sure John Hall has them as well. All plastic, no wood. Good luck.
Terry

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It's not what you don't know that hurts you, it's what you do know that's wrong.