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PostPosted: Mon Sep 12, 2022 4:30 pm 
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Koa
Koa

Joined: Fri Feb 10, 2017 11:09 pm
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Location: Cowichan Valley, BC, Canada
First name: Conor
Last Name: Searl
City: Duncan
State: British Columbia
Zip/Postal Code: V9L 2E5
Country: Canada
Status: Semi-pro
I have a 2012 Music Man John Petrucci guitar in the shop that just moved out here to the west coast of Canada from the prairies. This is about as big a change in environment as a guitar will typically ever experience, and this is likely where my problem is stemming from. The guitar is of a high quality and as far as my experience counts for anything, Music man makes a consistent and reliable product.

It appears that there is a hump around the 3-4 fret, and then excessive bow in the middle of the neck. The problem seems pronounced when using the string as a straight edge, with a notched straight edge the problem is less extreme. The truss rod seems to work fine, it moves smoothly and predictably. When I back the truss rod all the way off without any strings on the guitar I get a lot of relief and the curve seems consistent. When I tighten the rod, the neck straightens out but frets 1-4 dive backwards, it's behaving almost as if there's a hinge in the wood at around the 4th fret. Is it possible that the change in humidity would have introduced such an odd hump at around fret 4/5, and that it would cause this?

The frets are stainless steel, there is very little wear and the fret work is impeccable. I suspect a dressing is in order. I just feel really stumped by how this neck is behaving.


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PostPosted: Mon Sep 12, 2022 7:50 pm 
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Brazilian Rosewood
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Location: The Woodlands, Texas
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I worked on a neck that reacted strangely when under tension. It turned out to be a grain irregularity that caused the neck to twist when strings and truss rod were brought up to tension. The cure was to level the neck under simulated string tension. This guitar was the encouragement I needed for making a string simulation jig using Teeter's design.


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PostPosted: Mon Sep 12, 2022 7:54 pm 
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Koa
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First name: Bob
Last Name: Gramann
City: Fredericksburg
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Country: USA
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If it has only recently changed environments, it might be worth letting it settle in the new one for a few weeks before doing anything major.



These users thanked the author bobgramann for the post (total 3): Conor_Searl (Wed Sep 14, 2022 11:58 am) • gxs (Tue Sep 13, 2022 5:22 pm) • Chris Pile (Mon Sep 12, 2022 9:18 pm)
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PostPosted: Mon Sep 12, 2022 9:20 pm 
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First name: Chris
Last Name: Pile
City: Wichita
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Quote:
If it has only recently changed environments, it might be worth letting it settle in the new one for a few weeks before doing anything major.


Wise words from Bob, but I'm betting the some of the wood has gone bye-bye. Time will tell, and then - plane the fingerboard.

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PostPosted: Tue Sep 13, 2022 2:00 am 
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Old Growth Brazilian Rosewood
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Yep let it hang for a week or two before you do anything and a fret dress is in order provided that you really cranked the rod and tried to completely straighten the neck with the rod first. It's a bit of an S curve and they usually go away if the rod has enough travel and impact. If you can't get it straight and I think you said that above indeed a fret dress is in order and it will be a bit of a tough one because of the stainless frets.

I hear ya on it's strange to see this on a Music Man. I have a very premium Strat type guitar that I bought last year with a roasted neck and stainless. The neck is moving every several days and I have to adjust the set-up near weekly and it lives in constant 45% RH 72F.... I'm not pleased and if you noticed I am not indicating the maker. But lousy necks can be found on anything, sadly.

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These users thanked the author Hesh for the post: Conor_Searl (Wed Sep 14, 2022 11:57 am)
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PostPosted: Tue Sep 13, 2022 7:19 am 
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Conor, one trick I've tried that works some of the time.... tighten the truss rod all the way, and then leave it for a day. Then loosen it all the way, and leave it for a day. Repeat several times until the kink relaxes (hopefully).

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These users thanked the author Chris Pile for the post (total 2): dzsmith (Sat Sep 17, 2022 9:46 am) • Conor_Searl (Wed Sep 14, 2022 11:57 am)
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PostPosted: Thu Oct 20, 2022 5:58 pm 
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Mahogany
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since this is a music man, the neck is probably quartersawn. when using quartersawn if the grain isnt perfectly parallel to the side or is cut at a diagonal ( so the grain kinda runs from one corner to the opposite) the wood can develop a "hump" if the wood hasnt been properly aged or dried. this can happen in perfectly flatsawn wood as well. who knows though? if the instrument was purchased new, the end user should be able to obtain an RA and have music man look at it and see if it is something covered under warranty! good luck!



These users thanked the author Lou Thier for the post: Conor_Searl (Mon Nov 14, 2022 12:42 pm)
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PostPosted: Mon Nov 14, 2022 12:44 pm 
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Koa
Koa

Joined: Fri Feb 10, 2017 11:09 pm
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Location: Cowichan Valley, BC, Canada
First name: Conor
Last Name: Searl
City: Duncan
State: British Columbia
Zip/Postal Code: V9L 2E5
Country: Canada
Status: Semi-pro
Lou Thier wrote:
since this is a music man, the neck is probably quartersawn. when using quartersawn if the grain isnt perfectly parallel to the side or is cut at a diagonal ( so the grain kinda runs from one corner to the opposite) the wood can develop a "hump" if the wood hasnt been properly aged or dried. this can happen in perfectly flatsawn wood as well. who knows though? if the instrument was purchased new, the end user should be able to obtain an RA and have music man look at it and see if it is something covered under warranty! good luck!


Thanks man, perhaps that was the reason. I hung the guitar for a few weeks, moving the truss rod back and forth twice a day, it removed some of the hump, but not all of it. I ended up dressing the frets, and have a happy customer.



These users thanked the author Conor_Searl for the post: Chris Pile (Mon Nov 14, 2022 2:11 pm)
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PostPosted: Mon Nov 14, 2022 2:11 pm 
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Patience wins the day!

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