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  #1  
Old 09-24-2020, 08:19 AM
Bobd Bobd is offline
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Default Truss rod adjustments: how much is too much

I just received a Guild OM-240ce yesterday. Love the sound of this guitar but the action was really high. I looked up how to lower it and found that a truss rod adjustment can help.

The instructions were to first try to loosen it to be sure it was already tightened all the way. When I did this there was no resistance at all. So I then started to turn it an 1/8 of a turn at a time. The first 2 turns gave no resistance as if it was not engaged at all. The 3rd turn I finally felt some resistance. Measured the height at the 12th fret and it was 3.5mm. Re-tuned and then another 1/8 turn. I did this about 4 times until the measurement at 12th fret is about 2mm. It still seems a little high to me.

So, how far can I go with the truss rod? should I adjust until there is fret buzz and then back off? Or is 2mm a standard height and I should just leave as is?
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Old 09-24-2020, 09:44 AM
Wooly Wooly is offline
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Truss rods aren't meant for adjusting action. They will effect action to a degree but are used to adjust relief. (Back or forward bow in the neck). If you want to lower the action, generally the bottom of the saddle needs sanding but there is a formula and method for that also. Over tightening of the truss rod can break it. Then you've got a problem.

I would suggest taking it to a guitar tech and let him/her check it out. 2mm is about right for the low E depending on what you like.
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Last edited by Wooly; 09-24-2020 at 09:52 AM.
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  #3  
Old 09-24-2020, 09:51 AM
Bobd Bobd is offline
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Hopefully I didn't over tightened it. It was completely loose when I started. By the time I made the last turn it was still very easy to turn and it did lower the action about 1.5 mm's.
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Old 09-24-2020, 09:55 AM
Wooly Wooly is offline
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It shouldn't be fully tightened but there again, truss rods aren't meant for adjusting action.
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Larrivee OM-03
Seagull SWS Maritime Mini Jumbo
Alvarez AP70SB Parlor
Alvarez AF60SHB
Seagull Concert Hall Mahogany
Harmony H1215. 1953
An 80 year old Kay (approx)
Epiphone ES-339
Epiphone Les Paul 50's Standard
3 home built Strat's
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  #5  
Old 09-24-2020, 10:06 AM
Piercast Piercast is offline
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Quote:
Originally Posted by Wooly View Post
Truss rods aren't meant for adjusting action. They will effect action to a degree but are used to adjust relief. (Back or forward bow in the neck). If you want to lower the action, generally the bottom of the saddle needs sanding but there is a formula and method for that also. Over tightening of the truss rod can break it. Then you've got a problem.

I would suggest taking it to a guitar tech and let him/her check it out. 2mm is about right for the low E depending on what you like.

^^This^^ is absolutely right.
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  #6  
Old 09-24-2020, 10:22 AM
archerscreek archerscreek is offline
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What has worked for me is first I put the same gauge strings on the guitar/instrument that I intend to play it with. Then I let the instrument acclimate to those strings and its environment for a few days.

Once it is settled in, if there is too much relief in the neck I will adjust the truss rod in small increments. I allow the instrument to get acclimated to each adjustment before doing more adjusting. For me, the little by little process can occur over multiple days. Sometimes I tweak things so slightly and let the instrument settle in so much that it might take a few weeks before it is as perfect as I want.

Which brings me to your question. Too much or too far is when you tighten the rod so much that it overshoots the ideal bow/relief in the neck and causes the neck to bow in the opposite direction and the strings to buzz against the middle frets while being fine on the upper or lower frets.

In my experience, when an instrument has been neglected as far as proper truss rod adjustment is concerned, I know IÂ’m not going to get the rod properly settled in on day one.
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  #7  
Old 09-24-2020, 11:24 AM
Bobd Bobd is offline
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It seems to play much better since I did the adjustment. It's easier to play all over the neck and there is no string buzz anywhere. Could it just have been that the neck was bowing away from the strings?
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Old 09-24-2020, 03:45 PM
HarryQ HarryQ is offline
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If there is excess relief in the neck, reducing or eliminating the relief by adjusting the truss rod can indeed lower the action. So it can be, in fact, one component in reducing the string height, along with saddle and nut adjustment where appropriate.
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Old 09-24-2020, 04:37 PM
MThomson MThomson is offline
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There is lots of information at http://frets.com/FretsPages/pagelist.html including on setting up your guitar.

Long story short, action is adjusted by

1. Setting neck relief using the truss rod
2. Adjusting the string height at the nut
3. Adjusting the saddle height
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  #10  
Old 09-24-2020, 06:41 PM
bobhowell bobhowell is offline
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what relief do you measure in the neck
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  #11  
Old 09-24-2020, 07:51 PM
tadol tadol is offline
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Quote:
Originally Posted by MThomson View Post
There is lots of information at http://frets.com/FretsPages/pagelist.html including on setting up your guitar.

Long story short, action is adjusted by

1. Setting neck relief using the truss rod
2. Adjusting the string height at the nut
3. Adjusting the saddle height
Exactly right! But add

4. If it still don’t work, take it to an expert - it may need a neck re-set -
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