Intonation

[TeleHawg]

I was having a hard time keeping my '56 Custom Shop Strat in tune. Checking with my tuner, I found that the G string registers as G when fretted at the 12th fret. But a second-fret A on the G string is close to Bb, and this sharpness continues up to the fifth fret.

I use Fender Super Bullet 10s, and my strings are pretty new. Since it's a '56 Relic, the frets are vintage specs.

Any ideas on what the problem is and what, if anything I can do to fix it?

[56telemike]

whenever I've had this problem it's a combination of...A) too light ga. of string...B) too tall fret...C) too much pressure...usually filing the slot on the nut down will help.

[jbmando]

Originally Posted by TeleHawg

I was having a hard time keeping my '56 Custom Shop Strat in tune. Checking with my tuner, I found that the G string registers as G when fretted at the 12th fret. But a second-fret A on the G string is close to Bb, and this sharpness continues up to the fifth fret.

My strings are pretty new. Any ideas on what the problem is and what, if anything I can do to fix it?

Fret the string at the third fret. There should be as little of a gap as possible and still be a gap, at the first fret while fretted at the third fret. If you have a lot of air between the string and the first fret, lower the nut slot. The problem is that you don't want to make the slot too wide, and most needle files are too thick for a G string slot. You might have to have a guitar tech or luthier do it. That is most definitely a cause of sharp intonation at the lower frets, and every string should be set up the same way. If you can't tell if there is a gap, hammer on the string with your index finger and you should hear the "plink" of the string hitting the fret.

[flyingbanana]

If there was a high fret in between the 12th fret and thesecond fret, wouldn't that make accurate intonation difficult? My thought would be to check for this before filing the nut....

[jbmando]

A high fret, if not fretting out when fretted at the second, should not affect intonation at all. I was assuming that a custom shop guitar would not have a fret issue. I can see a nut issue before a high fret.

[flyingbanana]

He said that it continues up toward the fifth fret. I wonder if that might be where the issue is at.

[thejerk]

I can't believe no one else has said this yet, but:

1. Check your relief-- too much can cause exactly this symptom. The higher frets are fine, but the lower frets have to be pressed too far which makes them sharp.

A quick truss adjustment would fix this.

2. If it isn't the relief, it is probably a nut that is too high. This will be more complicated, but manageable.

[still_fiddlin]

Besides too high action at the nut, if the string is not breaking exactly at the fb edge of the nut, you'll have intonation problems that are most noticeable at the lower frets. Check that the slot is cut wide enough that the string isn't binding, and that the nut itself isn't too high (i.e., a deep slot) to mask the problem.