Hi Michael,
 I'm still fooling around with H575 no.2.

 I carved up the wood bridge and the intonation seems good at the 12th fret.

 I'm having some trouble with an open D chord sounding sour, so I started looking at intonation at the 3rd and 5th frets.

 I'm using a light guage 10-42 set of strings on this guitar and the low E, the A, the D and the hi E strings seem to voice accurately at the 3rd and 5th but the G and B strings pull sharp at those frets. (they align at the 12th and are intonated there.

 It doesn't look like there's much room to go down at the nut but I'm thinking that's what I'd have to try if I want to stop the strings from pulling sharp.

 I guess it was better with the fatter strings? I didn't check, but H575 no.1 has fatter strings and seems to work well. That doesn't really prove anything but maybe it illustrates it.



 Anyways... any thoughts? What would you do? Lower the two slots in the nut?

 I tried tuning the strings a little flat... but then they voice flat both open and down near the 12th fret... so that doesn't seem like a good work around.


 Thanks for any ideas you may share.



 best regards,
mike

 

If the strings are high at the nut they can pull the first couple of fretted notes sharp.

"High" is subjective. You stated "it doesn't look" -  Mike I like measure.

If you can't set up a dial indicator then try to use feeler gauge to check each string.
There is a rather broad range that suits players but there should be close relation to each graduating- most commonly
low to high from 1st to 6th.

How to measure: press string down between the 2nd a 3rd frets and measure the gap between the string and first fret.
For example my last set-up I set .015 for 1-3 .018 for 4 and .020 for 5,6. Note- these are players preference.

The first check I would make is at the nut. The slot should slope - high side on fretboard side towards the tuners.
Measure all strings for nut height.

Let me know what you find.

Some luthiers recommend that the nut slot angle should support the string for the full width of the nut. Some think that
a small "ledge" and then slope down so string doesn't touch. I don't see an advantage with the latter but I do see a disadvantage in
that the nut can wear faster.

Of course the issue can be a combination of both- slope and height. 

The nut slot width should also be checked. A string should glide through the slot with NO binding.
Easy checks:
Lift the string and listen for a click. Turn the tuner and listen for a click or pop. ( my fav is to push down on the string inbetween the
nut and tuner...it should return to pitch when released.)

Thanks Michael!

I'm working on "patterns" today and will get back to this when I get my feeler gauges out.

I've avoided them because they still seem to need the use of my younger eyes... and I can't find those any more.

Might be time for a dial guage. :-)

This is what I use. Press down between second and third fret- zero gauge or remember reading and press string down to contact first fret. Great tool.

I figured that was what you were referring to in your previous post.

I pulled out my feeler gauges and then I went and put one of those in the shopping cart earlier this morning.

I've been wondering if they were nice to use. I figured if you had one they must be. :-)

I guess I should get a capo too.


Thanks.


best regards,
mike

Added it to my wish list. Thanks for the info.

You're welcome Geoff.

I searched just to see what instructions may be given - as with many things there
are different ways.

I will say that one should be very careful in choosing what instructions to follow LOL.

Here is one that I thought was funny:

Measuring nut action
Here you need a set of feeler gauges (the thin metal strips that are used for gauging the size of a gap. These can be obtained from any auto-supply or hardware store.
Fret the string at the first fret and slide a feeler gauge between the string and the fingerboard, right in front (body-side) of the fret. If the feeler gauge is loose, try progressively thicker gauges, until a snug fit is found. Not too tight however - the gauge can push up the string slightly, but not too much. You may need to use a combination of different gauges to get the exact height.
When you have the correct gauge, this should be a near perfect indication of how high the string is from the fretboard at the first fret when fretted. This should be almost identical to the height of the fret and also the perfect height for the nut slots.

Do Not Follow that! LOL    "Almost" and "identical height to the fret being perfect height for the nut slots"  !! That's NUTS.

One issue I had when making the nuts for the builds I did for ones that couldn't "test" play the instrument was to "guess". I didn't like guessing but hoped by doing so that they wouldn't have to take the guitar in for adjustment. A big risk I took for low playing action for them. The reason it was a risk is because they really didn't have much room, if any, to lower the nut action. If it was to low for them the nut would need to be replaced. High nut action for some is just uncomfortable and may also cause intonation issues so it's something I'd sure prefer to set for another "in person".

Nut action changes may require (and probably will) checking other points of a set-up such as relief, string height and intonation (saddle adj.)

Somewhat of an easy thing to do but done wrong and major problems.
Now I don't see having a nut replaced a big deal but it may not be so easy for others.

If there were issues that required attention they've been silent and probably out of kindness.

My G and B string seem to lower than 0.015 when measured as described.

The Dial indicator is on the way. :-)

mike_mccue


My G and B string seem to lower than 0.015 when measured as described.

The Dial indicator is on the way. :-)

I would rule out slot height being the issue for them playing sharp.
 
I would assume if the nut was tilted it would effect all strings- so did you make sure
the slots for G/B were slanted correctly ?( highest point being fretboard side)

Not yet.

In the past I've endeavored to have the slots fall away so that the contact patch is minimal and serves as an edge.

I'll have to take a look at this nut.

I may also try a more traditional set of strings for this particular guitar.

It was probably set up at the factory for a wound G and I went and put a set of "skinny" 10-42 Rickenbacker compressed-rounds to see what would happen.

I like the tone of the guitar with them but it may not be the right set for the guitar.


Thanks for continuing to consider the questions.


best regards,
mike