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I have a strange issue with one of my neck resets:

For some reason when I fit the neck the angle was right (a straight edge lands right on top of the bridge, and in one case a little above) but when I have the neck installed, refretted, and strung up, the action rose by quite a bit leading to high actions (over 3/32" with very low saddle) and a straight edge would land about 1/16" below the bridge...

What causes this and how to do I anticipate this change? Removing dovetail necks takes a bit of time compared to bolt ons.

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Cat-gut strings are made from kitten guts, stretched out to near breaking point and then hardened with grue saliva. As a result these give a feeling of Pain and anguish whenever played, and often end up playing themselves backwards as part of satanic rituals.

Typhoon Guitars
http://www.typhoon-guitars.com

Check how much the top rises under string tension and then allow for that when you calculate how much to move the neck. If you were touching with the straight edge without tension and the top raises say 1/16" you have to allow for that so the straight edge will need to be 1/16" above the bridge. Stewmac has a description of this http://www.stewmac.com/shop/Tools/Measuring_tools/Neck_Set_Gauge.html?tab=Instructions

Fred

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Fred Tellier
http://www.fetellierguitars.com
Facebook page http://www.facebook.com/pages/FE-Tellier-Guitars/163451547003866

I think I'm saying the same thing as Fred. When the guitar is strung up see where the straight edge hits the bridge and mark it, then detune and see where it hits. That distance is roughly how much you need to overshoot your neck set to get the angle you want.

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

Before regluing the neck you can actually just install the neck without glue and then string it up to test and then make any adjustments that are needed. You can use masking tape to hold the extension close to the body so it isn't flopping around. This way you can make sure things are right before gluing back. I have done a few that after I thought I had it right but the action was still high after I tested it.. Some old guitar just have rubber necks. I did a few harmony's and some other cheapies and many of these had poplar wood necks or no truss rods that would really flex under tension....Mike

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Another day, another dollar.

So does that mean I need to remove the neck again, reset it, and refret it all over again? I have already done this twice... this guitar is just rubber like.

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Cat-gut strings are made from kitten guts, stretched out to near breaking point and then hardened with grue saliva. As a result these give a feeling of Pain and anguish whenever played, and often end up playing themselves backwards as part of satanic rituals.

Typhoon Guitars
http://www.typhoon-guitars.com

Why would you need to refret it?

Anytime I remove the neck, and reset its angle a hump is created making the guitar unplayable unless the hump is planed out and refretted.

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Cat-gut strings are made from kitten guts, stretched out to near breaking point and then hardened with grue saliva. As a result these give a feeling of Pain and anguish whenever played, and often end up playing themselves backwards as part of satanic rituals.

Typhoon Guitars
http://www.typhoon-guitars.com

Instead of setting the neck to a given straightedge height at the bridge, measure the guitar before taking the neck off.
With the guitar strung up, measure the action and saddle height.
Remove the strings, then take a straightedge measurement at the bridge.
With this information, you can eliminate the variable of how much the guitar pulls under string tension.
The amount of change for the straightedge measurement at the bridge is equal to the change in saddle height, plus twice the change of the action at the 12th fret.
Add these two numbers to the straightedge measurement taken beforehand. This becomes what I call the 'desired straightedge' measurement. This is the measurement you want after the neck is reset, but before the strings are tensioned.
Depending on the guitar and the requested setup, the desired straightedge measurement may be even with the top of the bridge, or as much as 1/16" above it.

If it is unplayable, then it only occurs on the frets on the fretboard tongue. In this context, I dislike the term 'hump', because it implies that the neck has a rise that could potentially cause buzzing. But a neck reset does not generate that phenomenon, unless the neck is set too deeply into the dovetail. In other words, if the neck was straight before the neck reset, it will still be straight afterwards. 'Fretboard fallaway' is a more accurate description for a dropping fretboard tongue..
With this in mind, if you plane very much off the fingerboard in the dovetail area, you will reduce the straightedge measurement at the bridge, potentially resulting in an underset neck.
.

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John