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Old 04-08-2020, 06:39 AM
Runepune Runepune is offline
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Default Straightening a neck with too much relief

How much work (costly) is it for a luthier to straighten excessive neck relief?

The neck is otherwise straight and the guitar is in perfect shape. I do love that it has an enormous amount of dynamic power due to the high action across its length...However, it's just a bit too much.

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Old 04-08-2020, 07:42 AM
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The process would likely be a heat press. Some variables involved.....sometimes frets can pop up and you'd need a reseat/reglue, dress and level.

I'd guess between 150 and 250, but again, it's hard to say.
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Old 04-08-2020, 08:04 AM
MC5C MC5C is offline
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Heat press is indeed one way, but controversial in some circles (Like the internet... :0 ). It depends on heat and pressure to slip the glue joint between the fretboard and the neck (if the glue used can be "slipped") or simply uses heat to facilitate bending the neck until it's straight again. Reports vary between "it worked for 20 years for me" to "it lasted 6 months".

Another way to deal with it (not one I particularly favor) is to de-fret, plane/sand the fretboard straight (not the neck) and re-fret. Thins the fretboard at both ends, which may or may not be a serious issue, but has the advantage of leaving the neck in the place it's decided it wants to be. Might have visual problems, or structural problems, if too much needs to come off the fretboard.

Most drastic, and probably best solution mechanically, would be to remove the fretboard, heat/press the neck straight, install a truss rod to stiffen the neck and hold it in place (could be an adjustable truss rod, or an aluminium/carbon fiber insert) and replace the fretboard. If it was mine, I'd try the first method first, heat/bend/slip the neck into place and see what happens. You lose nothing by trying that way first (except a couple of bucks).
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Old 04-08-2020, 08:07 AM
charles Tauber charles Tauber is offline
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Depending upon the situation, the least invasive might be compression fretting.
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Old 04-08-2020, 08:52 AM
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Truss rod adjustment if it has one. Takes about 5 minutes.
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Old 04-08-2020, 09:48 AM
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Quote:
Originally Posted by TBman View Post
Truss rod adjustment if it has one. Takes about 5 minutes.
Not that many classicals do
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Old 04-08-2020, 09:21 PM
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Quote:
Originally Posted by charles Tauber View Post
Depending upon the situation, the least invasive might be compression fretting.
My first thought as well. How much extra relief is there? Pretty easy to put a classical neck into back-bow territory via fretting, IME.
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Old 04-09-2020, 03:55 AM
Runepune Runepune is offline
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Thanks, all! Many options. Never even heard of compression fretting. The guitar is not a very expensive one, but it's worth much more than it cost me...as it sounds better than its price
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Old 04-09-2020, 03:19 PM
charles Tauber charles Tauber is offline
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Quote:
Originally Posted by Runepune View Post
Never even heard of compression fretting.
Guitars have frets that are inserted into slots cut into the fingerboard. Modern frets are "T" shaped and comprised of a "tang" embedded in the slot, which you don't see, except on the ends, if not concealed, and the "crown", which is the more-or-less semi-circular part of the fret that you see and against which the strings are depressed.

The width of the slots are carefully sized to grip the sides of the tang. (Common slots sizes are .021".) If the tang is too thick relative to the slot, the tang wedges the slot "open". If done on several or more frets, the result is that the fingerboard, and neck to which the fingerboard is attached, is bent backwards, creating less relief/neck bow. One controls how much backwards bend occurs by the relative size of the tangs and slots and how many, and where, the oversized-tang frets are placed.

The process is referred to as "compression fretting", and is sometimes used to reduce the amount of forward bow/relief in a neck that doesn't have a functional adjustable truss rod.

Classical guitars usually have higher string action and greater relief than steel string guitars. While too much relief can occur in classical guitars, it isn't particularly common.
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Old 04-10-2020, 03:22 AM
Runepune Runepune is offline
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Quote:
Originally Posted by charles Tauber View Post
Guitars have frets that are inserted into slots cut into the fingerboard. Modern frets are "T" shaped and comprised of a "tang" embedded in the slot, which you don't see, except on the ends, if not concealed, and the "crown", which is the more-or-less semi-circular part of the fret that you see and against which the strings are depressed.

The width of the slots are carefully sized to grip the sides of the tang. (Common slots sizes are .021".) If the tang is too thick relative to the slot, the tang wedges the slot "open". If done on several or more frets, the result is that the fingerboard, and neck to which the fingerboard is attached, is bent backwards, creating less relief/neck bow. One controls how much backwards bend occurs by the relative size of the tangs and slots and how many, and where, the oversized-tang frets are placed.

The process is referred to as "compression fretting", and is sometimes used to reduce the amount of forward bow/relief in a neck that doesn't have a functional adjustable truss rod.

Classical guitars usually have higher string action and greater relief than steel string guitars. While too much relief can occur in classical guitars, it isn't particularly common.
Thanks, Charles
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