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I know I have read this here before but can't find it, and I was still confused after reading it anyway;

On a classical with no truss rod, I thought you were supposed to sand a small amount of relief into the fingerboard before fretting. So how does leveling the frets not sand away that relief? Are we relying then on the string tension to pull relief into the neck? And if so, why bother sanding the relief in there in the first place?

You do not level the frets. Glue some sand paper, such as 400 grit wet dry, onto a flexible bit of wood, similar to some lathe or thinner--say six inches long. Paint the frets with a magic marker so you can see if you are striking off the top of each fret. Move the sand paper over the frets with the lathe oriented along the long way of the fingerboard, following the contour of the relief, which the lathe will do more or less automatically.

Some of us sand a taper on the finger board -- in other words the FB is thicker at the nut end than it is at the sound hole end, so the fret board plane is still flat. So if you are talking about relief in the context of having the neck with a slight bow -- no, I do not do that ---- straight works fine with the FB taper strategy. Others tip (set the neck angle) with the head-stock end up toward the sound hole (opposite of the steel steel design strategy). I don't do that either.

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Ken Cierp

http://www.kennethmichaelguitars.com/

Thanks for your answers to my dumb question. I just looked at the instructions that I used to follow and realized that I had misunderstood something. I will see if I can edit this and delete.

Turns out that the instructions I used to follow were stating to sand a small relief into the neck to make up for the back bow introduced from fretting. I no longer do sand relief into the neck and now fret on an uncarved neck for more support to prevent back bow. I can't figure out how to delete this topic so I thought I might as well explain.

You were right the first time. A small amount of relief (generally around the 7th fret) can give a "softer action" on a classical. The wider excursion of the nylon strings benefit from this and the overall string height can be lowered if there is a small amount of relief.
Try "leveling" the frets with a shorter length tool and checking with a longer straight edge to see where to make adjustments to create or preserve the relief.

The relief is often sanded into the bass side without doing the same on the treble. This allows for more vertical string travel for the heavier bass strings. Its a small amount, a 1/2 mm or so, largest around the 9th fret or so and tapering to around nothing at the 5th and 12th. This is not to compensate for backbow, it is prompted by setup considerations.

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Jim Kirby
kirby@udel.edu

So Clay, how short a leveling bar do you use when leveling frets? And Jim, do you level with a shorter tool as well? I was just getting ready to order a new long leveling bar so maybe I should be looking at a different option?

Wendy, a way that David Schramm shows to do that is to secure your guitar to the work surface and hang a small weight (I think it was around 5 pounds) from the headstock both when you level the fretboard and when you level the frets. When the weight is removed the neck "springs" back and results in relief in the correct area. I did this on my first and it worked, simple and effective! Since then, I just go for a dead flat fretboard and dead flat fret leveling with no problems of buzzing, but I know some classical players do want a little relief in the neck (they must play far more aggressively than I do,)
Mike

If you level frets with no tension on the guitar, you'll get relief when you string it up. I do put a little on the bass side in addition to what comes naturally, though. I'm not really sure any artificial relief is absolutely necessary, though.

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Waddy

Photobucket Build Album Library

Sound Clips of most of my guitars

Hi Wendy,
If you have an oil stone (sharpening stone, 5 -7 inches long) that is moderately coarse, you could use that. Be sure to gauge your progress by using a straight edge across the first and twelveth fret. As Jim and Waddy mentioned you don't need a whole lot.

The method Mike Imbler mentioned that David Schramm uses sounds interesting, and something I'll have to try sometime.

I used to use an oil stone to trace over the frets, but I switched to 400 grit wet/dry (using it dry) on a flexible bit of wood, like thin lathe.