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Classical guitar - Flame maple
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Author:  rmcctr [ Mon Dec 08, 2014 1:44 am ]
Post subject:  Classical guitar - Flame maple

Hey guys,

just finished my latest build and wanted to share with you...
All went well except from a little issue with the neck angle that forced me to put a pretty heigh saddle... [headinwall]
Hope won't crack my top...

Top : European spruce
B & S: Flame maple
Neck: Brazilian cedar
Fretboard: Special ebony

Author:  Haans [ Mon Dec 08, 2014 7:21 am ]
Post subject:  Re: Classical guitar - Flame maple

Nice job, but I think the bridge will crack.
How is the neck attached?
I'd try and fix that somehow right away.

Author:  Colin S [ Mon Dec 08, 2014 9:50 am ]
Post subject:  Re: Classical guitar - Flame maple

OK, this looks like a disaster waiting to happen, if the strings are more than about 14mm from the top maximum, ideally 12.5mm then the strings will cause the bridge to rotate forward, which as you can see from your picture is already starting to happen, and the likely outcome is the front of the bridge cracking off. If it is a standard Spanish heel then the way to correct neck angle is to remove and re glue the back with the neck held at the right angle (2mm forward angle from 12 fret to nut). As you seem to have an exceptionally thick finger board, then an easier way may be removing the frets and planing in the correct angle to give a 12.5mm string height would also be possible. The finger board on most 19th century instruments was used to get the correct angle so you often find a board that is say 7mm at the nut tapering down to 5mm at the 12th fret. Ideally you want the bridge to be 9mm and the saddle to protrude by 3.5mm only. If you can remove the finger board then I'd probably do that and start with a thinner board.

It would be a shame to do such good work on the rest of the guitar and then have it fail because of this.

Colin

Author:  mflazar [ Mon Dec 08, 2014 10:26 am ]
Post subject:  Re: Classical guitar - Flame maple

Colin is right. In addition to potential structural damage the high saddle will have a negative effect on the sound. I would try his suggestion to taper the fret board or remove it and replace it with a tapered one. A 2mm taper from the nut to fret 12 will reduce the saddle height by 4mm. I can't tell from the photos whether that will be enough, but it will certainly help.

Author:  cphanna [ Mon Dec 08, 2014 10:57 am ]
Post subject:  Re: Classical guitar - Flame maple

I also agree with Colin. Even before reading his suggestion, that was my first thought as I scrolled through your pictures. Actually, I was going to recommend replacing the fingerboard. But, with patience and caution, you can probably plane or sand a long, continuous "ramp" into the existing fingerboard, then deepen the fret slots as needed, and replace the frets.

My first guitar was a classical and the bridge cracked after a couple of years--not because of an excessively high saddle, but because it was a brittle piece of ebony and because I didn't leave enough material on the neck side of the bridge foot to support the forward pressure on the saddle.

The fit and finish on your guitar looks excellent, by the way. You have every right to be very proud of it. I encourage you to fix that problem before your pretty guitar damages itself.

Author:  rmcctr [ Mon Dec 08, 2014 3:20 pm ]
Post subject:  Re: Classical guitar - Flame maple

Thanks everyone for your replies.

My fretboard is 7mm thick and the total height of the saddle is 16,5mm at the bass side and 15mm at the trembles.Now that you have the numbers what do you think is the best solution?Also the guitar was made with the traditional spanish heel.

Thanks again guys [:Y:]

Author:  Haans [ Mon Dec 08, 2014 3:48 pm ]
Post subject:  Re: Classical guitar - Flame maple

With a traditional classical neck joint, you have a problem. About the best you could hope for is to grind the fingerboard down in a taper, thickest at the nut and tapering toward the sound hole. Then cut new fret slots and refret.
The other alternative is to saw off the neck and reset it, using a bolts to re-anchor it. That would probably entail removing the fretboard.
Neither is a pretty option.

Author:  DennisK [ Mon Dec 08, 2014 6:16 pm ]
Post subject:  Re: Classical guitar - Flame maple

7mm of fingerboard should be plenty to get the change you need, by tapering it as Haans described. Definitely would be my choice.

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