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I have joined the top and back and now sanded the top to thickness (glue squeeze out and safety planer marks and stuff). Now while joining the top the two pieces were offset by a little so I sanded them out but now the top is about .09" thick at the joint and about .11" thick at the edge. I tapped the top but I don't know what to listen for. Is there any guide on voicing the guitar top? I know the plan calls for .110" thick top (it's for a Jumbo, LMI's PL48 plan) but I am sure every luthier makes it thinner or thicker depending on what tone they're looking for...

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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

Hey there Fret...

I've only got one guitar under my belt....but....I think (my opinion) that if you don't have your braces on...and they have not been carved....your efforts (tapping) wont' bear fruit.

If you have another top...you could just start over. If it's Sitka and you don't have another top you can get one for really low money.

On the other hand...I took my first top down to 87 thou....and used it. I just braced accordingly.

Chris

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There is no difference between the man that thinks he can....and the man that thinks he cannot.

Tai, these are great questions. You'll find a lot of information if you use the search feature. John Mayes' voicing DVD's are excellent guides as well.

You may have gone down too thin for a jumbo. You may have been alright if you were making a small body guitar or if you had a really really stiff top. You may be able to brace accordingly, but you may want to keep the option open of getting a new top and saving this one for a future small body build.

I second the John Mayes DVDs. Good stuff. Especially the tuning one. Its great to be able to see and hear someone do this. It cant be put into text.

I'd get another top.

What to listen for in tap tuning is a different issue.

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Howard Klepper
http://www.klepperguitars.com

When all else fails, clean the shop.

So what you guys are saying is that now this top is too thin to be able to support string tension, even if properly braced? I think the .90 section is only around the center seam maybe I can back it up with another piece of wood underneath if strength is an issue... I heard about people using tops as thin as .85". The rest of the top is .110 if not more...

Don't tell me this is as bad as shaving the neck so thin that the truss rod shows through... I could get another top but im not paying for a 30 dollar top then pay 50 dollars shipping for it...

I mean visually I can't really tell the difference between the edge and the center, I only know how thick it is by measuring it with a dial caliper (and the thin-ness is only evident at the very edge of the plate... it's much thicker at the center, which I can exclude the edge when profiling the plate). I am sure Torres didn't have a dial caliper so he probably did it mostly by feel and tone...

_________________
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

Usually it is the perimeter of the top, especially the lower bout, that tends to be thinner, and the area around the bridge, especially behind the bridge that tends to be thicker.
Not everybody does perimeter sanding, and not for every guitar, in that case it's better that your top be uniform in thickness.
Although Robert Bouchet used to plane the bass side of his tops thinner than the treble side, but that's for a nylon string guitar.
You have to take into account the sanding you'll do before finishing, it could be another .005", perhaps more if you're not careful.
With a very stiff top (and I wouldn't use anything else on a large guitar) I wouldn't go thinner than .115". But that's me, and others may argue.
Bracing accordingly, I suppose with taller and heavier braces, means nothing if the top is too thin to avoid distortion.

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Laurent Brondel
West Paris, Maine - USA
http://www.laurentbrondel.com/

Ok I think I will get a new top just in case... maybe this top I'll reserve it for classical or something. This top got some small knot too. So is the back thickness as critical? the plan calls for .09" and now the current thickness of the back is about .11"-.10". I got it jointed and installed backstrip. I also got a bottle of titebond original along with my order to make the shipping not as bad, so I can use it for certain applications like joining and closing the box...

_________________
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

I could be wrong here, but I don't believe back thickness is as critical as top thickness. You can probably build the back a little thicker or thinner and be just fine. One thing I've noticed is that "too thick" is rarely an issue other than perhaps one of preference. "Too thin", however, becomes a structural concern. This is particular true of the top, where you have all that string tension pulling on it.

Yea, I should never have taken the top piece to the safety planer... worst case scenario (if I don't build a classical) is cut up the old top and use them as fretboard pad (you know the piece of spruce that goes under the upper bout) or repair patch wood or just use them as side reinforcements. I think the top I got from LMI started at .150 and I was trying to get it down to .109 or close to it... sometimes with the safetyplaner it's easy to overdo it.... I ended up ordering a top set from Stewmac, grade AA Engelmann spruce. I don't know how they compare to LMI because the top I got from LMI is AA and it was called "good" grade. I had been wanting to get Engelmann spruce because I like its lighter color... Sitka was looking a little dark.

_________________
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

Tai, I'm sorry it's such a hassle to get good wood to your door. These are growing pains we all go through. I had to discard a beautiful redwood top earlier this year for the same reasons.

By the way I just found a supplier in Taiwan that also caters to the instrument maker crowd. They got Bubinga, Wenge, Ovantagol, Zebrawood, and other african woods (ebony and etc). I am not sure what their prices are but if it seems reasonable enough it will give me an incentive to get a bandsaw that can resaw so I can buy big pieces and resaw it. I wish I knew where to get top wood though other than the usual (Stewmac or LMI) channel...

_________________
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