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hi all
well it's been a long haul but I'm starting to "put it together".
I had a couple of major mishaps with this soundboard which is a a lovely bit o' euro, much admired by lecturers and students but I was on the verge of scraping it and starting again but here we are at this stage.
please don't hold back in saying what ya think.
oh and it weighs 5 .75 oz. - 162 gms
yours Geordie

_________________
some tunes on acoustic and guitar synth.
http://www.youtube.com/user/TheGeordieAdams
http://www.myspace.com/geordieadams

Hi Geordie,

I'm by no means an authority - I've completed only one guitar so far, which happened to be a classical guitar as well. I'll let you know my thoughts anyways.

I don't know how thick your top is, but your braces seem prett massive to me. I think you couls shave them down considerable. I used a redwood soundboard (about 2.5mm thick) and my fan braces were definitely not taller and if I remember correctly also not wider than 4mm.
The guitar has had no structural issues so far (9 months old) and has developped a very sweet and balanced tone.

Again - I'm no authority, and maybe your braces are smaller than they appear to me on the image. And maybe you need stronger braces if yout top is quite thin

just my impression from the image...

best, Christian

hi
thanks Christian, thats what I’m after.
the top is 2.2 mm
fans are 4mm wide 6 high
the two transverse are 6 mm wide 15 high
the diagonal is 4 wide 10 high
the outline is Hernandez with a nod to Fleta in the braces bracing.
yours Geordie

_________________
some tunes on acoustic and guitar synth.
http://www.youtube.com/user/TheGeordieAdams
http://www.myspace.com/geordieadams

Hey Geordie

Finding the right balance for a bracing system is something that comes with experience. First tries are often too cautious, which leads to too much bracing (and very likely a very "tight" sound) or too daring (not enough, with structural consequences). This is why the best way for starters is to copy a proven bracing pattern from a plan.

From what you show and describe, it seems fairly strudy and maybe a tad on the heavy side. That is better than too light as you can always sand it down a bit by reaching in the soundhole even after the guitar is completed.

My 2 cents is that you are quite safe with your design and I recommend that you carry on from there...

Good luck,

Pat

Hi Geordie,
As I worte, my redwood top was around 2.5 mm, the fans were 4mm wide and high. I think the transverse braces were around 12mm high (the guitar was based on the Hauser btw.)

Assuming that redwood/cedar tops should always be 10-15% thicker than spruce top, and assuming that this holds true for our two particular tops, your spruce top should be quite comparable to my redwood top (that's quite a stretch, but all I can offer).

I felt my guitar was on the brink of being overbuilt. The g-string was muted a little using nylon strings, but I could compensate for that very nicely by using Savarez carbon strings. With the carbon strings it sounds balanced across the strings.

I made a mental note however that I would use a thinner top and/or thinner braces for my next classical guitar.

So, again assuming that your spruce top is comparable to my redwood top in terms of stiffness, I'd say that your guitar will be somewhat overbuilt as well if you keep the braces the way they are now. If this were my top, and based on my very limited experience, I'd shave down the braces a bit more.

Again, keep in mind that my assessment is based on limited experience of only 1 guitar that I've built so far, a couple of assumptions and on your measurements and two pictures. I may be totally off with what I wrote...

cheers, Christian

Edit: I agree with what Pat wrote...right now your on the safe side and my suggestions could mess things really up

In my opinion, and the stiffness of the top would have a lot to do with it, the braces are bigger than they need to be. If it were me, based on my limited experience, I would taper them more gently from the bridge position rather than having such sudden shape changes. I would also vary the heights down from the center to the outside. Say 6mm in the center, the next ones at 5 or 5.5, then down to 4 or 4.5 then down to 3.5 or 4 mm on the outside fans. Here is what mine looked like, and I know we are talking different designs here, so we're comparing apples to oranges a bit, but.....

This top is about 2.1 to 2.2mm in the center and somewhere in the 1.5 to 1.6mm range around the edges of the lower bout. The braces are, center 4 x 6.5mm, 3.5 x 5.5mm, 3mm x 5mm, and 3 x 4mm. I tried to taper them more in a soft bell shape with a bit of flair at each end, though I tapered more gradually toward the tail than toward the sound hole.

On my first, the top was 2.4 to 2.5 in the center, and more like 1.7 to 1.9 around the perimeter of the lower bout. The braces went from 3mm x 5.5mm center, progressively, down to 4mm high on the outside fans. Both tops were German Spruce bought at the same time. Nice and stiff, but probably AAA tops from Uncle Bob.

These are just examples. Not trying to tell you what you did is wrong, but I believe it'll be a little over braced with the present plan. Is it to be a standard classical, or a flamenco? I notice that there are no closing braces at the tail. Maybe your plan doesn't call for them.

_________________
Waddy

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Sound Clips of most of my guitars

hi
Pat and Waddy
many thanks for your input guys.
Of course graduate them towards the bottom and outwardly, dumb me!.
I’ll do that while I’m having my first go at “voicing” the top - probably be lost on me but my tutor is back on Monday and will guide me through it, I’m exited.
best regards
Geordie

_________________
some tunes on acoustic and guitar synth.
http://www.youtube.com/user/TheGeordieAdams
http://www.myspace.com/geordieadams