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I've got my top fitted and ready to attach and I got to thinking about the top flexure. The top does flex if I put relatively light pressure on it...and it flexes abit more with moderate amount of pressure.

Since this is my 1st build I don't know how much flexure is acceptable...I carved the braces to the Martin drawings that I have...my top is on the thinner side being about 0.105-0.110"...this is for a steel string dreadnought...so maybe I'm too thin???

I know that this is a touchie feely kind of question that is probably hard to answer via this forum...(text base that is)...BUT...I'll take any help I can get.

Also...has anyone had a Top Failure on their 1st build or even at all??? IF so why??? For now I'm going to hold off on my top attachment until I figure this thing out...

Thanks again for the help,
JP

Remember that the sides will add some stiffness to the top, too.

[QUOTE=Dread1916] I've got my top fitted and ready to attach and I got to thinking about the top flexure. The top does flex if I put relatively light pressure on it...and it flexes abit more with moderate amount of pressure.

Since this is my 1st build I don't know how much flexure is acceptable...I carved the braces to the Martin drawings that I have...my top is on the thinner side being about 0.105-0.110"...this is for a steel string dreadnought...so maybe I'm too thin???

I know that this is a touchie feely kind of question that is probably hard to answer via this forum...(text base that is)...BUT...I'll take any help I can get.

Also...has anyone had a Top Failure on their 1st build or even at all??? IF so why??? For now I'm going to hold off on my top attachment until I figure this thing out...

Thanks again for the help,
JP[/QUOTE]

You can build tops REALLY REALLY thin and they will hold up ok. Just use light guage strings. You may see some problems from the bridge bellying a little, but even that can be fixed with a bigger bridge plate.

try it and see how it works out

_________________
Brock Poling
Columbus, Ohio
http://www.polingguitars.com

I guess I will be taking a would be leap of faith on this one...BUT...to quote Hesh---Believe...

I Believe...I Believe...etc...

This is what I'll be saying when the strings start to go on.

Sorry if I come across as a nervious nilly...but...now that I am looking at this project as it slowly becomes a guitar...I am approaching things with more caution than the abandoment I had when I started bending sides...

I will probably be saying this same phrase while routering the binding and purfling channels too...more to come....

Thanks again for your confidence...
JP

Ah yes... the dreaded WAS, followed closely by TAS (Tool acquisition syndrom).

I went really thin on my first. I thicknessed to .105 to begin with, and with final sanding I'm probably around .90 or even less in some spots. You can actually see the end-block! Medium gauged strings to boot.   We'll see if it holds up for long. Probably won't, but it was a blast anyhow. Then again, it might surprise me...

   So who knows, I might have a first hand account of a fantastic top implosion for you soon...

_________________
I'd like to be able to prove, just for once, that money wouldn't make me happy...

just to clear up..I don't always end up with tops that are .120-.125. It
always varies on the piece of wood in my hands. I've gone under .100
and over .140 before, but it always depends on the stiffness and weight
of the wood.....

_________________
John Mayes
http://www.mayesluthier.com

Good post Heshtone

I don't think I've ever ended up with a spruce top of more than .110 and have gone down to .100 on a steel string. I always use light strings and have never had to look at resetting a neck due to the top bellying. In general I believe that most guitar tops are too thick and could do with a bit of thinning, but of course it all depends on the individual piece of wood and bracing.

On my lutes, the top is .080 at it's thickest point and tapers down towards the shell edge often to .070.

So, glue it on and start with light gauge strings and see how the action develops in time.

Colin

_________________
I don't believe in anything, I simply make use of a set of reasonable working hypotheses.

I'll second PaulB for the great post Hesh!

JP, Hesh is right all the way, and if i may add, don't let any fears stop you or slow you down, it's your first, enjoy, MAKE MISTAKES AND LEARN,there i said it!

Don't want to make any mistakes? Maybe when you see guys at the 100th or 500th still making bonehead moves once in a while will change your concept or perception of what mistakes are!

Just have fun and build like a mad man!

Serge

Been as thin as .090 and thick as .135. Thin it as needed for stiffness and bracing your doing. Should be ok. Coco SJ building now is I think .110 and under that toward the edges, maybe to .085

My first was .108 rough, 28 foot dome, bracing was 8x16mm X, tapered ala Larrivee article in GAL 26 I think. I use mediums all the time, and the top has not moved in five years. All depends on the strength and flex of the topwood. Being my first, I have no idea how it compares to what I do today, but I will bet it was not the stiffest top I have ever used, and I never go below .105 for fear of braces telegraphing thru these days.

_________________
Tony Karol
www.karol-guitars.com
"let my passion .. fulfill yours"

Not sure how wide your dread is, but mine was on a 16 inch wide larrivee style body. Narrower means you can go thinner as well and maintain stiffness.

_________________
Tony Karol
www.karol-guitars.com
"let my passion .. fulfill yours"

First off I must say that Hesh you are the man...Serge too...along with everyone here at OLF...Very kind words and informative too...

I unfortunately live in Florida so Humidity is always going to be a problem...but...I do pay close attention to the operations I am performing and the weather. Since I am shun'd to the garage for my building (my wife would kill me if I built in the house...especially the bathroom...man that is a man's man right there)

My box closure session is post pone due to weather for a few days...but...I should be made in the shade following that. Additionally, I store my parts inside and solely perform operations (sanding, sawing, gluing, etc.) out in a closed off garage. This helps keep the exposure limited and doesn't allow for the wood to change much...BUT...it does make it a longer build time. I'm hoping to get this project completed by summer's end and start purchasing wood for #2 so I can build that in the winter (when humidity is low here)...

Thanks so much for you help and words of encouragement...I won't stop building (weather permitting) and yes it seems like rocket science...but...that shouldn't matter 'cause that's my day job here in sunny florida...

Take Care...
JP

Right attitude JP!