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  #1  
Old 05-01-2012, 10:40 AM
dreadsftw! dreadsftw! is offline
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Default thicknessing backs?

how thick should a guitar back be for a strumming guitar? what do i do to get the wood to the right thickness?
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Old 05-01-2012, 10:54 AM
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It depends on your building preference. Do you want a back that is responsive or one that remains stiff? Responsive backs are made to move (thinner) and stiff backs are thicker. No one should give you a number without knowing that, the wood type, some sense of how stiff your particular set is, how you intend to brace it, and the size of the guitar you are making. It could be anywhere between .090" and .130".
I typically reduce thickness until the back will flex in my hands the way I want it to. I build a responsive back.
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Old 05-01-2012, 11:06 AM
arie arie is offline
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i'm into active backs meant to be played open. as such i'm in the .090 to .095 thick range depending on the species of wood along with radial or x bracing. right now i'm working on a small travel guitar and a 000-12 and i find this to work for me. opinions will vary of course -as they always do.

to thickness the back i use a plane, then an orbital, then a scraper. i check with a dial indicator mounted to the work table.

as stated in the responses to your other posts there really is no one silver bullet to guitar building just acceptable guidelines.

do you have any building books or plans?
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Old 05-01-2012, 05:48 PM
Ned Milburn Ned Milburn is offline
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Some people believe that back and sides should be thick and stiff to create a solid base from which the top will vibrate. It seems, however, that more people believe the back should be resonant and vibrate in sympathy with the top. The guitars that I have built have thin backs (classical guitars - from about 2.4 at thickest to as little as 2.1 or 2.0 mm at the thinnest) and there is definitely a loss of volume when the back is dampened and then played, so I must believe from empirical evidence that the thin and resonant back is the right direction to aim.
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  #5  
Old 05-02-2012, 05:25 AM
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Kitchen Guitars Kitchen Guitars is offline
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Quote:
Originally Posted by arie View Post
to thickness the back i use a plane, then an orbital, then a scraper. i check with a dial indicator mounted to the work table.
Oh! Go ahead Arie! Make me feel lazy! The sandpaper clip on my Jet 10/20 broke in mid thicknessing of a very old hunk of Indian Rosewood. Until my replacement clip shows up I am considered out of biz!
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Old 05-02-2012, 07:09 AM
dekutree64 dekutree64 is offline
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I'm also a fan of thin, lively backs. Usually in the 2-2.5mm range, depending on wood, guitar size, and bracing. Flex and tap to taste, although usually the tap tone is pretty much gone by the time I'm done. Comes right back once the braces are on.

And I do my thinning with hand plane+scraper, but only because I don't have room for a thickness sander and dust vac (and would probably be too cheap to buy them anyway). It's tough work, especially if you can't sharpen worth a darn
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Old 05-02-2012, 11:35 AM
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Howard Klepper Howard Klepper is offline
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You're not going to learn how to build a guitar by tossing out questions about each part of it on this forum as they occur to you. You need step-by-step instructions.

Get a book or two and work from them. Cumpiano and Natelson is a bit dated, but still about the best for a beginner, especially one who does not have a lot of power tools.
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Old 05-02-2012, 02:01 PM
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Kitchen Guitars Kitchen Guitars is offline
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I think asking questions as they come to you is a great way to learn. Helps make those crazy books make sense as you try to go in order and not fall off the path.
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Old 05-17-2012, 11:23 PM
Rick Rule Rick Rule is offline
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Quote:
Originally Posted by Kitchen Guitars View Post
I think asking questions as they come to you is a great way to learn.
Couldn't agree more! Member interaction is one of the strong points of this forum!
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Last edited by Rick Rule; 05-17-2012 at 11:24 PM. Reason: Word choice
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  #10  
Old 05-18-2012, 06:48 AM
charles Tauber charles Tauber is offline
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Quote:
Originally Posted by Howard Klepper View Post
You're not going to learn how to build a guitar by tossing out questions about each part of it on this forum as they occur to you.
Exactly.


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  #11  
Old 05-23-2012, 09:49 AM
pfox14 pfox14 is offline
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It all depends on the wood I am using. I generally thickness mahogany at 2.5-2.7mm, but will go a bit thinner for maple or anything harder like that.
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  #12  
Old 05-23-2012, 03:00 PM
redir redir is offline
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I use a drum sander to get it real close and finish off with a scraper. For years I did all this work by hand till i finally got a drum sander. I could kick myself for all the time I wasted planing boards

Problem is they are not cheap but are a great investment if you want to build several guitars a year.
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