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I have always set my neck angle so the straight edge ends up just level with the bridge, sometimes just below the bridge. Maybe 1/16".   After 6 months to a year, I end up shaving the saddle to bring the action to what I like (which is a little on the low side). On one of my builds this ended up with a very low saddle which doesnt give me the break angle I strive for. So on my future builds I am thinking I need to be about 1/8" below the bridge with the straight edge so a year later when its time to lower the saddle it should be just about right - does this make sense or am I missing something ??

Rich-
What you say makes sense to me, but I think you've got the correction 'going in the wrong direction'.
If the top is going to rise over time, I think you want to aim your straightedge higher, not lower when doing your initial neck set. Then the top can rise to meet your 'aim point'.

If you put your 'aimpoint' 1/8" higher, you will be 1/16" or so above the bridge- as Hesh suggests.
Your saddle will be 'tall' looking when you first string up, but can be cut down later.

If it's a neck curvature problem that's changing the action, I'd suggest using trussrod adjustment to put things right.

Cheers
John

So far I have only had one guitar that I needed to adjust because the top "bellied" and made the bridge rise. This was an acceptable level and I got by with just shaving the saddle about an eighth of an inch to correct it. Since then, I have tried to take steps to keep the top from getting the fat belly... a little heavier bracing and slightly thicker tops.

I am having good success so far with tops around .110 to 120 and the thinner but taller braces seem to be working well for me too.

I too have noticed that the volume is better when the saddle is about 3/16 or so above the top of the bridge. I hadnt really thought of the height of the string off of the top, but a quick measurement reveals that the 1/2 inch sweet spot is just about right. I have also noticed that the sustain is much better with a slightly taller saddle also.

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Reguards,

Ken H

Rich,

I may be in the minority thought camp here, but if the top around the bridge area doesn't dome (aka "belly") up over the first few weeks/months of it's life then it won't be living up to it's full sound potential. I allow for this in the build/neck set - with adjustable necks the saddle stays the same height and an adjustment to the neck is made, with fixed necks I put a hardwood shim under the saddle and remove this at the first "service" of the guitar when it has settled.

All the pictures I have seen of the "killer" pre war Martins etc seem to have pretty big domes in the bridge area even though they started life as flat-tops.

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Dave White
De Faoite Stringed Instruments
". . . the one thing a machine just can't do is give you character and personalities and sometimes that comes with flaws, but it always comes with humanity" Monty Don talking about hand weaving, "Mastercrafts", Weaving, BBC March 2010

hesh, i think you meant bridge rather than saddle in the first line of your post, no?

i don't think anyone has been usefully clear about what they are talking about in this thread, neither the asker of the initial question nor those attempting to answer. when talking about this topic one needs to be clear about whether you are talking about a bare fret board or a fretted board. the measurement can be taken with one or the other so long as you use the appropriate aiming reference, but depending upon your construction technique and sequence often only one way will do, e.g., when one uses a dovetail m&t as opposed to a bolt on, or when one frets before the board is glued on or after the guitar is assembled. unless these things are explicit, the measurement is indefinite and can be confusing.

[QUOTE=crazymanmichael]
i don't think anyone has been usefully clear about what they are talking about in this thread, neither the asker of the initial question nor those attempting to answer. when talking about this topic one needs to be clear about whether you are talking about a bare fret board or a fretted board. ......unless these things are explicit, the measurement is indefinite and can be confusing.[/QUOTE]

Michael-
I think you are being a bit 'severe' here...
The initial question did not ask for a specific measurement; only advice on whether a certain correction in a given direction would be a good idea.
Hesh was clear in referencing his remarks to a fretted board.
The thread really concerns the question of doming of tops- (good or bad?) and whether to correct for future doming when doing the initial setup.
However, you are correct in that a request for a 'cookbook' value should be answered with all the details for taking the measurements.
Cheers

John

[QUOTE=Dave White]
I may be in the minority thought camp here, but if the top around the bridge area doesn't dome (aka "belly") up over the first few weeks/months of it's life then it won't be living up to it's full sound potential. [/QUOTE]

I agree with you 100% on this, Dave.
If you do the initial setup to get 'perfect action and saddle height', then you will need to do a neck reset (or -yuk-bridge shave) much sooner that you would want...unless your top is very rigid. (Plywood and big braces, anybody?)

Cheers

John

[QUOTE=ToddStock] I've found that over time, I get less and less action, but if you just swap out old for new, you're right back in there with as much action as you can handle...[/QUOTE]

This has been my exact experience, but it's swapping the old for new that has always given me problems. Perhaps you could elaborate Todd?   

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Well I am might confused now so let me take another crack at it. First, to clarify - I am using a straightedge across the lenght of an unfretted fret board and at the bridge I am usuall about dead even with the top of the bridge (past approach). Months down the road after all was working fine, the action gets higher on me and I end up shaving down the saddle to restore the action to my liking (around .90 - .10 at the 12th fret). In some cases, this has resulted in a lower than desired saddle which does impact the volume.

Based on some of the comments, I think you guys are saying it is normal for the bridge area to belly up a bit which is natural and some say the sign of a good build. If that were to happen, it seems my action would be getting lower not higher.

I was thinking instead that my neck was pulling up which would cause higher string action and as the neck seems to be good an level with the proper relief I thought by setting the neck so the level was slightly under the edge of the bridge would result in super low action, requiring me to shim the saddle for the initial stages of aging, and then as the neck pulled up a bit I would remove the shim or shorten the height of the higher than normal saddle.

Her is a really rough sketch of what I am explaining. This wouldn't be the first time I have had brain block when it comes to seemingly simple concepts of the build process. Wondering if I am doing something more fundamentally wrong in building my necks (too light for exampe) or if I am just not paying enough attention to the neck alignment in the first place.

And no problem with your comments Michael - I like your up front style - hope this makes it clearer.

[QUOTE=rich altieri]
Based on some of the comments, I think you guys are saying it is normal for the bridge area to belly up a bit which is natural and some say the sign of a good build. If that were to happen, it seems my action would be getting lower not higher.
[/QUOTE]
Rich-
I'm definitely not 'on the same page' with your analysis. If the top rises (bellies up) the bridge and saddle will move 'up'- further away from the plane of the fingerboard, and the distance between the stings and fingerboard will increase.

If the fingerboard is still fairly straight a month or so after stringing up, and the action is higher, then I'd focus on changes in bridge position when reaching a diagnosis. If the neck is changing shape, then the fingerboard will reflect the change- either by increased curve or by showing a definite 'change in direction' where the neck meets the body.

Anyway, I think the problem is mostly with language here- your idea of doing a 'pre-correction' is pretty commonly done.

Cheers

John

I love you guys

I can't believe I missed this. Of course as the belly rises so would the strings causing high action at the 12th. I feel like a real dumb s__t right now and should know better. Anyways, I think I got the idea now and also reviwing that post Hesh so thanks to all of you for chiming in and helping me get this through my thick skull.

BTW Hesh - been mostly lurking from hotel rooms these days. On the road alot with day job and getting ready to start my next build which is a small body guitar for travel. Anyway, hope you all had a good 4th - I did and home for a couple weeks so off to the cellar.

Thanks again

Well, I have noticed that the more my belly rises, and the older I get, the lower my action gets.  I don't understand.   

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Waddy

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Sound Clips of most of my guitars

Waddy I am cracking up.   

Ok i did not see anyone say this, or I just missed it. This early in the life of the guitar the most likly canidt for this much change is an under supported fretboard extension which can cause the top at the fretboard extension to belly DOWN which may appear that the bridge area has bellyed up. and cause a high action. and or the neck has excessive relief now which will cause the same thing.

I did not mean to post yet still checking for typos

here is the edit

Ok I did not see anyone say this, or I just missed it. This early in the life of the guitar the most likely thing for this much change is an under supported fretboard extension which can cause the top at the fretboard extension to belly DOWN which may appear that the bridge area has belly up. and cause a high action. and or the neck has excessive relief now which will cause the same thing.

Yes we are! 

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Waddy

Photobucket Build Album Library

Sound Clips of most of my guitars