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Hello all. Once again, I come to you for advice, as it appears that a number of factors, mostly caused by builder misjudgement and/or error, now have me wondering if I should remove and replace the bridge I just glued to the body.

To explain: First of all, the bridge height wound up a bit thinner than the 3/8" I was shooting for -- right at 5/16".

Secondly, I chose to cut a 10 degree back angle into the saddle slot, which effectively moved the center of the top of the saddle back significantly behind the center of the slot.

Lastly, based on a 12th fret string clearance of 1/16", with a straightedge resting on the first fret, my saddle height is slightly above the 1/2" target. This combined with the thin saddle, results in as much saddle above the bridge as below. Instead of 1/8" exposed, it's more like 1/4".

The biggest problem resulting from all this is that in gluing the bridge down, I didn't compensate for the high saddle exposure/back angle offset enough, and the appropriate string length falls ahead of the front edge of the saddle, so it appears that my intonation will be off considerably.

As far as I can tell, my choices are either a) pull the bridge off and make a thicker one without so much back angle, or b) keep the thin bridge, change the saddle slot back angle, thereby widening the slot, and replace the saddle with a 1/4" one.

Any suggestions or insight into this problem are, of course, greatly appreciated. Thank you all in advance for your help.

Ken

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Mountain Song Guitars www.mountainsongguitars.com

Ken I am not sure what you said regarding your neck angle - with a straight edge flat on frets 1 through 12, or 14 if it is 14 frets to the body, where does the straight edge come into the leading edge of the bridge at?  This is without string tension of course.

Secondly are you saying that you put back angle in your saddle slot or that your bridge top has back angle in it?

Not sure where to go until I hear more from you regarding the above questions.  But for now I can tell you that it's not difficult to slot the bridge on the guitar.  This includes widening the slot or cutting a slot in the bridge on a new guitar that the bridge has not been slotted yet.  LMI and Stew-Mac sell jigs for this, I have one of these jigs from Stew-Mac.

As much saddle exposed above the bridge as what is embedded in the bridge is to much, to tall, a saddle.  This is why I am interested in your neck angle.  I like to have 2/3 of the tree under the ground so-to-speak and 1/3 above.

A 5/16th" bridge height is fine.

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Ann Arbor Guitars

Hesh --

Here are a couple of images that might clarify things:

In both images, the straightedge is lying along the neck centerline, and is 1/8" clear of the bridge. The back angle I mentioned is in the saddle, which seemed like a good idea at the time, in order to resist the saddle's tendency to roll forward over time.

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Mountain Song Guitars www.mountainsongguitars.com

Ken-
re: saddle height
Depending on the bracing/top thickness/string gauge the top will 'rise' up a bit (ie belly) once the guitar is strung up. I usually string up and play the guitar for a week or so before I 'adjust' the saddle height and action. So you may find that the height issue is not as severe as you think, once the guitar has settled in a bit.

I also would wait a bit before deciding on how to correct the intonation problem, though Hesh's advice is excellent.

Cheers

John

Thanks Ken for measuring the neck angle and taking photos of it for us.

I am hoping that others will weigh-in here because I don't want to give you bad advice.

To me what you should do to fix this depends entirely on your own personal guitar building goals.  If this is your first of potentially many guitars I would do one thing.  If this is possibly one of the only guitar that you will ever build I would do another.

I think that there are two things wrong here.  First the neck angle is to great, as evidenced by the straight edge 1/8" over a bridge that is not really to high (5/16").  The second thing that is not right is the location of the saddle and the inability to properly intonate the guitar.

If you re-route a wider saddle slot in the proper location and without any back lean you will still have half the saddle above the bridge and this can cause the bridge to split as the saddle gets pulled forward.

If you route off the bridge, replace it with a taller one, your string height will remain to high, again to much forward pull on the saddle, and if the saddle does not split the bridge the bridge may lift in the back.

So in a perfect world I would re-set the neck to the proper, lower angle first.  Then if I could re-route the bridge slot in the proper location I would.  If not I would replace the bridge.

The neck re-set may seem daunting and I didn't want to take one on either on my first guitar that could have benefited from one.  So I waited until I had more experience.

So if this is your one-an-only and you want it to be perfect I think that it starts with correcting the neck angle.  If you are going to keep building, and I hope that you will, I would get started on the next guitar and try the saddle re-slot for now until you feel up to a neck reset.  And of course what the others have said that things may change favorably over time with the guitar may happen too.

Don't feel bad though I doubt that very many of us at all get the neck angle right on the first guitar - I didn't either.

Also this idea of having a saddle leaning back at an angle although a very good idea and a great way IMHO to belay the effects of torque on a saddle and bridge is not a beginning technique.  In your case it is likely what caused the bridge to not be located properly since it is the saddle top edge that needed to be located properly and you had no way to know in advance where that would be.  The leaning saddle was in a way a moving target for you.

Let's see what more experienced people say and maybe they will be OK with the neck angle and I am being to alarmist here.

In any event it ALL can be fixed so breath easy about that.

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Ann Arbor Guitars

Once again, you guys have given me the feedback and reassurance I desperately needed. I can't thank you enough. I'm now hopeful that I can still salvage the existing bridge.

I'd forgotten that the top will belly a bit with time under string tension, so hopefully the combination of that along with some slight neck relief as a result of string tension will allow me to shorten the saddle to a point that the crown is moved forward enough to properly compensate it.

Quick question: How much of a gap do you guys like to have at say the twelfth or fourteenth fret on the first and sixth strings? Kinkade recommends 1/16" for the first string at the twelfth, but that seems a little high to me.

If after a couple of weeks I'm not satisfied with the intonation issue, I'll rerout the slot wider and straighter, which should correct the problem. I may try to deepen it as well. What's the minimum thickness of material I could leave beneath the saddle? For that matter, not that I'm going to, but could one rout all the way through the bridge and into the top? Instinct tells me that's a really bad idea.

Oh, and Hesh, this is definitely not the last one I'm going to build, but the first of many. Well, the first scratch built one anyway. Regarding resetting the neck, that occurred to me as well, though if I were to make a new, thicker bridge, say 3/8", the straightedge would then come in a hair under 1/16" above the bridge. Isn't this within tolerances?

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Mountain Song Guitars www.mountainsongguitars.com

Neck resets are a walk in a park with me, regarding my first guitar........

Neck resets are not a big deal - unless you're trying to drop the angle. This means either shimming at the end of the heel, or carving away toward the fret board, effectively moving the fingerboard further toward the bridge. Not a good thing.

3/8" is a pretty big bridge, though not terribly out of the norm. 1/4" saddle height is pretty high though, and would put the saddle in the range of .050" further back from the slot.

If it were my guitar, I would pull the bridge and bump it up the the .350"-.360" range. I also don't do back angled saddles. I would also probably pull the frets and re-level the board to lower the angle. How much you can change it without it looking obvious depends on how thick the fingerboard is, but leveling it down about .020" at the end can lower the effective neck angle enough to make a difference.

As to the action at the 12th fret, after nut height and relief are taken care of, 4/64" high e and 6/64" low e are a good starting point (please forgive for not simplifying fractions, but using the 64th as a unit make things simple for us poor SAE folk). Gentler finger pickers and chord strummers might be able to drop to just under 4 on the treble and a generous 5 on the bass. Start flat picking and 5 treble / 7 bass is more the norm, though more of that increase can come from truss rod adjustment rather than the saddle..

Of course since you already have everything together, I would string it up with a dummy saddle, cut the nut, and see where things land as it is now. This will give you a more realistic idea of how far you have to go, and what means would be acceptable.

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Eschew obfuscation, espouse elucidation.

Thanks again everyone for the input. I went ahead and cut the nut, roughed the saddle, leaving the crown flat to keep my options open, and strung it up. To my surprise, it didn't implode and sounds significantly better than a broomstick on a washtub! Woooohoooo!!!

Even more surprising, several strings require compensating toward the back of the bridge, which is great since that's where most the saddle is.

It also appears I'll be able to shorten the bridge slightly, though I'll hold off on that for a spell, at least until the creaking stops. Time to go play a little.

Ken

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Mountain Song Guitars www.mountainsongguitars.com

Make a new bridge and slope the top of it back to reduce mass.   Figure out where the witness point will be with the tilt-back saddle and work out the geometry.   It's a hell of a lot easier to redo the bridge than to redo the bridge and do a neck reset which is your other option.   Always to the least that actually gets the job done...   That doesn't mean cut corners, by the way...the "gets the job done" part is supreme. As in medicine, "first, do no harm."