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I'm coming up on the tail end of the construction part of my first build and I'm stumped (again) . I have the body all routed & bound as well as the headstock (after much stalling around). I then trial fitted the neck one more time, & found it to be tilted back ever so slightly after gluing the fretboard on. So, I did the necessary adjustments, & now have the straightedge sitting where it supposed be...on the top of the bridge. I'd like to determine the bridge location so I can begin the finishing process.

What I can't seem to figure out is 'where' to locate the bridge (allignment wise) so it's spot on. Since the neck has not been glued in permanently, the neck can shift ever so slightly and alter the allignment. I'm also not sure where to measure to, for the scale distance, so that the compensation will be OK & so it will intonate properly? It's a 25.4" scale. The saddle is a temporary...
Do I need to tighten up the fit of the neck now, & take up the slack so there's no sideways movement or does that occur when doing the neckset?




Thanks, ~Rich~
RichB38845.7877430556

I take a bit differnt approch. One of the last thing in construction I do is to locate and glue the bridge. I attach the neck and glue down the extension then locate the bridge. That way I know that the bridge is correct for neck and fretboard no mater what. Once I glue the bridge on I then I. But most do as you have done. but also I fit my neck as snug as possible and never work the tenon or mortise just the cheeks as needed for pitch and yhaw.

Rich, lookging great, what Michael said,

I use a Saddlematic tool to set my bridge/saddle and it also has some intonation pins you can use. I also use the Intonator system from StewMac once the bridge is set before I cut my saddle slot. I saw a thread recently where someone had made a tool like the Saddlematic out of some simple hardware supplies, you might want to look it up in the Archives. You can do it just by measuring and use the preslotted saddle on the bridge like most.

Mike
White Oak, Texas

No Hesh, I was planning on finishing the body & neck before gluing the neck (Dovetail) in permanently. I thought it was kosher: to first locate the position of the bridge, then mask off the area where it sits, so no lacquer or material would be there...only the bare wood. Then, I would not have to do the scraping off method after it's been painted, so the glue will stick. Like you. I don't think I'd be up for that. But I'd still like to know how to locate the bridge accurately? The bridge is already slotted. Where do you measure to? The high E, the middle of saddle, or what, so the compensation is correct?RichB38845.911099537

I to have a saddle location tool. There are 2 things to remember about this. What string gage and what action.
    Compenstaion for intonation. I like to base this on the string gage. If you are using lights ad .100 to the scale length for compensation and .125 for mediums. Though this isn;t iron clad it will get you close
    Action height will also play a part in the intonation compensation. So many things to play with the ole head.
    Most I think will have an opinion on this but I did find the .1 to .125 a close set up.
   You can tweak the finall on the saddle. Rememeber the human ear picks up sharp before flats
john hall

John, great points, I watched with awe on the thread a few weeks back on these very subjects. This is something that I am committed to learning more about and attempting to get better and better at it. Thanks to you guys and this forum that opportunity exist.

Thanks

Mike
White Oak, Texas

Thanks...Hesh, Michael & others..I think I've got it now guys (most of it). I read over the Stew-Mac instructions a few times and it's making more sense now. The Saddlematic does look like a good way to go, especially for future use. For $29, it's well worth it. That holds true for intonator tool as well. I had seen these early on, but I thought there might be a way to get around it w/o it getting too complicated...I guess I'm just used to Strats, where all you need is a screwdriver!

RB

She's lookin' great Rich! Nice!

One thing to keep in mind: if your bridge pins holes are already drilled (or string holes in the case of a pinless bridge) before you put the bridge on the guitar, then where you place the bridge in the side-to-side dimension will determine where the strings lie over the fretboard. If your bridge pin holes aren't perfectly placed in relation to the outer corners of the bridge, then you could have the bridge centered by the outer corners and end up with the strings lying over the fretboard not quite how you want them. To me, the lay of the strings over the fretboard (measuring from the outer strings to the edge of the fretboard) is a critical thing, whereas the centering of the outline of the bridge itself on the guitar's top is not critical. So I would place the bridge, side-to-side, according to the location of the holes and not worry if it's a little off otherwise.* Did this make sense?

*One way of doing this is to use lengths of thread stretched taught from the nut slots down to the bridge pin holes. Ask me for more details on this if you're interested.

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Todd Rose
Ithaca, NY

https://www.dreamingrosesecobnb.com/todds-art-music

https://www.facebook.com/ToddRoseGuitars/

P.S. I bought an intonator from Stewmac and then returned it before I ever used it because I learned a simple way of doing what it does (even more accurately, I think, though we're splitting hairs, here) from Al Carruth right here on this forum. You use a little piece of a B string put under each string on top of your saddle, while the saddle top is still flat. Move the piece of string forward and back until the intonation is right for that string, make a mark, and move on to the next string. Do this for all of them, then shape the top of the saddle accordingly. If I haven't explained this clearly, I'll try again, and/or you could search the archives and find Al's instructions.

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Todd Rose
Ithaca, NY

https://www.dreamingrosesecobnb.com/todds-art-music

https://www.facebook.com/ToddRoseGuitars/

I use the saddlematic as well but I have altered it. I have a permanently saddle mounted where the locator pins were so I just insert the saddle in to the slot after doing the nut index portion of the saddlematic setup. I feel that I have better control of the slot edge this way. I just never liked the tapered pins. to hard to control with accuracy.MichaelP38846.5007291667

Todd,
The explaination you gave is found in Jim Williams "A Guitar Makers Manual". That is where I learned this method. However, it doesn't do any good if you did not add compensation to your scale length corretly I have used that method with great accuracy. Take a B string and cut it up in 6 1" lengths. Then each 1" length bend into a small hockey stick shape. Place the small section of the hockey stick under the string on the flat saddle and then tighten the strings up. Play the open string and tune to perfect pitch. Then fret the 12th fret, if sharp, losen the string and move the little "hockey stick" toward the bridge pins, if it is flat, then move it towards the soundhole until it is equal to the pitch when plucked open. Draw a pencil mark exactly in front of where the "hockey" stick is. Do this for all the strings, then remove the strings and saddle and file to the line, making sure you round over the back side of the saddle slightly. Hope this helps to clarify.
Tracy

cheaper way than the intonator is just to use a set of allen keys, then you have all the different sizes at your disposal! just get one of the big sets from walmart or home depot,

paddy

This question, from theory to reality, is on my bench right now, as I attempt to intonate my first saddle.

I used a very wide saddle .25" (6mm), and I rotated the saddle 4°. I went with the "typical" recommendation to glue down the bridge so the middle of the saddle would be at the scale length. Presumably, intonation could be adjusted in either direction then. This went against my logic, but I did it anyway.

My logic told me that their would *never* be intonation compensation for *any* string that would make the string length less than the scale length. So, I wanted to glue the bridge so that the scale length was right at the leading edge of the saddle, not in the middle. That would give me a full .25" of saddle width to work with, and would result in leaving a good width of bone behind the string, when the filing was complete.

Now I have a saddle that will be almost completely filed away on the treble side (at least the high E string.)

So, for future reference, the question to experienced builders that are especially keen on intonation: where should I locate the leading edge (toward the nut) of the saddle?

Thanks!

Dennis

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Dennis Leahy
Duluth, MN, USA
7th Sense Multimedia

I usually put the leading edge of the saddle on the high E end exactly on the 'theoretically correct' position: with no compensation. Since the saddle extends beyond the strings this puts the front of the saddle at the E string position slightly behind the theoretical point, but not usually enough to be correctly intonated. From there I start with a flat-topped saddle and use a length of string to find the correct break points. You do this _last_, after all of the other things, like relief and action height, are set, and use the brand and gauge of strings the customer will be using.

One builder I know tries to get the saddle exacly on the correct spot to have the intonation come out right when the high E string rides off the leading edge. He reasons that no guitar ever got _longer_ with age. This allows you the most useable saddle for correcting the intonation over the years as the neck and body slowly fold up.

So you have a 1/4 inch saddle slot, the bridge is glued down such that the saddles leading edge is right on the scale length, measured where ?? The high E, the D/G split ??? You are pretty much right on in your assessment that no string should be shorter than the scale length, however the program I use (fretcomp) says that the G might need it. I find that with a 1/8 saddle, comped 2.5mm to the slot centre between the D and G (ie add 2.5mm to the scale length, on both 24.9 and 25.4), with a 2.5 mm slant, gives that ability to intonate very accurately. I do find the odd one that sometimes wants a bit more forward on the G, just like the program says. I do plan to go to a 3/16 saddle on all future multiscales and baritones, just to get that ability to pull the 3rd up, and possibly push the low string back more (especially on baris, with the larger gauge)

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

[QUOTE=Alan Carruth] I usually put the leading edge of the saddle on the high E end exactly on the 'theoretically correct' position: with no compensation. ...
[/QUOTE]
That was what I wanted to do, but could find no reference that mentioned it. Actually, having zero experience in performing the intonation, I had thought to put the leading edge of the center of the saddle, (the D-G gap's leading edge), at the scale length.

[QUOTE=Alan Carruth]
One builder I know tries to get the saddle exacly on the correct spot to have the intonation come out right when the high E string rides off the leading edge. He reasons that no guitar ever got _longer_ with age. This allows you the most useable saddle for correcting the intonation over the years as the neck and body slowly fold up. [/QUOTE]
And that thought is the continuation of the thought process. (I had never heard that the G string sometimes needs "negative compensation", if that is the correct way to express it.) I sure do wish I now had 3/16" of room on my 1/4" saddle for intonation, but now I have probably less than 25% of the overall width to work with, considering at least a tiny rounded edge in back.

Well, I can see that I should have posted this question here, before I glued the bridge down.

Next time!

Dennis

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Dennis Leahy
Duluth, MN, USA
7th Sense Multimedia

I like that Allan - no guitar ever got longer with age - how true. BTW, my method and bridge geometry essentially does just that - put the high E right on the leading edge, or very close, about .5mm to it.

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

[QUOTE=Alan Carruth] ... and use the brand and gauge of strings the customer will be using.

[/QUOTE]

John Hall said something similar in his post. I find this a little odd. Many of the guitarists that I know have a box of guitars strings. When they get a new guitar, they spend a few days trying out different sets of gauges and brands of strings to find the one that works best for that guitar. Some guitars like Martin light strings whereas others like D'Addario mediums or John Pearse, etc. Most of the guitars I've seen are braced for at least medium gauge.

Is it your experiance that players settle on a particular brand and gauge and seldom change?

The amount of compensation that a string needs seems to be related to how close it is to it's breaking point, sometimes called the '%T'. Usually the high E string is closest to breaking, and needs the least compensation. Octave Gs on 12s need even less, because they're closer to breaking, and you can get into trouble if you put the saddle too far back with them. B strings need more compensation, since they are generally made of the same material as the E, and thus could be tuned as high without breaking (the string, that is!).

G strings are always a problem. If you make them out of the same material as the E and B they will be really slack. They tend to bend a lot if you don't fret carefully, have intonation problems, and give a kind of 'fuzzy' impression of pitch. If you can make a wound one of the same overall diameter the tension will be about the same, and it will be closer to it's breaking point, since the core, which takes the tension load, is smaller. But you can't make the core too thin without running the %T up too high, so there are restrictions on how thick the wrap can be. If you use a thick wrap and the thin core you could actually be at a higher %T than the E string, and need less compensation.

That's why you have to always set up the intonation for the brand and gauge of string that the buyer will use, if possible. Different manufacturers solve these balance problems in different ways.

[QUOTE=Mike Mahar] [QUOTE=Alan Carruth] ... and use the brand and gauge of strings the customer will be using.

[/QUOTE]

John Hall said something similar in his post. I find this a little odd. Many of the guitarists that I know have a box of guitars strings. When they get a new guitar, they spend a few days trying out different sets of gauges and brands of strings to find the one that works best for that guitar. Some guitars like Martin light strings whereas others like D'Addario mediums or John Pearse, etc. Most of the guitars I've seen are braced for at least medium gauge.

Is it your experiance that players settle on a particular brand and gauge and seldom change?
[/QUOTE]

Hi Mike,

I'm a newbie, and I'm curious if you just cut nut slots for medium gauge strings?

Thanks,

Dennis

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Dennis Leahy
Duluth, MN, USA
7th Sense Multimedia

I like the idea Alan mentions that “no guitar ever got _longer_ with age”.
Another reason for setting up your intonation a bit longer (flat) than short (sharp) is that it is easier for a player to play sharp with technique than it is to play flat. I know it depends on playing style but, for my taste, I position my saddle a tad back to the tail. I think putting the leading edge of the saddle on the high E end exactly on the 'theoretically correct' position, as Alan said, will accomplish this. Along with the usual slant that we set our saddles for the lower strings, this seems to compensate most strings nicely. (To my ear anyway).
Also, if you are carving away at the saddle to “fine tune” the intonation, be sure to play the instrument for a while first, to let the strings “break in” a bit.

Wade

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Wade
Nashua, NH
http://www.wadefx.com

[QUOTE=DennisLeahy]
Hi Mike,

I'm a newbie, and I'm curious if you just cut nut slots for medium gauge strings?

Thanks,

Dennis[/QUOTE]

Well, yes and no. I usually use light gauge strings. When I'm cutting the nut slots, I use the smallest nut slotting file that I own that is not smaller than a light gauge string. I use the sizes printed on an Elixor light gauge package that I have in the shop. As it turns out, these slots are large enough for medium strings. If I had more files, the nut would be slotted for lights and mediums might not fit.