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I'm would like to make the space between the strings the same at the bridge.
How do you compensate for string thickness when locating the bridge pin holes?

Considering that the bridge pin holes will not be on a straight line, and is for 2.5" string spacing at the bridge, is the Stew Mac String Spacing Rule something that I should consider buying?

Thanks for your help.

Ron M.

Ron my friend I can answer the question about the Stew-Mac string ruler - the widest setting that I can see on mine is about 2 3/8th". But it is still fantastic for nut spacing.

I am sure a math major will be along shortly to help you with the rest of the question.

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Ann Arbor Guitars

Hi Hesh
I appreciate you telling me the max spacing. A customer service rep at Stew Mac said that it was 2-7/8". Thanks

Ron M.

On issue this process will cause is that to do this the center of a line drawn from out side hole center to out side hole center will not fall on the center line of the guitar therefore the hole pattern will not be centered on your bridge if your bridge design is to be centered on the guitar. This is because the strings are progressively different diameters.

This also means that if you intend the center of the gap between string 3 and 4 to be the center of the fretboard. the taper of the neck and fretboard is different on one side than the other because the distance from the center of the board to the center of E strings will be different. this issue is the reason historically the centers of the strings are used to set the spacing with the distance between centers of the strings being the control measurement if you like I can lay out on cad for you what will happen when you try to do this. I need the gauge of strings and the spacing you want at saddle and at the nut and the scale length. It is easy to figure out but not the best means to arrange a saddle and neck in my opinion.

I take it tht at the nut you plan on using standard spacing (center to center spacing) then at the bridge you wan to use edge of string to edge of string spacing. this will affect the centerline projection of the neck.

I just did a few baritone bridges, and because the strings get sooooo large on the bottom end, I decided to add a touch more space between 3/4, 4/5 and 5/6. Using the bridge pin hole jig I have, which normally uses equally sized spacers to locate the bridge for drilling, I simply added some of the 10 thou black fibre between the spacers (10 thou, then 20, 20).

Now I agree that the holes may now not be placed dead centre on the top of the guitar, but I really dont see this as a huge issue, as we are not talking a huge amount .... I also set the bridge according to where the neck lies, to get the FB edge to string spacing to be where I want it .. if that means the bridge moves a half mm, so be it.

here is the jig .... you can make the spacers whatever you need ... I planed and then micrometer mine, they are within a thou of each other.

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

You are very welcome Ron.

I just rechecked and at least mine only goes a tad over 2 3/8th". Perhaps they changed it since I bought mine or perhaps the customer service rep is rong......

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Ann Arbor Guitars

On second thought is there any reason why one could not skip two positions instead of one?

Anyone know?

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Ann Arbor Guitars

the stewmac string space rule is based off center to center of the strings in other words it takes a given length and divides it into 5 equal segments. using the next adjasent mark will not produce equal saces between sting edges.

Thank You Michael

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Ann Arbor Guitars

the formula would be this

X=the total pin center to pin ceter: if your bridge is 2.5" outside pin center to outside pin center then X is 2.5 or 2.38 or what ever your choice is

X-(the total with of strings 2 through 5 + 1/2 the total width of strings 1 and 6) = Y or The available room for spacing.

Y/5 = the amount of space between string edge to string edge

based on a 2.5" pin spacing and .054-.012 stings here is the calculation

1st .012
2nd .016
3rd .024
4th .032
5th .042
6th .054

X=2.5
X-(the total with of strings 2 through 5 + 1/2 the total width of strings 1 and 6) = Y or The available room for spacing.
2.5-(.114+.033)=Y or 2.5-.147=2.353 available room between strings
2.353/5=.4706 between string edge to string edge.

that is some pretty wide spacing

I think this is wrong. The StewMac rule is intended to compensate continuously for string diameter to give equal spacing between strings. If it gave equal center to center, it would have to be graduated in sets of six marks; but it can be started anywhere, which only makes sense if it is continuously adjusted for diameter (for some typical string set).

I've thought about compensating spacing at the bridge for equal between string spacing, but decided against it, after giving it some thought and talking with good players. Players are used to equal center spacing at the bridge, and I do not think it would be helpful to do equal space between strings; if anything it would throw people off.

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Howard Klepper
http://www.klepperguitars.com

When all else fails, clean the shop.

Absolutely Howard ... the SM marking rule is NOT equally spaced ....

I just checked the rule to see what happens if you use the every third space, instead of every second (this way you could easily go beyond the 2 3/8 its intended for).... it compensates for string gauge even more, maybe you would like it, maybe not. The difference is in the upper three strings (you can compare the two using the smallest end, every third space, vs the same total spacing from the other bigger side)

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

Lmi sells a Bridge Drill Jig .It says in the catalogue that hole spacing is equa-distant,there is no compensation for string gauge.Probably because what Howard said about players probably aren`t used to this.The jig is on Page 136 and in my opinion is pretty pricey.I like the looks of your jig Tony.I can probably muster up something similar at reasonable cost.I did get one whole a bit off on one of my builds and it really bothered me.It wasn`t much,but was noticable.I do think a jig would be best.
James

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James W Bolan
Nashville Tennessee

Here's how Frank Ford makes his nut spacing rule, it should work equally well for a bridge.

http://frets.com/FRETSPages/Luthier/Tools/NutRule/nutrule.html

Ron M, you didn't say why you wanted to this. I've never played I guitar that had the strings spaced like this at the bridge (that I know, anyways), so I can't say whether I would have liked it or not, but what do you hope to achieve?

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Rian Gitar og Mandolin

James .. reasonable cost ???? other than the locking knob and threaded insert, its pretty much cobbled out of scraps ... total cost in Dollars - about 2. well OK, you need a couple clamps too !!!

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

Yeah that`s what I`m talkin` about. I can afford 2 dollars.
James

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James W Bolan
Nashville Tennessee

Just curious...what are everyone's typical string spacing at the bridge? And what dictates your choice?

My spacing is typically 2.125" to 2.250" and is reflective of the neck width at the 12th fret. For a 12 string I'm working on I increased that to 2.375".

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JJ
Napa, CA
http://www.DonohueGuitars.com

Thanks everyone for your responses.
It's for a Weissenborn Style Guitar that I built. I didn't locate the bridge properly or the bridge pin holes, so I'm trying to get it right this time.

The MIMF plans specify the bridge pin holes spacing from the center of the 1st string to the center of the 6th string as 2-1/2".

Ron M.

Hi Michael,
Thanks for your generous offer, but I'll figure it out, eventually. The nut spacing is
1-11/16.

Ron M.

What I usually do on a spec guitar is 1.75" nut, 2.25" 12th fret and bridge.

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Howard Klepper
http://www.klepperguitars.com

When all else fails, clean the shop.

I'm really curious, Howard. How do you do 2.25 at bridge and 12th fret?

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Waddy

Photobucket Build Album Library

Sound Clips of most of my guitars

Waddy, the convention, as I keep hearing it, is to give the width of the board for the nut and 12th fret measurements, and the center to center of the E string pin holes for the bridge measurement.

Or was that not the question?

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Howard Klepper
http://www.klepperguitars.com

When all else fails, clean the shop.

I thought that the width of the fingerboard at the body joint would also be the outside string centers on the bridge.
eg: 2.25" at body joint = 2.25 on bridge.

Peter

This has been my understanding as well. I asked the question to determine if there is, in fact, conventional wisdom on this. Peter uses the body-join fret width as his target string spacing. Any other "rules of thumb"?

Are there occasions where different style players prefer different spacings...i.e Bluegrass flat pickers vs. finger stylist players?

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JJ
Napa, CA
http://www.DonohueGuitars.com