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I'm finally nearing completion of my first alto guitar, designing and making the bridge now while I wait for the body and neck to come back from Joe White. This instrument has four double courses (eight strings in unison pairs) and a pin bridge. I've never built or repaired an instrument like this before. I thought I had figured out the string spacing until I realized that the bridge pins limit how close together I can space the two strings in each pair at the bridge end. Of course, I will stagger the placement of the pins, but still, the string anchored in the pin further back has to pass by the pin (of its sister string) closer to the saddle.

I plan to sneak the strings slightly under the heads of the pins they have to pass by, so the string pairs can be a little closer together than half the diameter of the pin heads. I will also cut ramps for the strings as they emerge from their pin holes and head for the saddle. (I'm using unslotted, 3 degree taper pins, btw.)

What I'm looking for here are any tips for how best to do this. My concerns are:

1) that I'd like the strings in each pair to be as close together as possible, given the limitation imposed by the pins
2) that the ramp slots I cut for each string provide the best possible angle of approach to the saddle for each string, and
3) that the ramp slots from the further back pins will, it seems, be cut awfully close to the further forward pins, and I don't want those ramp slots to threaten the integrity of the pin holes of the further forward pins (I hope you can follow that)

If anyone who has worked on pin bridges for 12 string guitars or bouzoukis or whatever can help me out with the details on these issues, I'd greatly appreciate it.

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Todd Rose
Ithaca, NY

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

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

Hi Todd, why do you want the strings that close together at the bridge end; customer request? On my only brdge of this type to date I spread the strings out so the strings in within each pair fan slightly out compared to their spacing at the nut. I do the same thing on mandolins with tailpieces and floating bridges; this is how I like it for playability reasons.

I don’t think the string ramps from the ‘back’ strings will compromise the integrity of the ‘front’ pin holes even if you do it like you propose though, not to much wear on this end of the holes. I would be a bit concerned about the 'back' string getting caught under the collar of the 'front' string etc. If you want the strings really close together, I would go with a single pin for each pair and fan the strings out in separate ramps from there. I believe Dave White and possibly Howard Klepper have posted 12-string guitars here that were laid out like that.

I am not sure what the spacing at the bridge of this ‘zouk was, but the stings just clear the bridge pin in front (3 degree ebony pins). As I said, this is my only instrument of this type to date, so take it for what its worth.

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Rian Gitar og Mandolin

Todd,

Consider using only four bridge pins with a pair of strings in each. I got this idea from Rick Turner and Howard Klepper and used it on the guitar cittern I made. Craig Lawrence used this method for a 12 string bridge and posted a tutorial here on the ANZLF.

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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

This is how I feel when I get such helpful responses like these! Thanks, Arnt and Dave!

The two-strings-per-pin idea is brilliant, and one of those "now, why didn't I think of that?" things. Craig's tutorial on the ANZLF (which I didn't know existed and which is a great discovery in and of itself) is very helpful. Thanks again, Dave, for taking the time to get me a link to that.

Arnt, what advantage to playability do you find with a wider spacing at the saddle between strings within a pair? My experience playing double course instruments is quite limited. I mess around on mandolins and 12 string guitars and such whenever I get one in my hands, but that's about it. All the numbers I've found for recommended spacing between strings within a pair (for mandos, bouzoukis, etc) at the saddle are substantially less than would be dictated by the diameter of the pin heads. My pin heads are .300", or 7.62mm. Half that is .150" or 3.81mm. Add a few thousandths for space between the pin and the string and I'm up to about 4mm. Add half my lowest string's diameter to that and it's about 4.5mm between string centers for my lowest pair of strings. That seems wide to me, and it's about 1mm wider than typical recommendations I'm finding. If I go with a spacing of 3.5mm between the centers of the lowest pair of strings, that would still be wider than the spacing I'd give them at the nut (I don't have my figures handy for the spacing I was planning at the nut, which are based, again, on various recommendations I've gotten; they're all closer there than at the saddle). It would seem to me that having the strings within a pair closer than 4.5mm at the saddle would make picking easier, but, again, that's not coming from much playing experience, so I'm very interested to hear more about your experience with wider spacings between strings within each pair.

Thanks again!

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Todd Rose
Ithaca, NY

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

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

There are no rules about string spacing that seems to work for all players. I know some like to have the space between the pairs parallel, some like the outermost strings closer to the edge of the fingerboard, some like the spaces between the strings in each pair close, some more spread out, some more difference at the bridge that at the nut… It really comes down to personal preference. You need to have enough space between the strings in each pair to avoid buzzing, so I find it necessary to have more space between the thicker strings than the thinner. If the strings are too close it can be difficult to accurately hit the right pair (not if you’re Sam Bush, maybe…), too far apart and you have to work harder to get your pick from one to the other. So there is a bunch of trade-offs and compromises even if you take the pin sizes out of the equation.

I’ll measure the guitar bouzouki when I get it in for adjustments next week I think, those numbers were missing in my notes.

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Rian Gitar og Mandolin

Dave how do you keep the string spacing at the bridge pin? I was thinking of using the brass slugs that you get from the ends of steel strings as separators.

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A higher purpose for wood.
Rich Smith
Issaquah, WA

Rich,

The bridge is slotted - two slots per hole - and you use unslotted pins. Have a look at Craig's picture tutorial on the ANZLF I linked too as it's all made clear there.

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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

I thought this was a pretty awesome way to go about it too. This is an Osthoff guitar, I stole the pic from the 13th fret:

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Burton
http://www.legeytinstruments.com
Brookline, MA.

Thanks for your input, Arnt!

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Todd Rose
Ithaca, NY

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

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