If you have an Epiphone G-1275, or if you order a Jimmy Page double neck Chibson with the tail pieces all the way to the back of the body, you'll know how difficult it is to find a string set long enough to fit the 12-string neck.
On these guitars, the distance from the tail piece on the 12-string neck to the furthest "D" and "G" tuning posts is a staggering 39 inches. Figuring you need at least another 1 1/2 inches to get a wrap around the post, and you will need stings approximately 41 inches in length - longer than just about every set on the market. There are a couple of solutions for this problem.
D'Addario's 12-string electric set is long enough for this guitar, with the exception of the .008 "G" string. This string is cut at 39 inches, so it will reach the post and just barely make it through the hole - not enough to wrap without slipping. Every other string set I've looked at, other than D'Addario, is simply too short on a number of strings.
D'Addario adds extra length to their strings that are above .013, so what these manufacturers do is to use 11 of the 12 strings from the D'Addario set, and then substitute an additional .013 string in place of the .008 "G" string. This will work, but it may not be the only option.
Locking Tuners - Gotoh, in particular, makes a set of locking tuners that won't look out of place on these guitars. The locking mechanism is inside the post, so it will retain the vintage look of the Kluson tuners. As you tune up the guitar, the string is clamped inside the post. This means that you don't need wraps around the post, so the D'Addario strings will then fit.
Custom Strings - There are custom string makers out there, that will make string sets to your specifications up to 46 inches in length. Guadalupe Custom Strings in Los Angeles, for example, will make a set of 12-string electric strings with an extra long "D" and "G" string. These will cost you more than off the shelf string sets. Guadalupe charges $21 for a custom set, plus $12 shipping for up to 6 sets. Fortunately, you won't be changing the strings as often on the 12-string neck as you do on the 6-string that's getting pounded by your solos.
But here's an even better solution!
C.B. Gitty sells individual bulk strings to people making cigar box guitars. They sell a bulk set of 12x .009 steel strings that are only $3.50 plus shipping. Their strings are made in the USA, and are 46 inches in length, more than enough for the 12-string neck. They also make an extra long .026 nickle wound string, but your .026 D'Addario string should fit. You can order a dozen of these individual strings, and then substitute the .009 Gitty string for the too short .008 D'Addario string. In fact, many 12-string sets use a .009 for this string with their light gauge strings, and it will sound a lot more natural than the thicker .013 string. If you only restring your 12-string neck every 6 months, this would give you 6 years worth of strings, and allow you to use the $9 D'Addario set you can easily grab at Guitar Center of most major music stores. It's a much more economical solution than either installing locking tuners, or having custom strings made.
Who would have thought, the mighty Page double neck SG rescued by the humble cigar box guitar :)
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