How To: Fully-Compensate a 12-String Saddle, Add String Ramps, Etc.

This 20-something-year-old Yamaha 12-string has a problem. The action was about 1/16" too high overall and the saddle will need to be cut really low for it to play with the 1/16" overall height I like for a "strummer 12-string" setup.

Those marks are where the saddle will need to be sanded-down to. That leaves no back-angle for good downpressure on the saddle with the strings. It'll buzz-out like crazy at the saddle. My solution for this is to add string ramps like you'd see on modern Mexican-made Martins (and some other brands) and then setup as normal -- including modding the saddle into a fully-compensated shape.

First I have to find the string paths from the nut to the termination points of the strings at the bridge pin holes. Here I'm finding where the high E goes.

After I mark them all, I know where I need to cut my slots for string-ramping.

I use a cut-off wheel (metal) on my Foredom (Dremel) to make the slots because I've got a fairly steady hand for this and I'm used to it, but there's no reason you can't do it with a file, razor-file, or mini-saw.

The slots are cut! Yip.

Now I've sanded-down the saddle to its proper height. Here you can see I've put it in the saddle slot and marked positions for where the strings run on it and also lines marking where I need to adjust compensation for each string. Those lines show the spot where the string's front needs to break on the saddle -- meaning where distance from the nut is terminated at.

The general rule of thumb for a 6-string steel-string guitar is that bridges essentially compensate on a straight line that's angled to allow 1/8" farther distance for the low strings. The B-string needs to be notched-back a little of 1/16" to the rear compared to the rest, though, to account for the differences in plain/wound string types. Because 12-strings have a mix of wound and unwound strings that compensate at different places to stay in tune up the neck, you have to notch them differently for each string on the courses with octave strings.

I was asked on Instagram why some pairs compensate the same while others don't. The easy ones are the high Es and Bs which, because they're the same pitch and string type, compensate in the same place. The confusing one is the A course which roughly compensates the same for each string but that's because the wound (lower-pitched) A compensates more to the rear of the saddle (as per a normal 6-string) while the unwound (higher-pitched) A compensates almost the same because it's comparable to a B string tuned down a step which also compensates farther aft.

Here's the compensation notched-in. Not that both the back and front faces are at angles so the strings "break" on a small point.


Rob Gardner said…
What about all those autographs?