Measure the following parameters carefully, using an accurate ruler or calipers,
to within .03 inches or .8 mm: length, width, height and "E-to-E" string spacing.
The diagram above illustrates where the measurements should be taken.
For the E-to-E string spacing measurement, measure as closely as possible to the
centre of each string slot.
The E-to-E spacing measurement is the most important parameter to match with a replacement
nut. It determines the string spacing on the neck, and how close the strings are
to the edge of the fingerboard. It is not adjustable; unlike the length, width or
height of a nut, string spacing cannot be adjusted to fit.
Should you find a nut that is a little too long, high or wide, you can easily remove
the excess material by working the part back and forth along a piece of 600-grit
sandpaper placed on a firm, flat surface.
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| STEP 1. Remove the strings. Most acoustic saddles will lift right out with pliers. Occasionally you may find one glued in. If so, get a competent guitar tech to complete the job. Do NOT pry it out as you may take some wood from your bridge with it. Once removed, clean the slot of any debris. | STEP 2. Check if the Graph Tech saddle fits into the slot, without forcing it. If it’s too thick, place a 400 to 600 grit sand paper face up on a flat surface and sand down the sides of the saddle until it fits in the slot snugly but is easily removable. You may have to reduce the length also. | STEP 3. The saddle should slip in easily, but snugly enough that you are able to turn the guitar upside down without the saddle falling out. Next, you need to adjust the string height. |
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| STEP 4. Put your old saddle and the Graph Tech saddle together and match up the tops. With a pencil, mark a line along the bottom of your new saddle. | STEP 5. Lower the saddle down to the line by rubbing the bottom of the nut on the sandpaper until you achieve the proper height. Work in small increments; check your work frequently to ensure you don’t remove too much material. | STEP 6. Measure the gap between the top of the 12th fret and the bottom of the low E string. It should be just under 3mm (.118”, or about a stack of 12 business cards if you don’t have a ruler) and for the high E, 2mm (.079”, or about a stack of 8 business cards). |