Without a doubt, the most common job in our repair shop is setting up guitars, referred to as a “set up.” These instruments are brought in for repair because they don’t play well.
What surprises some folks is that all new guitars need a thorough set-up as well. Even when an instrument is perfectly set up at the factory, between the normal settling that new guitars do and the travails of shipping, instruments frequently need a good going-over. Considering that a guitar has over 100 pounds of tension on it from the strings, it’s not surprising that they move a bit and need readjustment. When we sell an instrument, we’ve set the instrument up when it arrives, make adjustments just as it leaves here, and for customers in the area, invite folks back so that we can check to see if the instrument needs a bit more tweaking.
Here’s the procedure we follow for guitars. The same holds true for other fretted instruments. In addition to adjusting the truss rod, nut, saddle and frets (as documented below), the intonation is checked and adjusted as well. This enables the instrument to play in tune as well as possible. Electric guitars often have individually adjustable saddles, which allows for more precise intonation adjustments.
The First Step
Unpacking
The set-up process begins even as the guitar is unpacked. The case and the instrument itself are checked for any signs of shipping distress. (A young Traveler assists with the packing material.)
Neck Relief and the Truss Rod
Tuning
Once the guitar is on the bench it is tuned to pitch and the neck relief is checked.
Checking Neck Relief
Relief is the tiny amount of forward curve required in the neck to allow proper playability and action. Too little relief and the strings will buzz in the lower positions; too much and they will buzz in the middle and higher positions and the action will be poor.
Adjusting the Truss Rod
Relief is controlled by means of the adjustable truss rod found in almost all modern steel string guitar necks. Most classical guitars and many older steel guitars do not have adjustable necks. In these instruments relief is controlled by the inherent stiffness of the neck. While these necks can be adjusted, it is a more difficult process. The adjustable neck makes it possible to control relief with ease and accuracy. This is the sole function of the truss rod.
Action at the Nut
Checking the Nut
Next, the string height at the nut is checked and adjusted. If the nut is too low the open strings will buzz, too high and the guitar will be hard to play in the first position even with low action.
Adjusting the Nut
The slot for each string is individually adjusted.
String Height
Measuring the Action
Once truss rod and nut adjustments are done the action can be measured accurately. It is measured from the top of the 12th fret to the bottom of the strings. Correct adjustment here allows the guitar to play easily and cleanly.
The Saddle
Marking the Saddle for Adjustment
The action is adjusted by raising or lowering the saddle. If the saddle is high it can be carefully sanded to the proper height. If it is too low, the saddle may need to be replaced.
Adjusting the Saddle
Adam is using a stand-mounted belt sander (which can be rough on the fingertips if you’re not careful).
Fretwork
Replacing the Saddle and Strings
After the saddle has been adjusted and the guitar restrung and tuned, the guitar is played and checked in all positions.
Testing
Any tiny unevenness in the frets will show up as a slight buzz or dull note.
Leveling the Frets
To correct unevenness, the frets are first leveled using a long flat file. (Note the aluminum guards to protect the top.)
Recrowning the Frets
After all the frets have been leveled, they’re returned to their proper shape (recrowned) using a specially modified triangle file.
The Final Details
Final Cleaning
Once fretwork is done, the instrument is restrung, tuned and tested again. A final cleaning and it’s ready to go.
Ready to Play!
