Acoustic Steel String Guitar Setup Note

Guitar setup is a very personal thing. You may do many experiments and tweaks in order to get the most comfortable setup. But doing once is not enough, because it may change from time to time.

External factors like temperature and humidity affect guitar. Most people aim to keep the humidity between 40% and 60%. Before any setup, the guitar should be reasonably humidified, meaning that when putting a ruler on top of its body, its center should bulge slightly, leaving around 1/16˝ on each side.

Here are the steps for the actual setup.

1. Neck Relief

Put a capo on the first fret, and then press on the sixth string (low E) on the fret that meets the guitar body (usually fourteenth fret). The string is entirely straight. It can be a reference point on how much relief the neck has. Measure the gap between the string and the sixth fret. The rule of thumb is the gap should be around 0.010˝. You can get away with a gap slightly lower than that.

Usually only measuring the sixth string and the first string should be enough. A difference across the strings within 10%-20% is tolerable. If the difference is too large, it means the fingerboard is warped.

The way to adjust the neck relief is by tweaking the truss rod. Different guitars have different mechanisms. Usually you use an Allen wrench to adjust a screw in the headboard or the sound hole.

2. Bridge Saddle Height

There are two schools when it comes to measuring the saddle height, the twelfth-fret school and the thirteenth-fret school. The twelfth-fret school just measures the gap between the strings and the twelfth-fret. The thirteenth-fret school puts a cap on the first fret and then measures the gap between the strings and the thirteenth-fret. If nut slot depths need to be adjusted, then measure at the twelfth fret might not be reliable, because it may change as you file down the slots. Personally I like use to the thirteenth-fret. Here’s some numbers for reference. They may change depending on your style.

I just use a 240-grit sandpaper to sand down the saddle. Make sure the pressure on the saddle bottom is even. In the end, when placed on the table, the saddle should stand straight. It should not lean forward or backward. If you need to buy a new saddle, check the radius and size on the guitar’s spec, usually available on manufacture’s official website.

3. Nut Slot Depths

Before you start, it is VERY IMPORTANT to protect the headboard by putting on some protection like painter’s tape. Anytime a mental tool is near the guitar, you have a chance to damage it. I made a serious mistaking not putting any protection and ended up with a few scratches. To cut into the nut slots, you should use files. A cheap way is to use feeler gauges. Cut a few dents on the edge and use it as files. Again, be careful not to damage the guitar. Also be VERY CAREFUL not to cut the slots too deep. Sometimes the first slots goes really slow as you file, but the second slot may go really fast. File slowly and check frequently. The first fret action may look like this.

Once these 3 steps are followed sequentially, it should greatly improve the playability of the guitar.