Introduction
There is more than one correct way to tie strings on a classical guitar. Here is my own method, along with a few useful tips and important precautions to help avoid any risk of damage.
The first step is always to protect the soundboard behind the bridge. I use an electrostatic protective sheet with a small piece of adhesive tape in one corner to make removal easier — this prevents nail marks and scratches on the varnish.
Protect the soundboard before starting — an electrostatic sheet with a corner of tape for easy removal.
I
Classical 6-hole bridge
Bass strings
Wound strings
Through hole and loop
Pass the string through the hole and form a loop. The most important point is to press the loose end of the string firmly against the back face of the bridge before tightening — this is what keeps the knot from slipping under tension.
Tightening the knot
Hold the loose end in place and tighten the knot. A single loop is sufficient for the wound bass strings — a second loop can be added for extra security if preferred.
Treble strings
Nylon & carbon
Ball end and loop count
For treble strings, after passing the string through the hole, use a lighter to create a small ball at the end — away from the instrument. Then make a loop as with the bass strings, adding one or more loops depending on the string's thickness and material: two loops for nylon, three for carbon.
II
12-hole bridge
How the 12-hole bridge works
There are two holes for each string. The goal is to create a steeper break angle over the saddle for better downward pressure. The lower row of holes passes the string through to the front; the upper row is used only for tying — the string loops back through it to form the knot.
Treble strings
Two-hole method
Lower hole, then upper
Pass the string through the lower hole, then make a loop and feed the string back through the upper hole. This creates the steep break angle over the saddle that characterises the 12-hole bridge design.
Ball end and final knot
Create a small ball at the end of the string to prevent slipping — a simple knot works equally well. The finished knot secures the string firmly against the bridge with no risk of pull-through under tension.
Bass strings
Wound strings
Bass knot
Start the same way — pass through the lower hole, loop back through the upper hole. Hold the loose end firmly in place and tighten. For wound strings, this single loop is sufficient.
III
The headstock
Threading the post
Position the tuning post hole vertically and pass the string through from top to bottom. Create a locking loop — the string passes under itself so the first wind locks the string in place and prevents slipping as tension builds.
Tighten and trim
Tighten the string while keeping the loop locked against the post. Once up to pitch and stable, carefully trim the excess string. Leave a short tail rather than cutting flush.
Three to four turns of winding are enough. Excessive winding adds no benefit and can make future string changes more difficult.
There is no need for excessive winding — 3 to 4 turns are enough.