How to Clamp a Guitar Bridge

The bridge on your acoustic guitar is glued in place.

When building an acoustic guitar or replacing a bridge on an existing acoustic guitar, you must clamp the guitar bridge in place while the glue dries. An acoustic guitar bridge is manufactured out of wood, usually ebony or rosewood, and glues to the surface of the guitar’s body. Clamping the bridge is relatively easy; however, you need to make sure you place the bridge in the correct place so the strings line up and the guitar will intonate correctly when played.

Things You'll Need

• Precision ruler
• Wood glue
• 3 deep throat C-clamps

Instructions

1. Locate the center line of the guitar. To do this, measure the width of the neck at the heel or where the neck rests over the body. Divide the width of the neck heel in half and then place a pencil mark on the face of the guitar, in front of the neck heel, to denote the center of the guitar.

2. Measure the width of the guitar bridge with your precision ruler and then divide the number in half. Place a small mark on the center of the bridge with a pencil to denote the center.

3. Measure from the front of the guitar’s nut to the 12th fret with your precision ruler. This gives you the scale length of the guitar. Measure the same distance from the center of the 12th fret to the guitar body. Place a mark on the guitar body. This is the mounting location for the guitar bridge.

4. Apply a thin sheen of wood glue to the bottom of the guitar bridge and then place the bridge on the guitar. Center the bridge from left to right and then place it over the mark that indicates the scale length.

5. Place a piece of scrap wood on top of the bridge. This keeps the clamps from marring the wood.

6. Slide the bottom leg of three deep throat C-clamps into the sound hole and then line up the top of the clamps with the wooden block on the top of the guitar.

7. Position one clamp at the right end of the bridge, position the second clamp in the middle of the bridge and then position the third clamp at the far left of the bridge.

8. Turn the threaded handle on each clamp to clamp down on the block located on top of the bridge. Do not over tighten the clamps. If you hear wood cracking, stop tightening. You do not want to crush the fibers of the wood, as this will weaken the guitar. Allow 24 hours for drying before you remove the clamps.

References

• Stew Mac: Scale Length Explained

Resources

• Stew Mac: Soundhole Clamps