How to Shim Up a Nut on an Acoustic Guitar
By Fret MD | March 9th, 2009 | Category: Acoustic Guitar, Tutorials |Remove the Nut
Now the first thing you’ll need to do before you shim up a nut is to remove the nut. In order to do this, you’ll need a soldering iron and a wet paper towel or rag (a cotton rag or cloth would be best - avoid highly flammable and/or synthetic materials).
1. Remove all of the strings from your guitar or pull them to the sides of your neck so that the nut is exposed.
2. Heat up your soldering iron and wet your cloth or paper towel.
3. Once your soldering is hot, place the damp cloth on your nut, being sure that the damp part of the cloth covers the joint where the nut makes contact with your fingerboard.
4. Now use the soldering iron to force steam into the the space between the nut and the fingerboard, moving the soldering iron and cloth back and forth from one end of the nut to the other. (The steam will soften the glue that holds the nut in place.)
5. Use a scribe to seperate the finish between the nut and the headstock overlay. Note: Sometimes the finish that was used on the headstock will be stuck to the nut. If you don’t use the scribe to separate the nut from the headstock finish, you could cause some damage to the headstock finish.
6. Use a block of wood or plastic block, and a mallet, to tap the nut out and remove it.
How to Make a Shim
Now that the nut is out, it’s time to shim it up. First, clean up the bottom of the nut by passing it over a flat block or table with 220 grit sandpaper then clean up the slot where the nut was sitting with a flat file. (Some players are purists and reject this step on principal. Others don’t mind. If you can’t bare the thought of placing a shim under your nut, then you’ll need to replace it.)
1. Cut the shim out and attach it to the nut. If you’re using an adhesive back as your shim material then this is very simple process. You just remove the backing from the acetate (make sure its over sized) and and stick it to your nut. Transparent pick guard material works well for this job. If you’re using wood, you’ll need to glue it in place and let it set overnight.
2. Use a razor blade, shave off any excess plastic and make sure your shim is flush with all sides of the sides of the nut. If your using wood, it should match the neck (usually Mahogany). Again it should be over sized before you glue it to the nut. After it dries, chisel, then sand the wood flush with the nut.
Replace the Nut
1. Place a very small dab of glue on the face of your nut, in the center with tightbond or any other aliphatic resin type glue that your local hardware store carries.
2. Carefully slide the nut back into place and and wipe away any excess glue that overflowed onto the fret board with a damp cloth.
3. Restring your guitar.
4. Assess the height of your strings with a feeler gauge.
5. Hopefully, if things worked out right, your strings are either just right or a little too high. If some strings are still sitting too low then your shim wasn’t thick enough and you’ll need to remove the strings again and raise the nut a little higher (better a little too high than too low this time; you don’t want to have to keep removing the nut and shimming it up).
- If your strings are sitting at the right height, then you’re done with this step and can continue your setup.
- If some strings are too high now, then you’ll want to file down your nut slots to get them to the right height.
