To glue or not to glue?

[JiminRussia]

I am not a Luthier, but I play one on the internet..... I want to replace the nut on my mando and I am considering doing it myself. I already know that it takes some special files to cut the string grooves and am willing to buy those. I can use the existing nut as a pattern for the spacing etc., but how is the nut held in? Is it usually glued and if so with what kind of glue or is it just a friction fit in the slot for it?

[sunburst]

It's usually glued.
It should be glued to the end of the fingerboard rather than the rest of the slot. That way it stays where it belongs...where the strings are in tune (more or less).
You can use titebond, hide glue, super glue, even epoxy. The trick is, in my opinion, it should fit the slot well but not too tight. It only takes a couple of spots of glue to hold it that way, and it can be removed fairly easily.

Another school of thought is that it should be a little loose in the slot and glued very securely to the end of the fingerboard. Then when it comes time to remove the nut, a "nut knocker" will pop it loose from the end of the fingerboard and it has a little space to move. The idea is it won't tip and cause damage to the headstock overlay.

A nut knocker is a piece of hard wood that you put against the edge of the nut, the edge toward the bridge, and tap with a hammer to shock load the glue goint and break the nut loose.

Anyway, I've accumulated several emergency methods of removing stubborn nuts over the years, so there is no excuse for instrument damage from nut removal no matter how it was glued in.

Sorry for the long answere to a short question.

[Chris Burt]

If the nut fits well, not too loose and not too tight, a tiny dot of glue is all you need. As you size the nut, you'll know it fits well when you can slide it firmly but easily, from side too side, between the fingerboard and the headstock veneer. Too tight and moving the nut theatens to chip the wood or the finish of the headstock veneer. Be willing to make more than one nut.

Chris