Removing a nut from a Gibson guitar or bass isn’t hugely difficult but there are a couple of things that can trip you up and cause problems.
Find out how to do it safely…
OK, on this one, we're assuming you have a Tun-O-Matic bridge. This is what's generally installed across a huge swath of the Gibson range and it's almost certainly what's installed on your Les Paul, SG, Firebird, Explorer, 335, etc., etc. There are a couple of styles of tun-o-matic but the basic operation is the same. If you've got a wraparound-style tailpiece bridge, check out that article.
The adjustment screws can be a bit fiddly to access so be careful. Try not to damage your strings, your guitar top or the screw itself. Use an appropriately sized screwdriver (usually a small-medium flat-blade)
First up, though, let’s recap the prerequisites.
The rest of your setup must be right for you before you start. Intonation is the last thing to set so get your action, relief, nut and pickups sorted out first. You should have fresh strings (of your usual gauge and brand) installed, properly stretched, and tuned up as normal.
Remember, too, always check intonation and tuning with the guitar in the playing position (i.e. not lying on a table or counter but upright as if you were playing it).
The basic theory is this:
Every now and then, you might come across a Gibson that just will not intonate. Sometimes, the bridge is just in the wrong place (seriously—it happens) and, even if you flip saddles, there isn't enough travel to intonate. If you bought it new you can try warranty service. There are also some after-market tun-o-matic bridges that are wider and might allow extra travel if you can find one. And, as a last resort, you can have the original holes plugged and the bridge re-mounted. It's a pain but it's occasionally required.
The big quirk on these bridges is the reversed saddles. It might be helpful if I expand a little on the bridges themselves.
While there are any number of slight variations, there are two types of bridge fitted to most Gibson electrics. They are the ABR-1 and the Nashville.
The ABR is the original bridge. Usually, you can look at an ABR bridge and see that two or three bass-side saddles are installed ‘backwards’ (with the sloped or angled side pointing towards the neck). This is to make up for the fact that there is insufficient travel on the intonation adjustment screws to get these strings to properly compensate. By flipping the saddles, you can get a tiny bit more compensation before the saddle hits the back of the bridge. Essentially, it’s a cludge. It’s a workaround.
Gibson tried to address the issue by introducing the Nashville tun-o-matic bridge. This bridge has a little more travel and it generally intonates without any saddle-flipping. Of course, as with many changes made by Gibson, lots of players complained they preferred the original and so you’ll find a mixture of Nashville and ABR bridges installed across Gibson models.
The ABR already has some saddles flipped. The Nashville doesn’t. However, on either bridge, you’ll occasionally have to flip one yourself. Sometimes you’ll be at the end of the saddle’s travel—it won’t go any farther back or forward but you’re not quite intonated. Flipping a saddle might just get you where you need to be.
On the ABR, it’s pretty easy (if a little fiddly) to do.
On the Nashville bridge, you can get lucky and find a model that the screws just ‘back out of’ but most often the screws are ‘captured’ by a clip of some kind.
This may be a circlip (C-clip) or wire clip. Getting these off to flip saddles is possible but it’s a lot of hassle—especially putting them back again. The wire clip in particular will probably need to be replaced afterwards.
Approach this with caution and talk to your trusted repair person rather than forcing the matter.