One of my strats has a "buzz" on an open G string vs. holding down the first fret. I think it may be traced to a possible too deep of slot. Is there any other fixes such as super-glue, other fillers, etc? Or do I have to get a new nut or raise the old one? Thanks!
For a truly temporary fix you can put a piece of paper in there. I actually have a guitar that's been like that for several years (not in regular rotation or anything) as I've been too lazy to replace the nut (or have someone do it for me).
Take some black electrical tape and place a strip on the neck side and the tuner side of the nut high enough to create a dam on the nut slots. Get a piece of similar material (bone if your nut is bone, plastic, etc) from a local shop tech if you can. File some dust from this and pack it in the slot using an X-acto knife. Then get some water thin super glue from Hobby Lobby and their Wipit Tips (long skinny extensions for the bottle tip so that you can control the volume of super glue that comes out). It might be good to get some Super Glue Accelerator while you are there. Place a small drop of water thin super glue in the slot and then take another Wipit tip and dip it in the Accelerator and place a drop of it on the slot. It will harden instantly. Remove the tape, and if it sticks to the glue scrape it off carefully with the X-acto knife. Then get a correct fret file for the slot and file it.
If you don't wanna drop coin on the file take it to a local shop (ask permission from the tech first) and ask if you can file the slot there at the shop. Offer him a few bucks as a tip if you like. Or, you can go to Home Depot and buy the cleaning kit for welding toch tips. They are like tiny files.
A last option is to take a G-string (not your local exotic dancer's either) and us it as a file. You can glue it to a popsicle stick or pencil and use it as a file, or take a long enough string and wrap it around your fingers like flossing your teeth and try to file it down. The last option is difficult. B/c I like to build things, I drilled a hole in two wooden dowels to run a string through and wind it to create handles for a "wire saw" using wound guitar strings for cleaning fret slots. It also helps with abrasive cord for nut slots.
Sometimes this lasts a lot longer than you expect. I did it on one of my cheaper strats and have not had to mess with it in over a year, and play this guitar a lot while noodling watching TV. It doesn't affect tone, no matter what anyone else says. If they can hear it, then they can never make fun of Eric Johnson's ears.