Thank you all for being super helpful :-)
I went with the baking soda and super glue

The G and B-string could also use some adjustment, but for now it's playable.
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Thank you all for being super helpful :-)
I went with the baking soda and super glue

The G and B-string could also use some adjustment, but for now it's playable.
I think the classic method is bone dust mixed with glue. Though its not as good as a new nut. Here's a thread. Sounds like bonding to plastic like nylon is more problematic.
Nice thread, really informative.
Anything you put in those grooves is going to be, by necessity, softer and less durable than the nut itself, so whatever you decide, you should still think of it as a temporary fix. Consider a material that produces as little friction as possible. A shim will move around and possibly fall out. Another poster mentioned bone dust/epoxy mix and I honestly don’t have a better suggestion.
Most music shops keep a luthier in a gimp-style storage crate in the back room. Always a good investment to have one install and set up a new nut if you can do that. That way you know your action and intonation were set up properly.
Yes, this it definitely a temporary fix :-)
Classic repair shop trick is baking soda and super glue, just tape around the nut so you don't fuck up the fretboard, when it dries in like 15 minutes you can file it back down
Thanks for the reminder to cover the fretboard :-)
OP used your advice and fixed his nut, but I thought I'd leave this video here for anybody else who runs into a similar problem.
why would you make a new nut when you can save your old one like this? in minutes!
are you happy with the level of the strings relative to the first few frets? if so, maybe you can just sand down the nut from the top.
I'd like to get as high as possible, I want to use it as a designated slide-guitar and I'm trying to avoid the rattle.
Sorry so late. You can likely fill the "slits" with a mixture of baking soda and superglue as long as you don't mind the color mismatch, and then file out new ones to the correct depth. Epoxy will just give you a bad day