Screwed up a nut - How to fix?

I cut a tiny sliver from a guitar pick and super glue in the slot. I've done this a couple of times and works perfectly and easy to file if you still need to go deeper after gluing it in.

 

Before we even go there.....check the truss rod relief......put a capo behind first fret, push down at last fret, and frets 7-10 should have just enough room between the low E and tops of frets to slide a thin business card through.....check that THEN report back on your nut situation....

 

If you have to shim the nut, the best way is to cut a shim from the paper envelope some strings come in. Wet it with crazy-glue and apply that sucker like a model-airplane decal. I shimmed just the bass side and it worked too, but I smoothed it after it dried.
You can also fix a slot by crazy-gluing in a shred, shard or dusting of scrap nut material and smoothing the seams after it dries.
The pros redo it from scratch, but us tinkerers ain't got the patience.

 

You're checking the relief measurement, it's not checking to see how it plays there......it's last fret, 21 or 22 - not 17......and distance doesn't measure any string except distance between tops of frets 7-10 and low E.....

My guess is you have more than .015" relief which is not a good sign, it means the nut slots were filed too low because the truss rod needed tightening and the whole guitar was not checked for setup before hand....and it probably would have had perfect nut slot height had the relief been set.....

 

If your slots are a little low, the best way would be to shim it and then adjust the other slots to suit. If you don't want to remove the nut, then using some bone nut dust and thin superglue can make a suitable filler - here is how I did it some time ago, the repair is still OK.

https://www.strat-talk.com/threads/squier-jv-neck-restoration-project.20417/page-2#post-135055

 

If you shim the nut, you will have to lower all the slots.
Might be good practice.
Some baking soda in the slot, then some water thin super glue can be considered a permanent fix.

 

Only file the slot a tiny bit at a time; with lots of playing in between.

Once you're able to fret at the first fret without the note going sharp; STOP filing.

 

I once had some low slots and used the baking soda/super glue method. There is a video of Dan Erlewine explaining it on YT. Never had the same problem again, I'm still using the same nut. When you file down the solidified baking soda on the slot, give it a little down slant towards the headstock. The highest point on the slot should be where the string enters it coming from the bridge.

 

if you totally screw it up then this

 

But don't make it TOO much of an angle!

If the string is at too steep of an angle it puts too much downward pressure on the plastic right where the string overhangs the nut, and this extra pressure can end up wearing/cutting the nut down at this point, leaving it cut too low after a decent amount of restringing, tuning, playing.

I learned this lesson the hard way....

Make the angle just enough to make certain the string is vibrating at the edge of the nut.

 

It happens.

Believe me, the next time you do this you'll get it right!

 

i fix nut slots with super glue and fine bone dust, or corian dust. i drop glue in the slot and drop dust on the glue and then glue on the dust.

then i re-cut the slot.

 

The baking soda is not just for structure... it's a catalyst.
The down side of that is, if you fill the slot, the glue can harden before it completely penetrates. Then there is just powder on the bottom.

 

As for getting the slot just right then finding it too low...it has happened to me.
I have no idea how.
It's weird and it sucks.
With bone, it could be a void in the bone
It could be dust left in the slot.
The only thing for sure is, it's frustrating.

 

i work fast and with a super magnifier to make sure it is going to become one with the nut, but you are correct, it will go wrong if they do not all bond together.

 

I've used a thin slice of 1200 wet dry sandpaper under the nut to shim it up. If filling a nut slot, I use thin layers of CA and graphite dust for graphite nut and thin layers of plastic dust or baking soda and CA for a plastic nut. Key is a few very thin layers of dust with the smallest drop of thin CA. then you have to smooth sides of nut and re-file to perfection.