I want to have the nut depths just right and wonder how the slots are cut to the point.
How can I prevent cutting them too deep?

It´s a bit annoying lifting the string - cutting a tad - then slipping the string in again - then lifting it out again ... and so on.

Maybe someone can give me a hint how to prevent the cuts being too deep?

The question is about the nut of my Rickenbacker 360-12 Mapleglo (2013)

Just some advice, if you're not experienced in this procedure you might be better off taking it to a guitar tech. If you cut too low or too wide your intonation could really be thrown off.

You're doing the right thing -- just do it when you have nothing else to do and simply enjoy doing it. Experience will allow the process to go faster as you learn how much material you can remove at each adjustment. ("Haste makes waste."). But if you're in a rush, it may be quicker actually -- and safer -- just take the guitar to a tech, as was suggested. Use a lubricant on the nut afterwards (e.g., Nut Sauce) and you will be trouble-free for years to come.

Otherwise, having a good set of files will help the most, and knowing how to use them; width of nut slots for respective string sizes, slope of cut. Study, watch some YouTube videos, go to the Stewart-MacDonald web site and watch a video there/read tech support.

Thanks for your suggestions!
I´ve got a set of nut files and I looked at the advices of Stewmac.
So I bought a couple of feeler gauges today.
I will use them the way Dan Erlewine shows in a video.
But...I still have a spare uncut saddle.

Sounds good! (Dan's the Man) Have fun.

I'm not trying to discourage you from attempting it, nothing ventured nothing gained. It's just a somewhat delicate procedure, watch the video and take your time. Cheers, Ricslinger.

Yep, that´s why I asked

On my acoustic guitars I have all bone nuts and saddles, even on the 12-strings. They are wider than the Ricks.

On my 360-12 I have tried bone, but since I wanted the nut to be a tad wider than the original one, I now prefer Tusq. Bone tends to be more brittle , especially at the ends.

I've been doing/redoing the slots on my 360/12 slowly, and have finally gotten them to within a couple of cents in tune on the 1st fret (had I known how far off they were, I would've probably removed the nut and sanded the back, instead). I have the Peterson Strobe tuner app on an older iPad, it's great for setting intonation.

I didn't understand the earlier post about filing too much making your intonation go off - the only risk I see is that past a certain point, your string will be hitting the 1st fret when it should be open (unfretted). Then it would need to be refilled (crazy glue/baking soda or a new nut), and start over.

Stew Mac will sell you this gizmo, if you want a more exact or controlled way to do it.

http://www.stewmac.com/Luthier_Tools/To ... e_Set.html

That gizmo is so cool, so smart.

I basically meant the intonation of that single string could be thrown off, not the entire guitar. Too low or high of a nut slot can cause sharp or flat notes when fretted. At least this is what the tech at the local store indicated.