Planing to restring and detune my guitar, how to make nut string slots wider?

[NoiseNinja]

So I am planing to get a set of strings with the gauges .012 - .016 - .024 - .032 - .042 - .056 and tune them to D standard tuning (the G string being wound), compared to my current set .010 - .013 - .017 - .026 - .036 - .046 tuned in standard E tuning, my guitar being a 24,75" scale Epiphone SG Special.

I checked up on it and the tension of the strings I intend to buy is pretty balanced actually, though a bit higher tuned to D standard tuning than that of my current strings tuned in E standard tuning, though that is fully intentional from my side, and actually the tension of the new strings will still be no more than about similar to if I had strung my guitar with a set of gauge .011 to .049 strings and tuned it in E standard tuning.

Now here comes my issue, as I kind of suspect the current string slots in my guitar's nut not being wide enough to accommodate those kind of relatively thick string gauges, and I expect, almost for certain, at very least the gauge .056 low D string being too thick to sit properly in the nut string slot.

But as I don't really want to invest a small fortune in a proper set of nut files fitting the new string gauges (I could have a guitar technician fix the issue much cheaper than what such a set would cost me) I was wondering if there is any, preferably relatively easy and ready available, cheaper alternative options for making the nut string slots slightly wider to fit these new thicker gauged strings?

Like could I for instance cut out a thin strip of fine grained sandpaper, and then, after fitting it down in a nut string slot, kind of bending it around each side of the nut while holding on to each end of the sandpaper strip, then pulling it back against the side of the nut string slot, rub the sandpaper back and forth until the nut string slot has been sanded to the desired width, or wouldn't that work, and if not what could I possibly do instead then, perhaps very carefully scratch away nut material from the sides of the nut string slots with a small hobby scalpel or razor blade, or..., anything?

In case it being relevant I should properly mention that the the nut on my guitar is made out of some sort of hard plastic material.

 

[donepearce]

You can try this, and it may work, but don't hold your breath. Setting nut width is quite a demanding job. It isn't just the width of the slot, but the shape of the bottom of the slot that matters if you are to avoid pinching. At the very least get some abrasive cord in several sizes from Stewmac so you can polish the result.

 

[Wild Bill212]

You can get a set of files for $60 @ Philadelphia Luthier Supplies dot com....they're not Pro files but, But ,BUT... they hav lasted me years and I cut all my own NUTS !
and, BTW, forget stew-mac !Save your $$$. Philadelphia Luthier Supplies has everything Stewy has, for much less !Besides much else, I got a hand held Fret-Press w/12" Radius Caul for less than $90..Stewy wants $325 for the same thing !

 

[Von Trapp]

Use strings as files.

 

[donepearce]

Use strings as files.

Nuts have to be hard enough that strings really don't do any filing. And of course if they do, that's how you end up with pinching strings.

 

[Von Trapp]

I've done it just fine, and of course you have to use larger strings for the filing then you actually put on.