Radiused Nut Slots, Is It OK to Flatten Them

[Commodore 64***]

I hate radiusing the bottom of a nut. Most Fender guitars I work on are 9.5 radius, and the pre-radiused ones are 7.5. Not to mention that the pre-radiused nuts are ridiculously marked up ($3.00 vs. $7.00 for bone at Stew Mac).

Why is the nut slot radiused?
Can I just take a file and make it flat?

[kiteman]

I think you'd want the radius of the slots to match the radius of the frets so the strings are of equal height in relation of the bottom of the strings to the top of the frets.

[Commodore 64***]

I agree, but that's easily accomplished when slotting the nut. I'm talking about the bottom of the nut. I don't see any benefit to the bottom of the nut being radiused. Which begs the question, Why does fender radius the nut slots (thus requiring a radiused nut blank)?

[kiteman]

I don't know why but you could plane the wood so it's flat and use the flat bottom nut. The question is will it go into the truss rod channel?