After careful thought, and some study as to how much the B string would come in handy, I am now very seriously considering tuning my Frank Bella ESP Ltd. to BEAD. I have a spare set of fiver strings, so all I would have to do is file down the nut to accommodate the thicker strings.
I’m convinced I can live without the G string, and if needed, can use frets 5-17 on the D string in it’s stead.
Questions:
What kind of file do I need for the nut? Is it something I can order on StewMac?
In addition to filing the nut, is there anything I would need to do to the bridge etc?
Are there any negatives to doing this (cons)? The pros I see are the benefit of the B string without the added heft of a 5 strings.
Yes, I noticed that . . . You could actually order single files, though. You probably only need the B string sized file, but you’d have to confirm this with one of the experts
In a pinch you can use the string itself as a file. The roundwound surface provides a very dull file like surface.
So if you’re only doing one string you could carefully file the nut using the string itself. Just be aware of the angle of the slot. You want to copy the same angle as the others. There are videos about this. I’ve done it but only on a cheap plastic nut. I don’t know if it would work on say a TUSQ nut.
I went with a zero fret when I went BEAD; in part because with the zero fret the nut sort of just holds the string in place, and if I don’t have the nut filed perfectly it’s okay.
I went to Walgreens and got emory boards (little ones) to file the nut. Also bought a spare Tusq nut in case I botched it.
Something to consider is string tension. There’s a lot more of it with the heavier gauge strings of BEAD. I’m not sure I would do it on a skinny/thin neck.Your preference for flats might limit your choices…
The B string on my Jazz is not tensioned heavily at all. I haven’t seen any issues with the neck either. It had a lot more tension on a 35" scale; one of the things I consider a con is the tension on the B. Shorter scale lengths have less tension, see a short scale bass for example
The G is under more tension, and this is how multi scales work. Having a G scale at 33.5" and and a B at 35+" all the strings will have the same tension. That’s the theory.
But to Pam’s concern, without the G string there will be less overall tension on the neck actually.
That would look SICK with some DR Coated Red Devil RED strings on it.
IDK if you find those too painful to play or not, but I think they feel pretty nice.
Actually BEAD usually has slightly less tension that EADG. Much of the tension in EADG is from the tighter D and G strings, The B string is tuned lower and tension is not as great. As you can see here:
Tension for a D’Addario standard .045-.130 set highlighted there, tension on the G string is significantly more than the B string. So much so that you can even go up to a 0.145 B string and have less tension than EADG.
Correct.
I filed my nut with a cheap round diamond file I had lying around. Worked perfectly. You just need to be careful and go slow. Maybe buy a couple nut blanks?
Unless you plan on doing this to many, many basses, I wouldn’t waste the money on the nut files. YMMV.
You may need to widen or replace the bridge saddle with a wider one, but probably not. I didn’t.
The only negative is the lack of the G string. There’s a whole ton of positives around that B string. The bass loses five semitones in the top end and gains five in the low end. Whether or not you like it is up to you
You will need to relearn (or re-remember) the fretboard like it’s the top four of a 5-er.
You could actually order single files, though. You probably only need the B string sized file, but you’d have to confirm this with one of the experts 
