Tapewound string for high-F (7 string bass)

Use a plain steel... La Bella made a few nylon wrapped steels but they said they aren't going to make anymore.... Sigh

 

Kalium don't.
Perhaps try a guitar string, many guitar strings are just long enough to reach the tuner post nearest the nut on a bass. Thread an old detached bass ball-end onto the string to make the ball end larger.

 

Without knowing the gauge and scale length nobody can answer your question accurately.

 

Knowing the scale length of the instrument would indeed help.

The .026w or .028w from the La Bella black nylon "Regular" or "Light" Jazz Tape sets for archtop electric guitars could be the ticket:
La Bella Strings
La Bella Black Nylon Tape Wound 800R Electric Guitar Regular 10-46
La Bella Black Nylon Tape Wound 800L Electric Guitar Light Gauge 12-56
La Bella 800R Jazz Tapes Black Nylon Tape Wound 6-String Electric Guitar Strings
La Bella 800L Jazz Tapes Black Nylon Tape Wound 6-String Electric Guitar Strings
HOWEVER!:
1) the 36" winding ball-end to silk needs to be enough for the bass, as mentioned - you *might* try and remove *a little* silk at the nut side, but too much and the tape will unravel;
2) I can't guarantee either string will not bust at the target pitch. The .026 (a D string in the -R set) normally operates at a minor sixth's worth of tension less than it would in the role of a bass high F. The .028 is closer to its normal operating tension: tuned to F3 on a 34" bass it would be "only" a minor third tighter than it is on a guitar as a G (that actually means almost 50% more tension, hence the sarcasm-quotes).

The high E of a La Bella bass VI nylon set, either black or white, is .026 in gauge, similar in winding length (~35.5") and also might work (it too would be 3 semitones tighter than factory-intended):
767-6B Bass VI Black Nylon Tape - 26-95 | La Bella Strings
767-6W Bass VI White Nylon Tape - 26-95 | La Bella Strings
Of course, bass vi sets from La Bella are almost 50 bucks apiece.

Galli and Pyramid also make black nylon tapewound sets for guitar, but if you're US-based those are harder to find and probably dearer. I use Gallis for the middle strings my 30" bass VI thing currently, but I'd gotten the 14-67 set so no wound string under .03 - I just use a (metal) flatwound as my high E.

 

Isn't a high F around .020"?

 

I have bass vi tapes available... They are too short for a long scale electric bass

 

Whoa. Tuned to F, at 35"? Should be over 70lbs of tension, assuming it doesn't break before reaching pitch. Don't recommend it. I have used, on my VI, and am deeply in love with D'Addario Chromes for guitar, and my suggestion is to look for a single .02, or a .022:
D'Addario Chromes Flat Wound Electric Guitar Singles from Guitar Strings Online
38" long, small ball-end to end of flat ribbon.

Mind you, a plain string would work just as well, but as far as me, I find thin guitar flatwounds noticeably more durable under my acidy-sweaty fretting hand. YMMV. But yeah, I wouldn't rule out plains if I were you instead of me...

Ay. Noted. Only case in which a Gibson three-point bridge would have helped (very little distance between ball-end anchoring and saddle)...

 

If I was in your situation, I'd purchase a 6-string set of La Bella Jazz Flats White Tapes bass strings and buy a plain steel high F.

 

Yes. That's why most people use an unwound string.
Wound strings that small have a tiny core that is easy to break.
Both people I know who gig with high-F strings go through two or three F's during the life span of the other strings in the set.

 

Anyone who purchases a 7-string set I generally suggest getting 6-string sets and a bunch of plain steel strings as you will change the plain more often than the others... I met a guy who purchased 144 7-String sets from a big name manufacturer and I said to him, why didn't you just buy a bunch of singles... His face went white... Needless to say he is very happy he met me now.

 

I've had good luck with the SR2000 .022 wound strings as far as breakage. Personally the plain F strings just never felt right.

 

If you try a flatwound the D'Addario Chromes guitar flatwounds .020 or .022 are long enough for the tuner post nearest the nut (as long as you top-load). I use those on my fretless bass.
A bass .032 will not tune to F and will either break or be unplayably tight.