I sure can't figure it out but I'm NOT very bright.:lossinit: The reel is a 3500B that can hold 305 yards of 8lb line.

Problem is I want to back up 20lb Spiderwire with 17lb big game. How could I ever know how much of the backing to put on to use up the entire spool (150yds) of braid on top of it.
$35.00 bucks each for two new Baitrunner spools. Could have got them a little cheaper on line but I Petes not in business I won't have a place to yak and but chunking meat...

Best way is to wind it onto a second spool inside out . You cut the backing when the spool is full where you like it then rewind onto the second spool backing side in and it comes out perfect.

Saltheart.... That is so simple. I swear that even though I have extra spools I never even thought to reel the braid first onto one spool followed by the backing and then just reverse the process onto a fresh spool!!:smash: Your the greatest.

You should be a moderator!!!!

Holy crap am I an idiot. I have been trying to figure that out by doing the math. I usually come close but not exactly where I wanted it. That idea makes much more sense.

Frankiesurf I was trying to do the math as well and can't even balance my check book. My 16 YO boy even laughed it off when I asked him to figure it out and he is a little math genius.

Sigh... Age is gonna be the death of me. :scream:

Best way is to wind it onto a second spool inside out . You cut the backing when the spool is full where you like it then rewind onto the second spool backing side in and it comes out perfect.

I used to do it that way when I wanted it perfect.. Now I don't worry about perfect much so now I just put enough backing on to cover the spool a few times..

I've gone to electrical tape on the empty spool, and eliminating the backing. As long as I lay the initial couple dozen turns of braid carefully, with proper tension, covering the spool base with a couple layers, I have not had any issues. I use PowerPro, and some Suffix.

I'm right there with ya on the electrical tape method.

I like the electrical tape idea but a 300yard spool of 50lb/12lb diameter Power Pro won't fill a 4500BTR spool. Do they make a larger filler spool for the average Joe??

I guess it would fill a 3500BTR with no problem but I doubt I want 50 lb on a 3500. This is gonna be my first time trying the braids and I never minded a nice fresh Mono so I am really not sure what I am trying to gain. Sometime I get so confused.:spin: