Why? Did the cotton balls wick better? Or is it just easier to deal with since its sterile and ready to go? I have both (pharmacy grade balls and using Peaches and Cream 100% yarn).
I'd love to start rewicking my own coils... and if I can eliminate the need to get wicks, a long roll of Kanthal will go a LONG way.
With the cotton balls, do you roll (not twist) it a bit or just bunch it enough to get a wick-like structure? I know its a feel thing, but when it tried cotton ball for a top wick, it kind of puffed up a bit too much inside the coil and probably choked things a little bit.
I've used cotton cheesecloth. It's already stranded. I just cut a section out, roll (not twist) it to the desired diameter and go. It also swells a bit, but so far so good. As for diameter, it's more of a feel thing than a measurement thing.
In fact, the first thing I do when putting a factory new coil in one of my BCC's is pull out the silica flavor wick and replace it with my own. I like it a little longer than what comes stock from the factory, and the cotton just seems to wick better.
I'm not a rebuilding expert. I've only done it a few times to show myself that I could. I've decided to just keep a steady stock of replacement coils in the pipeline because it's just not economical for me to rebuild every coil (my time is worth a lot).