I've been practicing wrapping for the last few months...I'd keep rewrapping with hinerimaki, making sure to alternate sides and finished off with the endknots...but after one unfortunate decision to snip off some cord, i also ended up with too little cord. So i'd always make some kind of halfassed improvised knots that would hold for a while as the lack of cord and not using any glue at all usually, made it hard to achieve lasting hold and the kashira would come sliding off after rigorous cutting.
So coincidentally, just today i decided to experiment with katatemaki battle wrap. I mentally calculated that there should be enough cord. After finishing the katatemaki part, i used the remainder of the short cord i snipped after the first hineri diamonds, to continue with the bottom hineri and finish off.
I then used a paperclip and some hempstring to make a needlethingy, and tied some improvised knots and halfhitches. Looks a tad messy and the knot not quite as symetrical and slightly too pointy, however, it seems to hold really well, and i can't imagine it coming off by itself soon.
So you can learn how to wrap. But i wouldn't unwrap unless you already have a good idea of how to go about it. Can't you just wipe it with a wet cloth or simply moisten the dirty spots and scratch them off gently. Don't know just how dirtly your cord is? If you learn how to wrap, you can order as much cord as you like and in any many colors.
When i was a youngster and once unwrapped one of my swords without knowing how to rewrap, i resorted to doing the best i could and taping over everything with hockey tape then electrical tape- terrible i know. Got me thinking about different grips. I was even thinking of using tenniswracket grips. That would make for interesting tsukamaki too.
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