My cotton always break apart after 1 day use and it gave me a very unpleasant vape. Burn taste keep coming if i chain..sigh. Cotton problem? I'm using brand Coil Master, Japanese Unbleached Organic Cotton btw. 

It's falling apart? Is it burned? Do you have any hot spots in the coil, or wicking issues.. Or maybe tour wattage is too high? What tank are you using, what build do you have, what mod are using, and how many watts?
Are you sure you are cutting it the right way? With japanese cotton, it's woven in one direction. You have to cut it with the grain so to speak. Also, are you wetting it with juice where it sits in the coil before you fire it?? If not, you could be burning it out.
Lookup the pancake method of wicking, it sounds like it isn't wicking right. What vg ratio is your juice? My lemos didn't wick well over 70vg so I dremeled the deck channels slightly.
How tight are you cranking down the top cap? At 50vg you shouldn't have any wicking issues. The tighter you tighten the top, the more the bottom of the gasket compresses into the juice channel, to the point of blocking it off.
My cotton doesn't break apart after a week of use unless it wasn't wet enough and burned. That's why I'm leaning towards a wicking problem. When you fire your coil with no cotton it's all even right? No dark spots or anything?
Is your cotton burned when you take out the old to re-wick? I don't have this problem. I'm using rayon though, so it's probably behaving differently than yours. I just can't think of why it would be breaking up.
Next question, what size coils are you making? AS IN, what are you wrapping your coils around to twist them?
If you are making MICRO coils, you are just putting too much cotton in it, the juice isnt wicking like it's supposed to and it's causing the center of the coil to heat up the cotton too much in the center because the juice isn't making it.
That is SO odd.... Is this the first time using this type of cotton? Or have you been using it for a little bit and just realized the problem?
Hmmmmmm. Very very odd. You should try making a new coil or atleast thoroughly cleaning the coil you have now.
That happens in my Reo atties sometimes when I forget to squonk. You're dry hitting the cotton and burning it through inside the coil. Fix your liquid feed issue and it'll stop.
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