Kayfun v4 burnt wick

[Caterpiller]

I've been having very mixed results with my kayfun v4.

It's my first rebuildable, so I'm sure this is due to poor wicking or something similar.

My latest 1.8 Ohm, 6 wrap, 30g coil tasted a bit off after the initial pulls.

So I took out the deck and could see the problem, hoping some of you can provide the solution.

I'm using cotton. With the wicking just touching the deck as seen in a few videos.

The coil is 2.4mm and I put a fair amount of cotton through the coil, enough to have some resistance when pulling through, but without jamming in.

On inspecting the wick after about 30 pulls, over four or five poor tasting sessions, I noticed that while most of the wick looked very moist and in fine condition, their was a dark (burnt?) patch directly where it made contact with the top of the coil.

Most likely reason? Anyone? I've no idea if I'm using too much cotton or not enough.

I should say I never went over 8watts, kayfun v4, air flow completely open and unrestricted. Coil approx 2.5mm above air hole.

 

[DaveP]

I use eight 3mm turns of 28ga Kanthal to create a 1.8 ohm coil. Sometimes, after vaping on a wick for a couple of day I see a spot that looks burned, but it usually washes out clean, so it's probably just juice that caramelized.

IMO, wick sizing is critical to efficient operation. The entire coil needs to be filled and the wick ends need to constantly touch the deck without stretching them. Almost touching or just touching could be a problem. I use a hypodermic needle to press the ends down and ensure they touch all the way across. That's just to make sure they are touching without creating stress and leaving the top of the coil open. You don't want to compact the wick, just get the ends down on the deck.

Japanese cotton is better than drug store cotton. Kho Gen Do is widely used. If there's a Sally's beauty supply, you can get cellucotton which is rayon.

 

[Caterpiller]

Thanks Dave. I'll try slightly longer wick ends, but from what I'm seeing, the rest of my wick is staying very moist with juice and not drying out at all.

I wouldn't worry about the dark patch except for the poor flavour I'm getting.

I'm using some pharmacy bought cotton that is supposed to be surgical grade, but may not be great quality.

It's a little hard to source better quality here in Malaysia, but I have ordered some KDG from Fasttech, still waiting for it to arrive, been 10 days so far.

If you could post a couple of pictures of your wicking, it might help me out.