Where's the residue coming from in my Kayfun?

[IcyNanners]

I noticed whenever i clean my kayfun there's a lot of black residue built up through the top part of the chimney and the drip tip. So i got curious today cleaned everything, and made a makeshift filter out of a tissue. Fit it down in the drip tip well and vaped for a few hours. I took out the tissue and to my surprise it was very dark brown. Tried the same test with my iClear 30b, and a regular ce5 clearo. Both of those came out completely clear. A few Google searches later and I could'nt find much on it outside of things like "Does vaping stain walls/teeth?"

So my question is, Where is the residue coming from in the kayfun? My only thought so far is the cotton.

My setup:
Kayfun lite, 28g Kanthal and organic cotton. 1.3Ω coil vaping at 12 watts. - Gave Residue
iClear 30b, 1.5Ω Coil head with a silica wick, vaped at 9 watts. - No Residue
ce5 Clearo, 2.5Ω with a silica wick, vaped at 9 watts. - No Residue

Thanks in advance.

 

[Bigflyrodder]

Do you get that residue with all of your ejuices or just the one? I would first try a different ejuice and see if maybe it is a flavor/color issue, if not you may be over-wicking your Kafun which is causing the wick to burn. First I've heard of an issue like this.

 

[Ca Ike]

I have similar issues on my tanks using a spiced cider juice with cinnamon and nutmeg flavors. Reminds me of burnt sauce on a frying pan type ash residue.

 

[IcyNanners]

I've only tried 3 different juices in all 3 tanks through these little tests. I used a clear 0mg Candied Apple 25pg/75vg, a dark amber 18mg Cinnabon 25pg/75vg, and an 18mg 100% vg Peanut butter cookie that was a lighter amber than the Cinnabon liquid. They all gave the same results.

Edit: I did notice that the 0mg juice left a bit lighter residue on the tissue, but that was about it. Also the over-wicking could be a factor, but I tend to completely burn through the wick and taste that burned cotton when that happens.

 

[Completely Average]

When you first got the Kayfun did you clean it thoroughly inside and out with alcohol to remove the machine oil from the manufacturing process?

 

[IcyNanners]

Yeah, Warm soapy water followed by an unflavored vodka bath and another rinse.