Made a discovery that seems good enough to share. For those of you that managed to get one of the 26650 tobeco kayfuns, I just found a way to run it in short mode with no extra parts needed. I shall dub it the “Kayfoid” build in honor of both the kayfun and the spheroid – it is a bit of both! The only extra supply you’ll need is some fluff. GP sells it through vapourart and domo vapor.
You’ll only be using the top cap, one of the stainless tank sections and the base (set aside the clear tank, one of the stainless tank sections, and the chimney/cap). Build a microcoil as normal, but I would beware using anything much wider than a 5-64thdrill bit. My coil is running at 1 ohm and works great for this application. Once your coil is installed in the base as usual, wick it with cotton, but instead of just touching the bottom of the “deck”, leave enough to go all the way to the outside of the whole base, proper. Wet the cotton with juice and sculpt it in to follow the juice channels down from the deck, and continue to follow them on the floor of the base, staying just barely clear of the threads where the tank section will screw down.
Now add the stainless steel tank portion. This is where it becomes spheroid-esque. Cut a piece of fluff about 4.5 inches long and about ¾ to 1 inch wide. Hold it as if to make a V shape along the length (essentially, folding it in half lengthways as you go). Tuck it in between the wall of the tank and the build deck, working to lightly pack it in place as you work your way clockwise around the circle between the deck and tank wall. With this length, you should be able to make about 2 complete wraps around the build deck. At first it will be kind of all over the place, but do your best to pack it in evenly such that it exactly fills the available space.
Next, wet it with about 2 mils of juice from the top. The juice will help the fluff to hold its position. This next part is key… Shape the fluff so that it remains entirely clear of the coil and the immediate space around it. Fluff is not meant to be in direct contact with your coil. Once you are happy with the shape of the fluff (essentially, you are sculpting an area that will act like your evaporation chamber directly around the coil) go ahead and finish filling with juice to full saturation. I got just shy of 5 mils in mine. (!!)
Almost done. Remove the o-ring from your kayfun topcap—not needed in this build. This will otherwise be sitting *right* over the coil and we don’t want it to melt. Once that is done, carefully screw down the topcap. Use daylight or a penlight to peer down the hole for the topcap and make sure the fluff stayed clear of the coil. If any strayed, use a small screwdriver or syringe to coax it away.
Last step: CHECK YOUR OHMS. This build results in the top cap sitting extremely close to the coil, so the possibility of shorting to the top cap exists.
And so why would you want to do all this?
~ The resulting atomizer is about ½ as tall as a standard (18650) kayfun, but still holds more juice, almost 5 mils. What it lacks in length it makes up in girth. And yes, that’s what she said.
~ Flavor, imho, is perhaps a tad better than a standard build. I believe this may be because as you draw, the vapor is whirling around in the juice coated fluff, and essentially getting an extra shot of flavor along the way.
~ Vapor production is also a tad better than a standard build and *noticeably* warmer. This makes sense because the coil is essentially right under the drip tip – no chimney between you and it. I’m getting flavor and vapor pretty much on par with an RDA, though the airflow on this clone isn’t enough to allow for real lung hits of course.
~ No issues with gurgling, leaking or dry hits at all. Chain vape it dry – perfect hits every time – and you can set the airflow however you like it without worrying about the vacuum effect upon which the kayfun otherwise depends. What you basically have here is an RDA with airflow coming from under the coil, and a “juice well” that holds 5ml.
~ Filling is a snap – no more screwdrivers to worry about. Simply remove the drip tip and use a syringe to add liquid at an angle (remember the airflow is directly under the coil, so avoid that hole as you fill – placing a finger over the air port at the bottom will also keep things from getting too messy when you refill). You might need to blow through the air port just once after a fill to clear it – that’s it.
The only downside I can find to this build is that when it comes time to rewick the cotton, you are forced to remove the fluff (which also tends to stick to the topcap as you open it). But for all the other advantages, this seems like a price worth paying. And by all means, please do experiment with this. Could be that the cotton wick does not need to rest all the way down under the fluff. Or hell, could be you could use cotton in place of the fluff entirely. Could it work with dual coils? Probably. So play with this and see what you can come up with to make it better still!
In the end, the real reason to do this, as I see it, is to make a 26XXX mod as short as possible. I dream of a pocket friendly 26XXX mod that I can vape all day without dripping, and this is getting me half way home!
Next time I rewick, I’ll take pictures of the process. But wanted to get this discovery out there!