Kayfuns and dry hits after refill

[Necrosis]

Apologies, this ended up longer than I wanted. Haven't slept yet and losing my mind.

So this has been a phenomena plaguing me for months now. In short, I get what seem to be random dry hits. I've experimented with so many different microcoil builds in shape, size, and resistances and worked with various lengths, thickness, and density of cotton balls and yarn. Results are... consistently bad, and happen on all my kayfuns.


Each fresh wicking starts the same, with a fresh battery and a freshly filled tank, it vapes just fine. A few configurations crap out and cause problems mid way, but most work as intended. My resistances are typically either 1.2ohms or 1.5ohms depending on what I chose to build.


1) When I refill the tank, for the remainder of that wick's life, it will have intermittent dry hits.
2) Replacing the battery (mech mod) mid vape usually triggers consistent dry hits. If I leave the same battery in for tank #2, I am less likely to have issues. By the end of two tanks, I end up around 3.9v left on the battery.
3) Even if vaping fine on the second tank, if I set the mod down and leave it alone for a length of time (30+ minutes), the next hit is more likely than not a nasty dry burnt hit.


The consistent pattern is everything goes to hell when I refill the tank, or top off the first. I top fill by plugging the air hole with my finger, unscrewing the top, filling it up (not all the way to the top), lightly thread the topcap back on until I get resistance telling me the o-rings are making contact, flip over, wait a few, then screw. I've tried screwing with both my finger on the airhole and off. Depending on circumstances, I may have to flick out the juice that's flooded the chamber and leaked out around the top cap during the screwing in process (note: every disassembly, I open the top part of the chimney to confirm that the wick didn't move and lose contact with the deck, and to date, not once have the wicks moved). I've also tried alternatives like blowing into the air hole upside down, as well as firing while blowing through that air hole upside down, doesn't make a difference.


My original and primary kayfun is all steel, but the russian (all clones) I'm using with the plastic tank, so I've been experimenting with priming techniques using that, thinking that I'm refilling it wrong causing a vaccuum problem that wont get remedied until it's washed and a new wick installed. Primer puffs do produce bubbles flowing up and they do usually show up after every hit. I've also tried changing draw from loose to tight, while results differ, nothing changes in this regard. Also tried priming by blocking the air hole, and loosening the top cap enough to see bubbles then tightening it down.


So I end up asking myself alot of questions, and I have absolutely no clue.
If I'm seeing bubbles every draw, why do I get a dry hit if I leave it alone after that for a length of time? Surely there is juice in the wick and deck from the last draw, where did it go?
If there's a problem with the seal, such as the o-ring on the chimney, why am I not getting flooding? I'll get gurgling from time to time if I'm drawing too hard.
If a full battery worked perfect with a fresh wick and tank, why does it want to burn later on when I change the battery to a fresh 4.2v?
If the wick was moving out of position from turning it upside-down, why does it not remain a consistent problem from that point on? I've even used strategically placed tooth picks in the deck to secure them (don't do this with metal) and still had the same results.


All I can say in the end, it feels like once I refill a tank, any kayfun style tank, I break it's ability to deliver juice correctly. Two of my devices have dremeled out juice channels which didn't really help the problem, though it does seem to improve flavor and performance. Opening the top after giving up on an attempt has always had my wick sitting right in place with the juice channel open (though I've tested with the wick covering the channels as well with virtually identical results).

 

[300fury]

Sorry but I don't see where you mentioned the type of wicking material. I use cotton, what has worked perfectly for me is to roll the cotton and thread through the coil with very little resistance. This leaves the tails equal on both sides so the wicking is consistent with both channels. Now , and this is the crucial part for me, place the chimney over the cotton tails and pull them through. I do not have any liquid on them at this point, what you are left with is bunny ears sticking out the chimney. Cut the cotton down to a quarter inch above the chimney, take a screwdriver and gently push the cotton down , don't pack it down, if you have to do that there is too much cotton. I run 50 50 juice with a micro coil at .9 ohms..... Hope this helps a bit. Good luck

 

[Tibby]

Some thick high VG liquids wick like crap with cotton in a Kayfun.

 

[tw33k]

I use 100% VG in my full-sized Russians and found I had to tighten the air flow and pull a bit harder to avoid the same thing happening. What juice are you using?

 

[Asmo6]

Mine is a 3.1 clone. It uses the needle valve.

I don't have this problem. I don't hold air holes, or prime anything.

On the older kayfuns did you have to take them apart to fill them? I used to do that but I had the opposite problem - where it would flood. Isn't there a fill port on all kayfuns? Like under the bottom or something?

Secondly. Your wick. You put it in the channels?

DON'T!

Just set it on the little shelf above them. I usually do a little half curl and stick it to the side of the deck well above any channel. I also didn't hog out my juice channels and have no issues whatsoever.

I put just the tip of the wick in the channels on the aqua. But never a kayfun. You fill it. The wick in the channel swells where the fresh juice hits it. And boom. It chokes off the flow.

The channels on the KF are so shallow the wick just cannot be in them IMO. If you've modified your gear, then now the problem is yours to fix.


Cotton puffs up over time with saturation and sitting in juice. People also tend to use way more than they need to. (myself included.) I frequently have to clip the end of the wick coming out of the coil to pull it free after vaping 2-3 tanks. It's so plumped up it would rip my coil off the deck if I just pulled it.


Here's a perfect example of how far my wick goes. As illustrated by random internets photo.

I make my coil perfectly perpendicular though and still add that little half curl so the wick lays on that upper deck above the channel. But that's very similar. And it works. Like I've put oh, 180ml through this coil. And it never gets a dry hit.

 

[steel bender]

Wick in the channels = bad. Wick placed on top of the channels = better than pushed against the side of the block imo.

No vacuum is created during the fill process as air can always escape through the channels if bottom filling. Top filling is a little trickier, but basically the same thing, after catching the threads and inverting, when you screw on the top cap the rest of the way, air has to get out somewhere, either through the threads or the channels, because it's now inverted with the bubble at the channels.

Really, the only issue you should have from top filling is leaking, not dry hits.

With a fresh wick/coil, your wick is already saturated with juice, so it starts out vaping nice. Then while vaping, the negative pressure vacuum thing gets started, keeping your wick wet.

Just because you see a bubble or two doesn't necessarily mean you won't get a dry hit. If the wick is dry you might need to see several, before it gets saturated again.

After refilling if the tank is full, it's harder to get that vacuum started again, so some primer puffs may be needed. Especially with a fresh battery giving you your highest 4.2 voltage (assuming this is on a mech?). Try filling the tank only half way once and see if that helps you.

After leaving the tank alone for a while, you may need to get that vacuum started all over again.

I get occasional dry hits every morning with a newly full tank and a fresh battery. I just put my thumb over the air hole and take a primer every few pulls. After going through a little juice and draining the battery a bit, I'm usually good for the rest of the day.

 

[ConConCon]

Wick in the channels = bad. Wick placed on top of the channels = better than pushed against the side of the block imo.

No vacuum is created during the fill process as air can always escape through the channels if bottom filling. Top filling is a little trickier, but basically the same thing, after catching the threads and inverting, when you screw on the top cap the rest of the way, air has to get out somewhere, either through the threads or the channels, because it's now inverted with the bubble at the channels.

Really, the only issue you should have from top filling is leaking, not dry hits.

With a fresh wick/coil, your wick is already saturated with juice, so it starts out vaping nice. Then while vaping, the negative pressure vacuum thing gets started, keeping your wick wet.

Just because you see a bubble or two doesn't necessarily mean you won't get a dry hit. If the wick is dry you might need to see several, before it gets saturated again.

After refilling if the tank is full, it's harder to get that vacuum started again, so some primer puffs may be needed. Especially with a fresh battery giving you your highest 4.2 voltage (assuming this is on a mech?). Try filling the tank only half way once and see if that helps you.

After leaving the tank alone for a while, you may need to get that vacuum started all over again.

I get occasional dry hits every morning with a newly full tank and a fresh battery. I just put my thumb over the air hole and take a primer every few pulls. After going through a little juice and draining the battery a bit, I'm usually good for the rest of the day.

Very good info and i could not have said it better myself!

Sent from my LG-LS970 using Tapatalk

 

[magicmyst]

I used to have problems with flavor drop and dry/burnt hits after every refill (top or bottom) on my KFL+ and R91 until I switched to a different gauge and wrap for my micro coils. Don't know why, but I haven't had any problems since. Here's the thread.

What type of coil and wick are you building?

 

[vapdivrr]

Mine is a 3.1 clone. It uses the needle valve.

I don't have this problem. I don't hold air holes, or prime anything.

On the older kayfuns did you have to take them apart to fill them? I used to do that but I had the opposite problem - where it would flood. Isn't there a fill port on all kayfuns? Like under the bottom or something?

Secondly. Your wick. You put it in the channels?

DON'T!

Just set it on the little shelf above them. I usually do a little half curl and stick it to the side of the deck well above any channel. I also didn't hog out my juice channels and have no issues whatsoever.

I put just the tip of the wick in the channels on the aqua. But never a kayfun. You fill it. The wick in the channel swells where the fresh juice hits it. And boom. It chokes off the flow.

The channels on the KF are so shallow the wick just cannot be in them IMO. If you've modified your gear, then now the problem is yours to fix.


Cotton puffs up over time with saturation and sitting in juice. People also tend to use way more than they need to. (myself included.) I frequently have to clip the end of the wick coming out of the coil to pull it free after vaping 2-3 tanks. It's so plumped up it would rip my coil off the deck if I just pulled it.


Here's a perfect example of how far my wick goes. As illustrated by random internets photo.

I make my coil perfectly perpendicular though and still add that little half curl so the wick lays on that upper deck above the channel. But that's very similar. And it works. Like I've put oh, 180ml through this coil. And it never gets a dry hit.

hey there is my coil again.

 

[lewmaster]

I had a lot of problems with intermittent dry hits on Kayfuns and what totally cured it for me was switching from 28 to 30 gauge kanthal (for kayfuns only). I can run the same ohms as I was with 28 or lower, and at higher wattage if I want to, and I have never had a dry hit since switching.

 

[Jordner]

Wick in the channels = bad. Wick placed on top of the channels = better than pushed against the side of the block imo.

No vacuum is created during the fill process as air can always escape through the channels if bottom filling. Top filling is a little trickier, but basically the same thing, after catching the threads and inverting, when you screw on the top cap the rest of the way, air has to get out somewhere, either through the threads or the channels, because it's now inverted with the bubble at the channels.

Really, the only issue you should have from top filling is leaking, not dry hits.

With a fresh wick/coil, your wick is already saturated with juice, so it starts out vaping nice. Then while vaping, the negative pressure vacuum thing gets started, keeping your wick wet.

Just because you see a bubble or two doesn't necessarily mean you won't get a dry hit. If the wick is dry you might need to see several, before it gets saturated again.

After refilling if the tank is full, it's harder to get that vacuum started again, so some primer puffs may be needed. Especially with a fresh battery giving you your highest 4.2 voltage (assuming this is on a mech?). Try filling the tank only half way once and see if that helps you.

After leaving the tank alone for a while, you may need to get that vacuum started all over again.

I get occasional dry hits every morning with a newly full tank and a fresh battery. I just put my thumb over the air hole and take a primer every few pulls. After going through a little juice and draining the battery a bit, I'm usually good for the rest of the day.

Couldn't have said it better myself!

 

[Arnold Ziffle]

I've had good luck with a small amount of cotton placed over the coil and just touching the deck on both sides. I have it touching the wick that goes through the coil.