Wicking problems... I think.

[Bill Linton]

Hi folks, haven't looked in for a while and, as usual, it's when I've got a problem!

I've suddenly come up with an issue of getting dry hits, and can't for the life of me understand why.

My last visit to ECF concerned my dissatisfaction with the tank I was using and asking advice on which tank to buy... which majority advice prompted me to purchase a Kayfun Lite Plus (5 Pawns), which I've had great service from for the past year... up until about a week ago.

I'm burning a 1.6 Ohm, 28 gauge Kanthal coil @ 9 watts, and wicking with Japanese cotton. I've cleaned the tank and deck, replaced the wick numerous times, re-coiled three times, and am doing nothing I wasn't doing before.

Looking forward to any advice, which will be gratefully accepted.

Cheers.

 

[Imfallen_Angel]

Could there be a bad contact with your mod (or something else going on with your mod) and it's pushing out more than the 9W?

 

[Bill Linton]

Hi Imfallen-Angel, and thanks for your response. I'm not getting any indication of my mod putting out excess power, as the coil Ohm, Voltage and Wattage readings are all normal. I'm no electronics whizz, so that's the limit of my expertise.

One thing I haven't checked is the contact points on mod or tank, and will see if the mod end will prise up, as that is something I've had probs with on other mods.

Thanks again for your help.

Cheers.

 

[Imfallen_Angel]

Hi Imfallen-Angel, and thanks for your response. I'm not getting any indication of my mod putting out excess power, as the coil Ohm, Voltage and Wattage readings are all normal. I'm no electronics whizz, so that's the limit of my expertise.

One thing I haven't checked is the contact points on mod or tank, and will see if the mod end will prise up, as that is something I've had probs with on other mods.

Thanks again for your help.

Cheers.

No problem, question is, after a year you should know how to do this build with your eyes closed.. so I wouldn't believe that you're doing anything wrong/different, so I'd look for something technical.

Have you tried the tank with another mod, another tank with that mod and see what's happening?

I don't have that tank so I can't say more than some general things, such as: have you tried putting only the deck, priming your wick and firing your mod to see if everything looks ok as you'd be able to see the coil and the vaporizing.

For your cotton, new batch? Pads? (and if pads, you aren't cutting your piece across the grain - direction of the fibers which are usually aligned with the wide of the pad). Cutting across the grain instead of with it will make a HUGE difference (and a bad one).

Are you using the Scottish roll approach with the cotton pad?

Just trying to come up with anything that might help here and probably stuff that you already know or tried, but just in case.

 

[dyanaprajna]

There's only two things I can think of that would be wrong: wicking, and too much heat too quick. But it sounds like you have the wicking down, so the only other thing I could think of is the coil is getting too hot too fast. Imfallen has given some good ideas to try and troubleshoot the issue.

 

[englishmick]

Could it be an air lock / vapour lock? Don't know much about them, something to do with an air bubble getting in the pathway the juice takes from the tank to the wick. It stops juice getting to the wick which would give dry hits. I've had that problem with other tanks but not a KFL. I think you can tell if that's the problem by loosening the top of the tank a little and watching for bubbles coming up.

 

[englishmick]

Got a question. Do the dry hits start right away or can you vape on a tank for a while before the problem starts?

 

[dyanaprajna]

Yeah, chain vaping will cause that too. I have a request for you: could you possibly post a picture of your build? It might help isolate what's going on.

 

[Bill Linton]

Thanks for the replies, guys. You've given me a thing or two to thnk about, so I'll mill over your suggestions and get back to you tomorrow.

Cheers.

 

[VHRB2014]

Make sure it holds vacuum. With the RTA completely assembled, but out of juice, block the bottom two air holes with your fingers, then apply a vacuum to the mouth piece and make sure it stays holding the vacuum. A tiny little leak could be affecting its ability to wick (pull up) juice. After working fine for a while and with this being all of the sudden, I`m thinking maybe a o-ring has had enough and needs to be replaced.

 

[Bill Linton]

Hi folks, as a response to your suggestions/querries...
Looking back to the start of my issues, it didn't begin with dry hits/dry burns, but I do remember a leak from the airflow adjuster screw some weeks ago, which I cured by taking the tiniest strand of thread-tape to wrap the threads. I then had the airflow screw gouging the top of my mod, so tightened it a half turn. In addition to all of the above, I've been noticing a reduction in flavour quality over the past few weeks.

To the present, I prised up the contact on my mod, changed mods, which made little or no difference. I tried pulling a vacuum in the empty tank, to no negative result.

Considering airlock or questions of pressure differential, blowing juice through the breather and sucking it back[a filthy habit called reverse-circulation in the oilfield], or burning off the flooding should revert to original position... no go! Capillary action probs caused by cotton cut across the grain; checked the pad I've been cutting from and all seemed good, but chucked it anyway.

The dry hits have been starting after about 1 ml of juice has been burned from a re-fill... hmmm?

Cut to the chase; the analyst in me wanted to try out each suggestion to discover the cause, but the drug addict just wanted his b*ng back. I checked out YouTube "Kayfun troubleshooting" and came up with a chap named aplus562, who has posted a very detailed deconstruction/reconstruction of the Kayfun Lite Plus in 5 episodes, with some very good pointers with regard to inherent, but fairly easily resolved problems with the mod... well done that man, and I recommend his videos.

I took the whole thing apart, cleaned, changed all o-rings, replaced acryllic cylinder, re-coiled, re-wicked and rebuilt it in about an hour. There was some gunk inside the central pin/positive post [which doubles up as airflow duct] and a little deep in the air intake. The main point is that the result seems to be great so far, although I've been doing more typing than puffing... have you tried typing with your fingers crossed?

So far so good. I've got my flavour back, my tank's working like a pithead train and I'm confident I'll still be happy when it's time to refill it.

Thanks a lot for the help you've given guys, as they say, five heads are better than one, and I doubt I would have resolved to change as much as I have without the food for thought your questions have given.

Can't thank you enough,

Billy.

 

[englishmick]

Hi folks, as a response to your suggestions/querries...
Looking back to the start of my issues, it didn't begin with dry hits/dry burns, but I do remember a leak from the airflow adjuster screw some weeks ago, which I cured by taking the tiniest strand of thread-tape to wrap the threads. I then had the airflow screw gouging the top of my mod, so tightened it a half turn. In addition to all of the above, I've been noticing a reduction in flavour quality over the past few weeks.

To the present, I prised up the contact on my mod, changed mods, which made little or no difference. I tried pulling a vacuum in the empty tank, to no negative result.

Considering airlock or questions of pressure differential, blowing juice through the breather and sucking it back[a filthy habit called reverse-circulation in the oilfield], or burning off the flooding should revert to original position... no go! Capillary action probs caused by cotton cut across the grain; checked the pad I've been cutting from and all seemed good, but chucked it anyway.

The dry hits have been starting after about 1 ml of juice has been burned from a re-fill... hmmm?

Cut to the chase; the analyst in me wanted to try out each suggestion to discover the cause, but the drug addict just wanted his b*ng back. I checked out YouTube "Kayfun troubleshooting" and came up with a chap named aplus562, who has posted a very detailed deconstruction/reconstruction of the Kayfun Lite Plus in 5 episodes, with some very good pointers with regard to inherent, but fairly easily resolved problems with the mod... well done that man, and I recommend his videos.

I took the whole thing apart, cleaned, changed all o-rings, replaced acryllic cylinder, re-coiled, re-wicked and rebuilt it in about an hour. There was some gunk inside the central pin/positive post [which doubles up as airflow duct] and a little deep in the air intake. The main point is that the result seems to be great so far, although I've been doing more typing than puffing... have you tried typing with your fingers crossed?

So far so good. I've got my flavour back, my tank's working like a pithead train and I'm confident I'll still be happy when it's time to refill it.

Thanks a lot for the help you've given guys, as they say, five heads are better than one, and I doubt I would have resolved to change as much as I have without the food for thought your questions have given.

Can't thank you enough,

Billy.

Do keep us updated on whether it lasts. I'm going to check out that Youtube link. I've never completely disassembled a Kayfun except for cleaning out a new one before using, maybe it's a good thing to do periodically. And the analysis of design features sounds intriguing.

cheers

 

[DaveP]

Bill Linton wrote:
So far so good. I've got my flavour back, my tank's working like a pithead train and I'm confident I'll still be happy when it's time to refill it.

Wicking is the #1 cause of dry hits if airflow is good. Glad you solved the problem.

Most of the time when I have dry hits the wick has lifted off the coil deck for some reason. It's hard to troubleshoot because you can't see that well looking down into the deck once the small chimney section is removed. If you remove the large section of chimney that usually disturbs the wick and it moves with the twisting motion of unscrewing the chimney.

I install the chimney bottom section on the deck once I wick and make an attempt to ensure that the wick didn't move at that point. I poke it down and move it slightly away from the juice holes to ensure that wicking doesn't block juice entry to the coil deck. That's about all you can do. If it works vape it! If not take it apart and try again ...

You didn't mention whether you were using a slanted coil or a coil centered equally between the posts.

 

[Bill Linton]

Do keep us updated on whether it lasts. I'm going to check out that Youtube link. I've never completely disassembled a Kayfun except for cleaning out a new one before using, maybe it's a good thing to do periodically. And the analysis of design features sounds intriguing.

cheers

One very good tip was not to over-tighten the centre post if your model does not have the sump/collection-chamber at the foot of the tank [Kayfun 5 Pawns], but is a solid, machined piece from base to deck mount, as the thread on the hollow post can be too easily stripped.

Cheers.

 

[Bill Linton]

Wicking is the #1 cause of dry hits if airflow is good. Glad you solved the problem.
You didn't mention whether you were using a slanted coil or a coil centered equally between the posts.

I can't believe I just did that, spent 10 minutes writing a response, then wandered away to make a brew and forgot what I'd been doing... and lost the lot! I'm hoping it isn't dementia!

I'm fairly convinced wicking wasn't the problem, DaveP. I'd re-wicked so many times, changing amount, length of cotton etc, so many times I was tired of doing it. Curiously, I'd began fixating on the possibility of wicking material being tampted into the juice intake. But you're right... that little niggling doubt that you can't actually see what's going on can get into your head... a bit like our Intelligence Services... but we won't go there!

My coils tend to lie at a slight angle to reduce leg length and, presumably, save power and lengthen battery life.

Anyway, that problem is now resolved, so... onward McDuff.

Something that hadn't occurred to me until now is that I have a dozen retired tanks lying about the house, but not one I'd call a favourite spare. Am tempted to purchase another Kayfun... unless someone has a suggestion for a credible alternative.

Thanks again for all the helpful advice folks.

Billy.