SXmini M Class + Subtank Mini RBA = all over the map

[dam718]

One of my first nickel builds was in the RBA section of my Subtank Mini.

And that first build was great!

Since then I have also done Ni200 builds in:

Kayfun Lite+
Dark Horse
Marquis

All of which have also been great.

I would always go back to the Subtank Mini though, as that's what I carry around with me most of the day. A few days ago I switched out the coil and wick cause I was changing flavors. Now, I can't get this RBA section to stabilize for the life of me.

I have put at least 4 different coils in here all spaced, all between .10 to .16. All of them using 30AWG Ni200 (That's all I have right now, have some 26 and 28 on the way). All wrapped on a 3mm post. No visible shorts in the wire...

The juice I'm using is a 50/50 VG/PG juice

What I'm observing is that if I run it at low joules (Less than 15), the temp well get to where it's supposed to be, and just hover there, which is what I expect it to do. But say I go up to like 18J, it will fire normal for a couple of seconds and then immediately hit the temp limiter, no matter how high I set the temp limiter.

For example, those first few seconds could be vaping at 418F or somewhere around there, and then it will IMMEDIATELY jump from 418 to 550 and start popping the limiter. I run it back to 12J or so and it goes back to normal.

This is only on the Subtank RBA. The KFL, and my drippers all work fine. So I don't think it's an SXmini M Class issue, or a coil making issue.

I tried modifying the base of the RBA where the 510 positive pin was making better contact with the RBA section, but that didn't seem to help.

Has anyone else seen this type of behavior, and what did you do to correct it?

Really would like to get this working again! (Or I guess I could just get a Lemo 2 and throw this thing in the dumpster? LoL)

 

[Pete54]

It sounds like a hot spot on the coil. I'm not a big fan of the Kanger Sub-Tank, in fact mine ended up in the garbage!
One thing I do, to detect a hot spot prior to wicking, is turn off temp mode and turn down the joules to 6.0 - 6.5. I fire the coil in dim lighting until I start to see a faint glow. If the glow is in the middle of the coil, I'm good. Sometimes you'll see one of the legs start glowing. That will be a problem!

 

[dam718]

I never dry burn my nickel coils... I know I have sure seen plenty of people doing it, and it would explain a lot of there's a short in there somewhere...

I don't see anything that's touching, but I'll try this next time...

I did just pull apart the .5 Ohm OCC coil it came with and rebuild it with Ni200... Coil came out to .188 (Was going for .15, oh well) and it's working brilliantly.

It's just this stupid RBA head that is acting all crazy

 

[TheotherSteveS]

I have had the opposite experience.. Rba is fantastic on mini but the kanger ni occ heads are inconsistent at best. Haven't tried a rebuild yet...

 

[dam718]

Spoke too soon... The rebuilt Ni200 OCC head is crazy too...

I'll try dry burning the coil in the RBA before wicking it and see how it fares...

Gonna try twisting the 30AWG Ni200 with some 32AWG Kanthal on the RBA, and doing a touching coil. At this point, it can't get WORSE, know what I mean... LoL I'll try anything

 

[dam718]

So far so good with the 30AWG Ni200 + 32AWG Kanthal twisted build. Resistance is a bit high, running at .2 with 6 wraps 3mm I.D.

The temps are a bit off, as can be expected, having to run about 30-50 degrees cooler than I would have expected to for this juice. But it's stabilizing at around 315, set the temp limit to 330, and it's not hitting the temp limit at all. Nice and smooth, like it was before...

No clue what was going on with the straight nickel build. Maybe I did have hot spots? I dry fired this one before wicking, and there were no hot spots. I was going to try touching coils, but I decided to go with spaced coils just to be on the safe side. Nice burn from the inside out on the coils, with all coils burning even after a couple of seconds. Looking good, no hot legs etc...

What I will say about this setup compared to the straight nickel... The flavor is a lot better, IMO. I'm vaping a juice called Plantains de Flambé from a company called "The Vial" here in Hawaii. It's a Banana's Foster style juice and it was GOOD on the Ni200 build... On this Ni200/Kanthal build it is REALLY GOOD. Rich, complex, just delicious... Whatever it was missing with the nickel build, it's back, and it's nice!

 

[inspects]

Really would like to get this working again! (Or I guess I could just get a Lemo 2 and throw this thing in the dumpster? LoL)

I think you'll be much happier......

 

[dam718]

I think you'll be much happier......

How so? Tossing the STM for a Lemo 2? LoL, I think you're right...

That Goliath looks pretty good too, but everyone seems to be raving about the Lemo. I have to try it just because...

 

[jackmormon]

I am about ready to toss my Lemo 2. Washed it, did my normal NI200 build 3mm, 8 wraps. Worked flawlessly for five tanks. Put it through the ultrasonic cleaner and cannot get a stable resistance for the life of me. 4 new builds. Constant new coil messages and really high resistance or jumping resistance on a DNA40, way too low resistance readings and poor performance on an SX Mini M. The DNA40 sure tells you when you have a problem, the SX makes it appear to be stable but the poor performance is obvious. I really wanted this tank to work with NI200. Will keep messing with it. Obviously 510 issues.

Now onto the subject of this thread.... The Subtank Mini with the RBA head is the ONLY, and I mean ONLY tank (out about 15 I have tried) that is always 100% rock solid with NI200 other than an Erlprinz which I no likey due to airflow. Both mySubtanks never have any issues after the podunk-steam-rubber-band trick to make sure the 510 is seated by using a piece of rubber band to wiggle the 510 pin to make sure it is seated solid against the base.

With the same trick worked with the Lemo 2. Arghhhhhhhhhhhhhhhhhhhh!

 

[dam718]

Both mySubtanks never have any issues after the podunk-steam-rubber-band trick to make sure the 510 is seated by using a piece of rubber band to wiggle the 510 pin to make sure it is seated solid against the base.

Not good news about the Lemo 2. The only tank I have have GREAT success with is my Kayfun Lite+, but the airflow on that poor tank, as solid as the performance of the coil is, is just too restrictive.

What is this rubber band trick you speak of?

What I had to do with my Subtank was take out the insulator that holds the floating positive pin into the airflow controller section, and cut down the flange a bit so the pin will push up into the 510 connection a bit. When I screw in the RBA section, it now pushes the pin out just a bit, so it seems like a solid connection. Is the rubber band trick a better solution?

Even this coil I am using now has started to go crazy. I've just had to set the temp lower and let it bounce off the temp limit. I don't have to do that with my Kayfun or my drippers... But I don't want to bring a dripper to work, that's a PITA

 

[jackmormon]

The rubber band trick is just using a piece of fat rubber band and holding it against the bottom of the 510 pin (on the outside.) I just rotate clockwise, counter clockwise and rock back and forth. Seems to seat it perfectly. My theory is that residual physical resistance in the insulator is what causes irregular contact. The "seating" of the 510 with the rubber band seems to take care of it for me. I think it "works" out any physical resistance in the insulator that would cause the pin to move.

Atomizer stability is so crucial for TC builds and it is the thing I struggle with the most. Podunk Steam (a member & modder here) inspired the "rubber band trick" when he suggested I wedge a piece of rubber band inside of a lemo 1 between the center post and the bottom dome, assemble and the rubber band kept the bottom dome from spinning when tightening the 510. Big help with the lemo 1, but still not as stable as a Subtank Mini for me.

With the lemo 2, I tried Podunk's trick of flipping the 510 so that wide part is inside but I get no atomizer readings with this. Even tried flipping the insulator the other direction. Still no luck. I REALLY want the Lemo 2 to work with TC. I just bugs me to no end that the atomizer worked beautifully until meeting an ultrasonic cleaner.

 

[dam718]

What would work really nice for the Subtank is just have the positive connector of the RBA section actually BE the positive post that sticks out of the 510... I think the spring loaded 510 of the SXmini pushed hard enough against it that it should be solid, but it just doesn't work like my other atomizers do. It's depressing cause I WANT to find a solution that's solid. Without having to buy 14 tanks to find one that works.

I'm starting to think there is something wrong with my Subtank Mini? But how could that be? LoL It's a pretty simple device.

 

[dam718]

I think I may be running too little wicking material, and that's why the temps are shooting up, because there are portions of the coil that are indeed dry and are getting hot, thus raising the resistance. I think the first time I did a build on the Subtank RBA I used what I thought was way too much wicking material. Now that I have used much less, I seem to be having issues with the resistance holding steady.

Will report.

To the admins, if this is in the wrong place, feel free to move it. I know the Temp Control section is under APV's, but I thought this was related close enough that it belonged here as well. Unless we can make a subsection for Temp Control Coils? That would actually be quite helpful

 

[dam718]

Finally got tired of the crazy stuff this RBA head was doing, so I pulled off the tank and chimney section to see what was going on. Sure enough, I had a hot leg, but only on the negative post. Pulled the wick and fired it in power mode and it was fine, burning from the inside out with no hot legs. Put a wick back in and tried the water test, and bam hot leg on the negative post again. what the heck...

I found some odd things going on when I took some test measurements on the RBA of the subtank installed on the airflow base...

First, I checked continuity between the positive pin to the positive post on the build deck. That was all good. Checked negative as well, also good.

Then I started doing some resistance checks. Between the positive and the negative post I was showing around 1 Meg Ohm of resistance... Well that didn't seem right... I would think the insulators should completely isolate the positive from the negative, and I should show no resistance between the posts. So I started taking everything apart... Pulled out positive post from the airflow base and pulled the insulator. I pulled one of the stick OCC insulators from the bottom and jammed it in the 510 connector, it's a bit tight, but it's now showing no resistance between ground and the center pin... Strange. The RBA section was still showing some resistance between the positive and center pin, so I pulled it apart and washed everything out real good and dried it out. Put everything back together and rechecked my measurements across the posts of the build deck. No more resistance.

So I popped on a twisted 30AWG Ni200 5/6 wrap 3mm I.D. coil that measured out at .07 Ohms... And now all is happy in vapeland... Not sure if residual juice was causing the resistance reading, or what... Anyway, it would seem the build I have in there now is performing well, so I'll leave it alone til the Lemo 2 arrives. I went ahead and ordered one, as even if it is wonky with a nickel build, it should still be pretty amazing with a Kanthal build. We shall see!

 

[jchisholm]

Unscrew the RBA from the deck, put a small allen key or the like through the airhole at the bottom of the RBA and tighten that sucker up. Mine was doing the same thing and it hasn't fluctuated since.

One of my first nickel builds was in the RBA section of my Subtank Mini.

And that first build was great!

Since then I have also done Ni200 builds in:

Kayfun Lite+
Dark Horse
Marquis

All of which have also been great.

I would always go back to the Subtank Mini though, as that's what I carry around with me most of the day. A few days ago I switched out the coil and wick cause I was changing flavors. Now, I can't get this RBA section to stabilize for the life of me.

I have put at least 4 different coils in here all spaced, all between .10 to .16. All of them using 30AWG Ni200 (That's all I have right now, have some 26 and 28 on the way). All wrapped on a 3mm post. No visible shorts in the wire...

The juice I'm using is a 50/50 VG/PG juice

What I'm observing is that if I run it at low joules (Less than 15), the temp well get to where it's supposed to be, and just hover there, which is what I expect it to do. But say I go up to like 18J, it will fire normal for a couple of seconds and then immediately hit the temp limiter, no matter how high I set the temp limiter.

For example, those first few seconds could be vaping at 418F or somewhere around there, and then it will IMMEDIATELY jump from 418 to 550 and start popping the limiter. I run it back to 12J or so and it goes back to normal.

This is only on the Subtank RBA. The KFL, and my drippers all work fine. So I don't think it's an SXmini M Class issue, or a coil making issue.

I tried modifying the base of the RBA where the 510 positive pin was making better contact with the RBA section, but that didn't seem to help.

Has anyone else seen this type of behavior, and what did you do to correct it?

Really would like to get this working again! (Or I guess I could just get a Lemo 2 and throw this thing in the dumpster? LoL)

 

[mesamay2003]

Personally, I am finding TC to be somewhat of a pain in the .......I really don't want a new hobby, I just want a simple, great and consistent vape. Some of you guys must be spending LOTS of time trying to perfect your nickel builds I like the concept, but...

 

[dr g]

Personally, I am finding TC to be somewhat of a pain in the ****...I really don't want a new hobby, I just want a simple, great and consistent vape. Some of you guys must be spending LOTS of time trying to perfect your nickel builds I like the concept, but...

prebuilt coils eliminate the time commitment.

 

[mesamay2003]

I have and use then Ni200 OCC coils when I am not in the mood to deal with building...and I have not been that impressed...not sure it is the coils I have a problem with, but more how TC is achieved...it seems I am spending much of the time when taking a pull, vaping at about 6-8 watts when you look at what's actually going on...this would explain the somewhat lackluster experience :-(

 

[dr g]

I have and use then Ni200 OCC coils when I am not in the mood to deal with building...and I have not been that impressed...not sure it is the coils I have a problem with, but more how TC is achieved...it seems I am spending much of the time when taking a pull, vaping at about 6-8 watts when you look at what's actually going on...this would explain the somewhat lackluster experience :-(

That is the correct function. It only supplies the proper amount of power to maintain the set temperature. Raise the set temperature if you want more.

 

[mesamay2003]

Therein lies the rub, I think we are going to find out real soon that the previous vape experience many people enjoyed using traditional kanthal (and I'm not talking extreme wattage or builds) are running quite a bit higher temps than the recommended TC range. I know I can tell a big difference running a Ni200 occ coil at 420-450 degrees and 25-30 watts, and a regular .5 ohm occ at 20-22 watts...not even close. It will be interesting when some info comes out on the temp/liquid studies...