Temp control on Crown SS coils

[Powerman]

So I just sold my SX Mini, but I had the firmware upgrade for user TCR. I have two DNA 200 boxes. VS and VT200. I've used the 0.25 and 0.50 Crown SS coils on both. TC works fine on both. Despite everything from Uwell saying the coils are 316, everyone uses 304 TCR. The difference is around 50F at 400F. Everyone, including me, say the 316 TCR is too cold. I did some burn tests on a dry coil, and the results were a little inconclusive. But using 304 TCR of 1016, it would smoke at 475F.

Any hoo... I had one coil I thought was burning but wasn't sure. But then there was no doubt. On the SX mini and DNA. Oh well, bad coil.

Lately, on both DNAs the TC has been inconsistent. Maybe 10% of the time sort of. TC works fine. Period. Then, another time I'll go to vapers, and it's cold. I like around 450F. But it feels like nothing. And no initial punch either.

Then, a couple times now, I go to vapers, and it's super hot. Like full power. I have power at 100w. It doesn't let up. It doesn't temp control. Yesterday, when it happened, I lowered temp all the way to 200F but no change.

I let it sit for a while, and it works fine again. Today, it was much hotter than normal. But turning temp down it did work, but at like 350F. I never use power mode. Never lock my ohms. Never connect a hot atty. Ohms are not fluctuating all over. But both boxes have done it. So I can only assume it's the Crown.

The VT200 seems to hit noticeably less than the VS. Even though the settings are identical. And swapping tanks it's the same. Like the VT200 is set 50F lower. But, settings are identical and I use the same curve.

It's just really weird. I am lost as to why it all works normal, even compared to the SX Mini, but then every now and then it doesn't. It's happened 5-6 times now. Anyone have any ideas?

 

[cascadian]

Anyone have any ideas?

Didn't you post yesterday in another thread that the Crown's coils were confirmed to be SS welded to nickel legs? If that is indeed true the Crown is not suitable to be used with TC using the factory coils. Not only will it not work well as I have experienced, it can't work well.

 

[Powerman]

I've looked for confirmation, but can find any. On Evolves early adopter forum, a user posted Evolve confirmed it. But it's just a post on the Web with no evidence. I posted there but got no reply. Other people say it is all one material.

So what you are talking about, if it has nickle legs... It it obvious? Like one metal stuck to another obvious? I have a couple coils I'm going to take apart.

And I get what you are saying... But if it was a quality joint, one metal to the other, would that be so bad? Seems the SS section would still be the part being controlled. I don't know though.

And if it was so terrible, it seems like it would just be inconsistent all the time. What I am experiencing is just every now and then. The cast majority of the time it works good and consistent.

 

[cascadian]

So what you are talking about, if it has nickel legs... It it obvious? Like one metal stuck to another obvious? I have a couple coils I'm going to take apart.

It will not be obvious if it is well done. It would be easier to find a joint by tearing apart an unused coil.

And I get what you are saying... But if it was a quality joint, one metal to the other, would that be so bad? Seems the SS section would still be the part being controlled. I don't know though.

Each metal has a different TCR and the legs will not be at the same temperature as the coil so each will be changing at a different rate. At the the welded joint there will be an associated contact resistance. The contact resistance of a welded wire joint can and typically does change with age.

 

[Powerman]

Hummm... well new coils read .25 like they should. then they change to .27-.28. I've seen .3 ohm.

I took my burnt coil apart. the cotton was burnt evenly around the coil. So it wasn't just a spot. It's legs welded to two coils. they lok like the same metal, but what does that prove? The coils are stuck together. I'm curious if the taste issue is associated with bonding. I mean they are welded to the legs, but they are stuck together pretty good.

While I get two wires laid together, I'm not so sure I get welded to one leg. It all looks like the same size wire. I'm not sure what the advantages of "dual" are if it is going through one wire of the same size.

Crappy cell phone pic:

 

[Powerman]

Well poop.... I wasn't searching for the right stuff. This is from Redit:

That would be the nickel wire in question . The legs are not going to have even heat , and obviously would be retaining more of the thermal transfer towards the coil and less towards the insulator.

I sat down when I had some time earlier , thought about it , and looked at data available . Still pretty sure that it will make a considerable difference , more than enough to bring about the "why doesn't this work " posts or the "SS tc sucks" , but doubting enough that its nagging at me to check into it .

I popped one apart and noted what lengths, and diameter(27g r and nr wire) of material are inside , and checked that info vs steam engine to figure out what ss wire they may be using . ( yes I know se is not entirely accurate , but close enough to ballpark this for my personal sanity lol)

If they use 316l for the coil itself , its looking to be about 60f under set temp in the lower ranges , and about 100f if you set for 550 .

I guess the real answer would have to come from a dna 200 owner , who has a crown tank coil (and is willing to tear it apart) and try trapping and firing the wire in an rda. Once at the ss, and once at the ni200 . Both from room temp , same settings and conditions both times .


Ya, that's pretty much it. Why everyone uses the 304 TCR. The nickle legs are throwing it off. In another read, they were locking ohms on a new cool atty and it solved a lot of problems. They talked about how much drift there is on the Crown coils looking at it in "atomizer analyzer" in escribe. Maybe I will try that on my next new coil. This is really a bummer. Maybe the 1.2 single coil would work better... if that one does not have nickle legs.

 

[CorallineAlgae]

Maybe the 1.2 single coil would work better... if that one does not have nickle legs.

I rebuilt a 1.2Ω head a couple days ago. It did not have nickle legs. It was a single strand of what looked like 24 gauge wire with no weld points. Don't quote me on the wire gauge. I didn't measure it, but I just looked at the old coil and it feels thicker and much firmer than the 26 gauge wire that I rebuilt the head with. I have 24 gauge 316L SS wire and the 1.2Ω coil looks similar.
I almost put calipers to it but... tired and lazy. ( ¬‿¬)

Either way, the single coil head did not have nickel legs. I couldn't try to use it for temp control because my mods only do TC below 1Ω.

 

[Powerman]

Cool. Well I have plenty of 0.25 and 0.5 coils. Kind of a bummer if I can't utilize them how I intended. I can run them in power. But they do work most of the time in TC. Even if the TCR has to be juked, it is certainly in the ball park. Still tastes good. It just does its own thing every now and then. Better than the ni200.

If Uwell didn't intend the SS for TC, hopefully they will make one specific for it, or do Ti. Because the ni200 isn't the best. And the tank is certainly a winner.

 

[Vlad1]

Cool. Well I have plenty of 0.25 and 0.5 coils. Kind of a bummer if I can't utilize them how I intended. I can run them in power. But they do work most of the time in TC. Even if the TCR has to be juked, it is certainly in the ball park. Still tastes good. It just does its own thing every now and then. Better than the ni200.

If Uwell didn't intend the SS for TC, hopefully they will make one specific for it, or do Ti. Because the ni200 isn't the best. And the tank is certainly a winner.

I use the .25Ω SS Crown coils on both the SXmini m and the DNA200 in TL mode with the TCR of .00105 as if it were SS304 without any problems. I quickly learnt to lock the resistance on the DNA as something as simple as going from inside to outside ambient temperature would cause Refinement to re-read the resistance much higher than actual and burn the coil and provide a very unpleasant dry hit.

Another automatic feature that may be causing your problem is the DNA may be dropping you out of Temp Limiting mode and directly into Power mode regardless of the Profile you have selected. This feature attempts to detect if you have a Temp Limiting Coil and checks if the resistance of the coil has increased by a certain unknown amount over a certain period of time after firing. It's not stated in the data sheet so I don't know what these variables are but if it doesn't reach them it will drop out of TL mode and go directly into Power mode. Profiles are really only suggested settings the device may decide that's not really what you should have.

One other area that may cause some inconsistent vapor is how Preheat is designed to work. On the first pull when the coil is at room temperaturel Preheat power will be applied to the coil. But on subsequent firings back to back as in chain vaping Preheat determines that the coil is already hot enough and doesn't apply the Preheat power. Due to this the vapor volume is decreased on the subsequent firings after the initial firing.

Of course if there are connection issues with your coil or atty and you haven't Locked Ohms, Refinement will cause the device to fire at very inconsistent Power levels determined by the current coil resistance setting provided by Refinement. While I haven't had any problems with either the Crown pre-built coils or the RBA section the pre-built coils do have a contact compression connection so I could see the potential for having some with connection issues.

 

[Powerman]

I use the .25Ω SS Crown coils on both the SXmini m and the DNA200 in TL mode with the TCR of .00105 as if it were SS304 without any problems. I quickly learnt to lock the resistance on the DNA as something as simple as going from inside to outside ambient temperature would cause Refinement to re-read the resistance much higher than actual and burn the coil and provide a very unpleasant dry hit.

Another automatic feature that may be causing your problem is the DNA may be dropping you out of Temp Limiting mode and directly into Power mode regardless of the Profile you have selected. This feature attempts to detect if you have a Temp Limiting Coil and checks if the resistance of the coil has increased by a certain unknown amount over a certain period of time after firing. It's not stated in the data sheet so I don't know what these variables are but if it doesn't reach them it will drop out of TL mode and go directly into Power mode. Profiles are really only suggested settings the device may decide that's not really what you should have.

One other area that may cause some inconsistent vapor is how Preheat is designed to work. On the first pull when the coil is at room temperaturel Preheat power will be applied to the coil. But on subsequent firings back to back as in chain vaping Preheat determines that the coil is already hot enough and doesn't apply the Preheat power. Due to this the vapor volume is decreased on the subsequent firings after the initial firing.

Of course if there are connection issues with your coil or atty and you haven't Locked Ohms, Refinement will cause the device to fire at very inconsistent Power levels determined by the current coil resistance setting provided by Refinement. While I haven't had any problems with either the Crown pre-built coils or the RBA section the pre-built coils do have a contact compression connection so I could see the potential for having some with connection issues.

Dude, thanks a lot. And that has been my experience too... I just didn't really know it. Seems inside/outside fakes it out. It's been colder here and I thought it was just in my head.

Sooo... If I lock ohms, and the resistance drifts up, then wouldn't the device think it is already hot? Regardless, I can give it a try.

And ya, preheat changes. Me too. Thanks for letting me know it's not just me.

Oh, and I do use 304. Steam engine has it at 1016. But I doubled the points and it seemed to help. But obviously doesn't fix it. Found out you can't do a lot of that because it has very little memory. I was going to drop my power down because I thought I might be in power. I could set that so I don't over do it. I figured it was limiting so power didn't matter.

 

[Vlad1]

Dude, thanks a lot. And that has been my experience too... I just didn't really know it. Seems inside/outside fakes it out. It's been colder here and I thought it was just in my head.

Sooo... If I lock ohms, and the resistance drifts up, then wouldn't the device think it is already hot? Regardless, I can give it a try.

And ya, preheat changes. Me too. Thanks for letting me know it's not just me.

Oh, and I do use 304. Steam engine has it at 1016. But I doubled the points and it seemed to help. But obviously doesn't fix it. Found out you can't do a lot of that because it has very little memory. I was going to drop my power down because I thought I might be in power. I could set that so I don't over do it. I figured it was limiting so power didn't matter.

If you lock the ohms and actual resistance rises it would have to be due to either increased temperature of the coil or a loose connection. But you wouldn't really see that on the display with the resistance locked. You should be able to see it in Atty Analyzer though if you have fluctuating resistance or not. With the resistance locked the board assumes the locked resistance is correct so disregards any creep to some degree that may be due to either to my understanding.

So in your case going outside where it's cooler is opposite of what I experienced this summer when it was hot outside. You probably went from a good vape inside after initial setup then going outside where it was cooler, coil temp went down, resistance went lower on the coil as a result and Refinement lowered the coil resistance on the device causing it to need less voltage to meet the Power setting based on the Refined resistance and provided an anemic vape.

Mine was opposite in going outside when it was much hotter, coil temp went up, resistance went up, Refinement raised the coil resistance and provided more voltage than actually needed and delivered a dry hit, burnt coil. So with Refinement the Power setting is not changing so if the device thinks the resistance has changed it will automatically increase or decrease the voltage being applied to the coil to meet the Power setting that's chosen even if the Refined resistance is skewed due to environmental changes.

 

[BaerCiggy2Vape]

I am running the 0.5ohm ss dc on the uwell crown tank in TC mode on top of my x cube mini, I'm vaping her at 40w(SOFT), my temp is set to 350f, but my TC doesn't let the temp go higher than 250 at most , IT SLOWLY gets up to that temp and usually stays below it. I locked my coil resistance to 0.500ohms, but when I fire it the ohms/resistance fluctuates between 0.500 and 0.550/0.560/0.570/0.580
Then after my drag, it jumps back down to 0.500 which is my initial locked in resistance. Normally the x cube mini reads my coil at like 0.480, but i go into the settings and adjust that every time I use it and set it to 0.500, is that safe? For it to be jumping around when vaping on it, I mean the coil only reads a max of 0.580 during my vape then goes back to the initial setting after I'm done taking a drag.
Anyway. Seems to produce a much more satisfying vape in TC-SS compared to wattage mode.
Much better flavor.

 

[DevAuto]

I have not tried TC with the stock coils, but, if the coils continue to give you too much trouble, I can speak highly for 28g SS-316L, 3mm ID, 5 wraps on the build deck. Performs flawlessly on all my mods.

 

[Ben-Rod]

Atom Vapes has some titanium coils coming out...

 

[CorallineAlgae]

I am running the 0.5ohm ss dc on the uwell crown tank in TC mode on top of my x cube mini, I'm vaping her at 40w(SOFT), my temp is set to 350f, but my TC doesn't let the temp go higher than 250 at most , IT SLOWLY gets up to that temp and usually stays below it. I locked my coil resistance to 0.500ohms, but when I fire it the ohms/resistance fluctuates between 0.500 and 0.550/0.560/0.570/0.580
Then after my drag, it jumps back down to 0.500 which is my initial locked in resistance. Normally the x cube mini reads my coil at like 0.480, but i go into the settings and adjust that every time I use it and set it to 0.500, is that safe? For it to be jumping around when vaping on it, I mean the coil only reads a max of 0.580 during my vape then goes back to the initial setting after I'm done taking a drag.
Anyway. Seems to produce a much more satisfying vape in TC-SS compared to wattage mode.
Much better flavor.

Yes, the resistance should always jump higher as the coil heats up. That's how temp control works. I'm not sure why you raise the resistance in the menu though. I've used these heads in TC many times and they work well without altering the resistance. Personally, I wouldn't bother changing the initial reading at all. Your ohm adjustment could be what is throwing the temperature off on your mod. Even though a head is labeled 0.5Ω it doesn't mean it will be exactly 0.5Ω. You can always lock the ohms in at whatever the initial "cold" reading happens to be. I've had many .5 Crown heads that were both higher and lower than .5. They all worked in TC using the initial resistance.

If you try setting the coil back to 0.480Ω (or whatever your current Crown head reads without modification) please let us know if it works any differently on your X cube.

 

[DevAuto]

Yes, the resistance should always jump higher as the coil heats up. That's how temp control works. I'm not sure why you raise the resistance in the menu though. I've used these heads in TC many times and they work well without altering the resistance. Personally, I wouldn't bother changing the initial resistance. Your resistance adjustment could be what is throwing the temperature off on your mod. Even though a head is labeled 0.5Ω it doesn't mean it will be exactly 0.5Ω. You can always lock the ohms in at whatever the initial "cold" reading happens to be. I've had .5 Crown heads that were both higher and lower than .5. They all worked in TC using the initial resistance.

If you try setting the coil back to 0.480Ω (or whatever your current Crown head reads without modification) please let us know if it works any differently on your X cube.

^^THIS^^ There is a tolerance factor with any mass produced item, and if the initial resistance is anywhere in the ballpark, it could just be the manufacturing tolerance was off when it was produced. I always start with the reading on the mod, and if something doesn't seem right, then I *might* play with the resistance of the coil.

 

[fq06]

SS crown coils rock on TC, just got to bump the tcr up a bit to compensate for the Ni legs... like 105, 110... would have to look, can't remember what I set the memory at.

Coil art said they were adding crown to their lineup, lots of interesting coil styles from them, will try when they come out.

... and yeah, set your resistance at room temp and don't fuck with it. Your mods real time resistance with change while firing the coil.