Weak temp control vape with ISub SS coil

[denniz]

8 minutes ago, awsum140 said:

Given that the accuracy of TC is determined by the TCR values of the specific alloy in use, "playing" with the TCR, IE guessing or trying different values until you get the vape you want, kind of defeats that accuracy and can lead to significantly different temperatures being present.  The result being that device monitor will report the temperature based on that "fudged" TCR and not on reality.  That's why I use, strictly, RBA atomizers and wire from known, reliable, sources.

I also build my own SS coils in a Merlin RTA and then all my problems go away and I can use normal TCR values. But in the case of Joyetech coils, it isn't "playing" around with TCR values, since that's really the default TCR they use for SS coils. Don't ask me why, I just know that Joyetech/Eleaf/Kangertech do it this way. And that's why I think they don't really use SS316, but some other custom SS alloy to be used specifically with there own mods and default profiles.   

Edited November 12, 2017 by denniz

[awsum140]

And that is my point.  Unless the alloy is exactly as advertised the TCR is an unknown quantity and, therefor, so is the actual temperature of the coil.  Given that Evolv is engineered to be accurate, and safe, while most (certainly not all) others are engineered to be "cost effective" I'll stick with Evolv and known wire types.

[denniz]

I agree  

When I got my Joyetech Evic VTwo Mini I always wondered why there manual specifically said to only use Joyetech coils, tanks and mods together and not substitute on of those for another brand. The store where I bought my Joyetech tank (Cubis Pro Mini) said that I could ignore that part of the manual and I could use other tanks on it. Well I now have my answer why Joyetech stated that in the manual. When using there own tank/coils on a non-Joyetech mod, the vape is cold and weak because of the default TCR. On the other side when I use my own build SS coils and RTA tank with the default Joyetech SS316 profile with a TCR of 120, the temperature would actually be to high since then I actually need to use a custom TCR of 88 or 92. 

More standardization would be nice, especially for newcomers these kind of things can create some really confusing experiences.   

 

Edited November 12, 2017 by denniz

[Wayneo]

48 minutes ago, awsum140 said:

... accuracy of TC is determined by the TCR values of the specific alloy in use, "playing" with the TCR, IE guessing or trying different values until you get the vape you want, kind of defeats that accuracy and can lead to significantly different temperatures being present.  The result being that device monitor will report the temperature based on that "fudged" TCR and not on reality.  That's why I use, strictly, RBA atomizers and wire from known, reliable, sources.

@denniz Just to add slightly .... If you look at the composition off what makes SS304 304, or SS316 316, the specs clearly show both minimums and maximums for each wire type designation. If one batch were to follow all the minimums/maximums/average it will all throw off accurate TCR. Not disagreeing with your 120 ........ just saying.

I'm with @awsum140 .... every word.

Edited November 12, 2017 by Wayneo
Agreeing with Awsum

[denniz]

@Wayneo: Below I quoted myself from something I posted on the NFE Team forum who create the ArcticFox firmware for Joyetech/Eleaf/Wismec mods. To bad not even specific SS alloys are created equally, that would make life a lot easier. 

When looking at Steam Engine and the values given by DJLsbVapes the whole combined TCR range for the most common stainless steel grades used for vaping, SS304, SS316, SS316L, SS317, SS317L and SS430, are between 88 en 138. All depending on the specific SS grade that is used. I also know that even specific grades aren't created equally, if we take SS430 for example it's composition is the following (below values are also slightly different depending on the source you check):

Carbon: max 0.12%
Silicon: max 0.75%
Manganese: max 1%
Phosphorus: max 0.040%
Sulfur: max 0.030%
Nickel: max 0.75%
Chromium: between 16% and 18%
Iron: the remaining percentage

[Wayneo]

 

8 minutes ago, denniz said:

To bad not even specific SS alloys are created equally, that would make life a lot easier. 

Much easier for sure. But SS, IMHO has become the defacto standard for many, due to safety fear mongering. I posted a a table below showing composition for each SS 

 

[awsum140]

I guess those variations actually make the case for sticking with titanium, although even there it can vary depending on purity and the other constituents making up the wire.  Even with a known, reliable, supplier we are taking it for granted that their wire is always the same which is highly unlikely.  Heck, there are, undoubtedly, variations in each roll we buy and use.  Hopefully, they're not significant variations.

 

I've felt for a long time that the only true way to get accurate temperature control is with a thermocouple.  Unfortunately, that would require a complete change in connectors and exactly how that thermocouple gets inserted into the coil is another problem.  On the brighter side, that would allow any wire type to be used and still be accurate even with kanthal.

 

denniz, I agree with you that the factory SS coils are probably fine with devices from the same manufacturer and become problematic on other devices because they are, probably, not the alloy as expected.  A vertical coil can cause even more problems.

Edited November 12, 2017 by awsum140

[denniz]

I agree with both Wayneo and awsum140, but since the original poster is using factory oem SS coils, I thought my posts were relevant since his symptoms were exactly the same as mine when using Joyetech/Kangertech factory oem coils. Building your own coils  is a much better way to go, it gives a more consistent experience.  

Edited November 12, 2017 by denniz

[Wayneo]

Yup Yup Yup to ya's.

@awsum140 Last week I was gifted 6@30 foot spools of Temco Ti01, and 1 box of NiFe70. This stuff just doesn't have the market, but Gold to me.

Ni200 is considered commercially pure @ 99.6% Nickel and was used as the material by Evolv on the DNA40's. Also used by Steam-engine as their reference material.

Ti01 is ~99.5%

 

[denniz]

37 minutes ago, awsum140 said:

I've felt for a long time that the only true way to get accurate temperature control is with a thermocouple.  Unfortunately, that would require a complete change in connectors and exactly how that thermocouple gets inserted into the coil is another problem.  On the brighter side, that would allow any wire type to be used and still be accurate even with kanthal.

I actually think this is gonna be the next step in vaping evolution in e-cigs, thermal sensors to actually measure coil temperature and not simply calculating it through TCR's. I believe vaporizers for vaping with dry herbs, like the Arizer Solo II https://arizer.com/solomenu/ already work this way. I'm curious when thermal sensors are gonna make it's way into e-cigs. Because as things stand now, like pbusardo https://www.youtube.com/user/pbusardo says, it's more like temperature guessing. 

[Wayneo]

I can't see it. Maybe as a niche product. There's only 1 standard really, being the 510 connector. From that we get the resistance of any coil/atty combination. I think it's gotta be done through software, a la Hohmtech. Just my thoughts. Think of interchangeability consumer choice.

[denniz]

@Wayneo: Hohmtech mods are nice indeed, I got myself a Hohm Slice. According to Ben (Hohmtech's director) they use EPT (Electrical Ping Timing) for accurate temp control. Too bad the customer service really sucks from them.. with there sucky answers leading to nowhere...

For those who don't know what EPT is:

Quote

Source: http://www.ecigarette411.com/ept.htm

 Here is the explanation from Hohm Tech:

1. EPT: Electrical Ping Timing - As the coils are heated, it is pinged (just like using the internet or when an officer using radar gun). The amount of time it takes for it to get from point A (starting line) to point B (finish line), determines a value. As metal gets hotter, the ping timing changes (in case of the radar gun, means you're traveling at X value speed).

2. Psycoil - this feature is designed to read the gauge wire(s) within a build. It does this by reading the volume and level of current applied to coils. It takes the collective fluctuation of volts/watts to the 1000th position, and pools this information together and compared to EPT values. This results in delivering precise volt/watts to the 1000th position. Future updates will further fine tune and go to 10,000th position of accuracy.

3. Ohm H/L Spread - using resistance spread (basic values of ohm change as metal heats). This spread is calibrated to pull back once coil(s) achieve any value outside of ohm spread as a safety measure to reduce risk of cotton burn.

All 3 values are used to determine and evaluate temperature and aim to prevent cotton burn. Kanthal is without a doubt the most complex of them due to its tremendous sensitivity, but very doable. We'll continue improvements as time progresses."

Edited November 12, 2017 by denniz

[awsum140]

29 minutes ago, Wayneo said:

I can't see it. Maybe as a niche product. There's only 1 standard really, being the 510 connector. From that we get the resistance of any coil/atty combination. I think it's gotta be done through software, a la Hohmtech. Just my thoughts. Think of interchangeability consumer choice.

I've always found the 510/808/EGO/VGO to be kind of marginal, at best, especially from an electrical standpoint.  The variations in center pin projection and exactly how the connection is made between the center pin and the coil become, shall we say, problematic at times especially at the resistance levels that TCR TC works at.  A bayonet or twist-lock style connector would eliminate all of those variables as well as provide an easy way to add more connections.  Yes, an additional connection could be added, coaxially, to the 510 but even that would require an upgrade by all of us "old time" vapers.  It would be a slow, painful at times, process and I can hear the "I'll never change from the 510" tumult even now, but the same was said when VV/VW came along and yet again when TC came along.

 

In the mean time, we're kind of stuck with "fiddly" TC using TCR or the "ping" method.  Both are actually approximations but I do know from folks who have conducted empirical testing that DNA chips with reliable wire are pretty darn accurate.  Just got to get rid of that fiddle factor somehow.

[Wayneo]

On 11/12/2017 at 8:47 AM, denniz said:

Because as things stand now, like pbusardo https://www.youtube.com/user/pbusardo says, it's more like temperature guessing. 

True words. Even here with DNA devices, knowing that we can no longer get an accurate Mod Resistance value from Atomizer Analyzer as we know it. But we do get COLOR screens ........yes!!!. 

[James]

@Wayneo, how far off are you measuring Mod Resistance? On a 60, 75, or 75C it should be able to measure quite low (particularly the 75C). 200/250 don't go below about 5 mOhm right now to protect the fuse, which I do need to work on for a future Service Pack, but given there are no 510s below 3-4 mOhm (Evolv 510 is around 4 mOhm, is there anything lower?), I wouldn't call this the major source of inaccuracy.

[Wayneo]

@James, with the solid copper 510 tool, with multiple 200's using the last 2016/02/23 firmware and escribe 1.0.39 or 42, I was getting down to .002 on a couple mods. Later firmware and escribe was down to ~.006 before a ? mark. The last i checked (if you can tell I'm a mod res natzi) it would get to .005 and stay there, but testing on the prior versions would still get my 11 DNAs .002 and higher. The 75 non color (when tested) managed to show lower values. You said "Always make sure the Mod Resistance you have is conservative", they (users and quality manufacturer's) will think .005 is accurate.

I don't own a C version.

On my BilletBox (only DNA60) it was set at .0004, and no way to validate that or thermal characteristics (even though I only need board temp to room temp offset) as there's no USB port. Telling me another way is more useful, than an easy 'just use the defaults'.

I had a DNA250 custom built, with the shortest, biggest, fattest wires possible for every connection with a shitty Varitube v2 (which is now being replaced) and got .003 using an alternative method.

I'm no Electrical Engineer, but if a '0' value is the default, couldn't you put Mod Res calculation on the Manufacturer Mod tab, and perhaps disable the fire button, allowing us to use the solid copper tool or something? A simple yes or no would suffice. A nice feature would also allow one to Save "Mod" parameters, allowing us to load default settings across the slew, then load individual Mod parameters.

Mod Res setting IMHO is a 'premium feature' parameter from the Temperature vaping pioneer company.

[James]

@Wayneo, if it stays there instead of reading ?, I'll have to check that out. (What you are referring to, starting with DNA 250 1.2 SP5, we implemented quick fuse protections. This resolved a lot of popped fuse failures. That said, it limits output current to 24A only while measuring resistance, but there's a minimum power to consider a resistance reading valid. One way around this would be to allow a minimum current as well. I may try this.)

[Wayneo]

Yes, just stays there as 0.005, no more ?. I noticed the change (stopped working) with my 200's from 1.2 SP3, FDA deadline. IIRC, you limited the max peak and sustained current at 24A, and identified as '-Other changes'.

No comments about anything else?