TC beyond Ni200: Nickel Purity, Dicodes; Ti, SS, Resistherm NiFe30; Coefficient of Resistance

[funkyrudi]

So with np is 10-100 equivalent to 0.001-0.10 tcr? Is that the range of most tcr adj mods but without the .xxx1 accuracy?

No, you have to set the NP about 10% higher on the SXK - on lower NP values even more. For ss 12 or 13 - given that there is no static resitance.
You can make a dry cotton test to find out the NP. But not all kind of cotton or fiber get at the same temperature brown. Muji needs 30-40F more temperature to get as brown as a my bio cotton.

 

[TheBloke]

No, you have to set the NP about 10% higher on the SXK - on lower NP values even more. For ss 12 or 13 - given that there is no static resitance.
You can make a dry cotton test to find out the NP. But not all kind of cotton or fiber get at the same temperature brown. Muji needs 30-40F more temperature to get as brown as a my bio cotton.

Do we know this is true also on later SXK mods? On my first/second batch SXKs, with the low resistance issue, I have to do this. But later batches have fixed resistance, so I was thinking it would now be an accurate NP setting?

Anyway the range is theoretically 0.001 - 0.01 but with some inaccuracy

With SS I set mine to first/second batch SXKs to 10, 12-13 gives risk of dry hits (the TCR of SS is generally a bit below 0.001)

Thanks for the post about the NiFe27! Looks very similar to Kanthal NiFethal70/30 in terms of resistance, but TCR a bit lower. Glad it's reasonably priced.

The NiFe revolution is here!

 

[funkyrudi]

Do we know this is true also on later SXK mods? On my first/second batch SXKs, with the low resistance issue, I have to do this. But later batches have fixed resistance, so I was thinking it would now be an accurate NP setting?

Anyway the range is theoretically 0.001 - 0.01 but with some inaccuracy

With SS I set mine to first/second batch SXKs to 10, 12-13 gives risk of dry hits (the TCR of SS is generally a bit below 0.001)

Thanks for the post about the NiFe27! Looks very similar to Kanthal NiFethal70/30 in terms of resistance, but TCR a bit lower. Glad it's reasonably priced.

The NiFe revolution is here!

You are right, I have V1+V2 version with the ohm issue only. I used ss on a Flash e Vapor with NP13 and still have ss on a Rose set to 12 - no dry hits so far, and I forget to open the LC quite often . But I don`t use 316 or 317, I use V2A/304 with a little bit higher TCR

 

[TheBloke]

Your right, I have V1+V2 version with the ohm issue only. I used ss on a Flash e Vapor with NP13 and still have ss on a Rose set to 12 - no dry hits so far, and I forget to open the LC quite often . But I don`t use 316 or 317, I use V2A/304 with a little bit higher TCR

Ah fair enough

I bought some 304 recently but have not got around to trying it.

 

[vapealone]

Using grade 1 Ti I was unable to get satisfactory results using SteamEngine's CSV but was able to get good results using SSV's beta CSV but thought the temp was way off. So I kind of made one that's in between the two and used the cotton burn test to insure that it was offering good TP protection. I'm using primarily Taifun GT II's and GS II's @ 28 watts with 35 watt pre-heat @ 450F
Here a live view:

Here is the text from my CSV:
-100 0.670714796
0 0.864388704
70 0.999953628
200.1707458 1.409998178
299.5446777 1.589999437
400 1.779981732
500.3414917 2.09999156
600 2.24000001
800 2.344801426

I'm certainly not saying the other CSV's are wrong, I just can't get them to work properly. Comments?
Oh, what was happening with Steamengine's CSV was temp was hit almost immediately bringing wattage down to around 18 watts, all rather too quickly.

I am having some issues too. But for Ti I have ruled out questioning both the CSV and the wire purity too. Mainly because it is working like a charm on a dripper
ATM my prime suspect is the mod body vs Evolv room temperature reading match. Something is just not quite right there.
Besides, I am pretty new to vaping on a DNA200 and until now, I didn't really worry about the actual temperature reading but to get my preferred vapor w/o any dry run.
Now, it is changing, and trying to identify a temp (range) and calibrate accordingly.
P.S.: In terms of CSV, I use my own too because Steam-engine seems to use specimen 1a which apparently have higher purity (and lower resistance) than any commercial grade thus higher TCR, TFR etc.
PP.S.: Just to make the calibration a bit more challenging I am experimenting with new PG/VG ratios too. It is funny to see for real how the required temperature goes up from 210C(410F) to 260C(500F) as I increase VG

 

[TheBloke]

Guys, I have some doubts about Steam Engine's Titanium TCR as well. I haven't tried it on a DNA 200. But I noticed on the Wire Wizard page that it shows the TCR at vaping temperature as 0.00369.

But I have temperature measured on the Dicodes at 420-350 (0.0042 down to 0.0035) and hit exact temp at 0.0035 and was over-temp at 0.0037 and above.

So there is some kind of difference there between the figures Steam has and real-life figures. I will do more temp measuring in future. For one thing I only measured at I think it was 210°C - I can't imagine it then varies hugely up to 250°C, but it might a little.

If you continue having problems with the CSV, I'd try putting in a single TCR figure to eScribe with 0.0035 as a start point.

 

[vapealone]

Here is the text from my CSV:
-100 0.670714796
0 0.864388704
70 0.999953628
200.1707458 1.409998178
299.5446777 1.589999437
400 1.779981732
500.3414917 2.09999156
600 2.24000001
800 2.344801426

I had a second look and now I am confused.
The TFR data you have listed indicates TCRs way higher than any Ti I have ever seen.
TI as an element has a nominal TCR of 0.0043 which refers strickly to 0-100C (The TCR of most of the materials are decreasing with temperature. Ni200 is an exception)
And it is for 100% pure element. Not a commercial grade material.
If I didn't mix up any conversions than your TCRs look like this:
TCR(70F-200.1707458F):0.00566945142600543
TCR(70F-299.5446777F):0.00462654589616738
TCR(70F-400F):0.00425444581090909
TCR(70F-500.3414917F):0.0046009619016246
TCR(70F-600F):0.00421132078867925
TCR(70F-800F):0.00331594872164384
The resistances in this report would give you far lower TCRs in the vaping range, however 800F value looks all right.

Assuming (again) that I didn't screw neither the F-C conversion, nor the TCR calculation, my opinion is that it is not the TCR you have issue with.
Have you tried a dry cotton test w/ this CSV? On 400F, no mark should be left at all.

 

[dwcraig1]

I had a second look and now I am confused.
The TFR data you have listed indicates TCRs way higher than any Ti I have ever seen.
TI as an element has a nominal TCR of 0.0043 which refers strickly to 0-100C (The TCR of most of the materials are decreasing with temperature. Ni200 is an exception)
And it is for 100% pure element. Not a commercial grade material.
If I didn't mix up any conversions than your TCRs look like this:
TCR(70F-200.1707458F):0.00566945142600543
TCR(70F-299.5446777F):0.00462654589616738
TCR(70F-400F):0.00425444581090909
TCR(70F-500.3414917F):0.0046009619016246
TCR(70F-600F):0.00421132078867925
TCR(70F-800F):0.00331594872164384
The resistances in this report would give you far lower TCRs in the vaping range, however 800F value looks all right.

Assuming (again) that I didn't screw neither the F-C conversion, nor the TCR calculation, my opinion is that it is not the TCR you have issue with.
Have you tried a dry cotton test w/ this CSV? On 400F, no mark should be left at all.

Re dry cotton test, yes I did, not until 450 F does it leave a mark and at 450 it can hardly be seen.

 

[vapealone]

Re dry cotton test, yes I did, not until 450 F does it leave a mark and at 450 it can hardly be seen.

What is the PG/VG ratio of your liquid?

 

[dwcraig1]

I just did a dry cotton test again just now, same results as above. Had to look at it with a magnifying glass to even see the scorch.

 

[dwcraig1]

What is the PG/VG ratio of your liquid?

75pg/25vg

 

[dwcraig1]

Here's with Steamengine's Ti CSV

 

[vapealone]

75pg/25vg

Bummer, for 75/25 450F should be all right.
Running out of ideas
So I tell you what I am struggling with ATM:
For some reason, my DNA200 room temperature reading is a bit off. It thinks the room warmer than it is and underestimates cold ohms accordingly.
The 10-15F it is off by, means significantly bigger error at higher temperatures for the TCR decreases. Thus, I manually add the temperature and lock it. And will run a case analizer probably tonight

 

[dwcraig1]

It vapes fantastic the way I have it and appears to offer good temperature protection but why I have to alter the file confuses me to no end. This is with multiple atties. I haven't this problem with nickel. Oh wait, I'm not using a CSV file for ni200.

 

[tchavei]

I'm using these values since the beginning and it vapes just fine:

Temperature (degF) Electrical Resistivity
-100 0.6707249584947427
0.00 0.8644161593801882
70.00 1.00
200.00 1.2517985611510791
400.00 1.6391809629219702
600.00 2.026563364692861
800.00 2.413945766463752


Regards
Tony

Sent from my keyboard through my phone or something like that.

 

[WickedWicks]

Resitherm 0.28mm/ 5.5Ohm/m
Zivipf NiFe30 0.28mm = 3.314 Ohm/m

What would be the 0.28mm equivalent of NiFe52? Even higher than Resistherm?

 

[dwcraig1]

I'm using these values since the beginning and it vapes just fine:

Temperature (degF) Electrical Resistivity
-100 0.6707249584947427
0.00 0.8644161593801882
70.00 1.00
200.00 1.2517985611510791
400.00 1.6391809629219702
600.00 2.026563364692861
800.00 2.413945766463752


Regards
Tony

Sent from my keyboard through my phone or something like that.

Here is my live view using above settings:

 

[tchavei]

Here is my live view using above settings:

Looks good to me. The amount of watts delivered will vary according to your wick tightness and juice delivery to cool down the coil.

We can't really try to match the TCR to a certain wattage / temperature we want. A wire has a certain tcr which allows us to estimate a certain (hopefully correct) temperature.

With my values, at what temperature does dry cotton start to scorch? It should be around 420F when you see some light brown streaks.

Regards
Tony

Sent from my keyboard through my phone or something like that.

 

[dwcraig1]

Looks good to me. The amount of watts delivered will vary according to your wick tightness and juice delivery to cool down the coil.

We can't really try to match the TCR to a certain wattage / temperature we want. A wire has a certain tcr which allows us to estimate a certain (hopefully correct) temperature.

With my values, at what temperature does dry cotton start to scorch? It should be around 420F when you see some light brown streaks.

Regards
Tony

Sent from my keyboard through my phone or something like that.

@ 440 F no scorching, @ 450 F very slight

 

[cigatron]

I agree, a juice transport issue. And/or airflow. Both can cause dimished wattage. Tc is great for dialing in my wicking method. With temp fixed and regulated I can view my wattage while looking in a mirror. I take 4-5 sec pulls to see how well the juice supply is keeping up. Small changes in wicking density or orientation can make sizeable differences in power delivery with my STmini V1 RBAs. The best I've achieved so far with the STminis on my VT60s is hovering at around 30w at 510°f with 75vg on a Ti build. Not sure exactly what the "real" temp is; maybe somewhere around 420? I have definitety been schooled by temp control on how to wick for power.