Very informative and well written piece ... also long ... :)

[scrumpox]

http://www.ecigssa.co.za/guide-to-fine-tuning-temp-control-vaping.t18206/

 

[danb]

http://www.ecigssa.co.za/guide-to-fine-tuning-temp-control-vaping.t18206/

Generally a very nice post, lot's of things there I hadn't really thought about, but there are some problems here:

" Finally, Ni has a very high TCR value - which means that very large resistance changes are observed for each 1 °C increase in temperature. Mods can therefore measure the change in resistance very accurately, and, correspondingly, determine the temperature correctly. The result is a very clean and absolutely temperature controlled, smooth vape, with almost undetectable changes in power, which more than makes up for the difficulty in building with it."

"It [Ti] has a TCR value roughly half of Ni’s, which means it is not as accurate"

These statements are misleading because they ignore the effect of baseline resistance on TC accuracy (which I explain here). The high TCR of Ni200 doesn't result in "very large resistance changes" because the baseline/initial resistance is very low. The TCR of Ti is almost half that of Ni, but the resistivity of Ti is almost 5x that of Ni. Taking the baseline resistance into account, the resistance change of a Ti coil is almost 3x higher than Ni coil when comparing otherwise identical builds - so Ti is almost 3x as accurate as Ni. Steam engine also calculates this - the TC precision value in the wire wizard tab.

It's true that a 0.2 ohm Ni coil (25 wraps of 26g at 2.5 mm ID) is more accurate than a 0.2 ohm Ti coil (5 wraps of 26g at 2.5 mm), but the comparison is not useful because these are totally different builds.

 

[Mr Numpty]

And that's why I go to @danb for all my TC needs.

 

[scrumpox]

Yes, and I'll leave @danb to argue the toss with the author.

It's a very long but useful read for someone new to TC vaping and whilst there might be points to argue about it gets the main points over pretty well. He obviously has some more detail to add as he's left marker posts in his thread.

The author did also touch upon the main topic which interests me ... not so much the technical detail but the difference in the vape experience. To many vapers, TC is antirely about the avoidance of dry hits which is a shame really. It's like saying the pleasure of driving an automatic car instead of a manual is avoiding a crash. You don't need TC to avoid dry hits, you only need to know the very basics of vaping. The difference in the vape delivery and the way it can be customised - or calibrated - is what's interesting about TC. I think about power mode as manual temp control and TC as automated temp control. Where the motoring analogy falls down is that in vpaing automatic currently means a lot more faff than manual. It's still an emerging tech and all the while vapers have to negotiate Escribe and SXiQ we remain on the nursery slope.

 

[Mr Numpty]

I enjoyed the article and definitely useful for anyone new to TC. Had to laugh at him saying English wasn't his first language and that his language skills were horrible anyway, considering how well written it is. I'd love to have such a "poor" grasp of a foreign language.
I have to think it's an indication of just how much I'm wasting my time that I already had a fairly full understanding of what he was saying, including the misleading info on NI/Ti. Must seek new interests.

 

[allen]

"while vapers have to negotiate Escribe and SXiQ we remain on the nursery slope."
I have a very strong suspicion I'm going to regret this next statement.......
My first DNA purchase is still in China but I've downloaded escribe and been playing with it.
I've added Nife 30 and 48 as new materials and set up a couple of prfiles with those materials; I found the software very easy to use.
Now I just need to receive the mod and see if I did it correctly

The post linked at the top seems well written with some useful stuff in there - so thanks for the link @scrumpox

 

[scrumpox]

"while vapers have to negotiate Escribe and SXiQ we remain on the nursery slope."
I have a very strong suspicion I'm going to regret this next statement.......
My first DNA purchase is still in China but I've downloaded escribe and been playing with it.
I've added Nife 30 and 48 as new materials and set up a couple of prfiles with those materials; I found the software very easy to use.
Now I just need to receive the mod and see if I did it correctly

The post linked at the top seems well written with some useful stuff in there - so thanks for the link @scrumpox

Yes, but I'm not thinking about the small percentage of vaping geeks who frequent forums, I thinking about the mainstream. Most of the vapers I know struggle with understanding VV/VW mods and their eyes glaze over once the words resistance, watts and amps are uttered in a sentence. They don't build, they don't make their own juice and they certainly don't expect to calibrate their mod via bluetooth or a USB cable.
I'd like to think that there's a future which includes the mod auto-recognising the wire, where TC is no longer a thing at all ... when we will be talking intuitively about heat and airflow instead of Ohm's Law, TCRs, voltage drop and resistivity. There will always be the small percentage of geeks who want to understand how anything works in fine detail but mainstream devices have to be simple to operate. KISS will always win the day.

Enjoy your DNA when it arrives ... I'm enjoying my SX Minis.

 

[allen]

I'd like to think that there's a future which includes the mod auto-recognising the wire, where TC is no longer a thing at all ... when we will be talking intuitively about heat and airflow instead of Ohm's Law, TCRs, voltage drop and resistivity. There will always be the small percentage of geeks who want to understand how anything works in fine detail but mainstream devices have to be simple to operate. KISS will always win the day.

Enjoy your DNA when it arrives ... I'm enjoying my SX Minis.

With you on the auto-recognising..... It shouldn't be thay hard to do.
Have a 'set button' that measures initial resistance, fires at low wattage, measures change in resistance and selects wire type based on that change. Or am i deluded in thinking it could be that simple?
I suppose things like claptons would screw it up though.

 

[danb]

Have a 'set button' that measures initial resistance, fires at low wattage, measures change in resistance and selects wire type based on that change. Or am i deluded in thinking it could be that simple?

For auto recognition you basically need a mod that can measure the TCR of the wire. There are three variables in the chip's calculations, 1. Resistance, 2. TCR, 3. Temperature.

To calculate any one of those three, you need to know the other two. Firing at low wattage across an unknown coil allows you to measure resistance change, but results in a very approximate temperature change. Sure you could probably tell the difference between Ni, Ti and SS (actually I seem to remember there are mods that claim to be able to do this already), but you won't be able to distinguish Ti from NiFe48, probably not Ni from Stealthvape NiFe30. The only way I can see to actually calculate TCR accurately is to measure temperature directly and compare it to resistance change - but if you can directly measure temp, you no longer need to do temperature calculations and TCR becomes irrelevant (and TC would work with any wire you like).

I think that's really hard to do though. Assuming you could fit the hardware into the atty, a contact temperature probe will probably disrupt airflow and/or wicking, and a non contact probe (IR sensor) probably won't penetrate the vapour to see the actual coil. But I'm no expert in temp sensing technology, and most things that appear to be impossible usually are achieved eventually...

 

[Mr Numpty]

Very interesting, Dan.