New studies find carcinogens in vg and pg at high temps, even in tootle puffers

[mikepetro]

Very interesting, could you please say again what wire was used in this accuracy test? I'm not sure which initial post stated that.

Thanks for all your efforts

It was a 3mm, 5/6 wrap, of 26awg SS430, using the TCR from the Steam-Engine site.

 

[Eskie]

I happen to reside in NC at this time , not a happy camper right now.

You can always move.

Besides, no one really knows the extent of risk at every activity we might partake in. Someone always knows someone who great grandfather was out splitting wood for the stove at 95 and smoked two packs of unfiltered Camels a day. The chances of being that guy are really, really low if we had kept smoking (maybe even just with whatever all the years of cigarettes we smoked did to us). Some folks are fortunate to win the genetic lottery and some don't. As much as we can collect genetic information and sequence your entire genome for not all that much money these days, we still can't identify what's in there that we wish we did have to be like that guy's great grandfather.

 

[ndb70]

It was a 3mm, 5/6 wrap, of 26awg SS430, using the TCR from the Steam-Engine site.

Got it, thanks!

 

[mikepetro]

Interesting, would love to have known what wattage he was using for these tests.

 

[mikepetro]

I "hope" to get a little more accurate than this, but it is interesting:
I wonder what he was using for nic, his boiling point looks lower than 477F.
Also notice his flavoring got hotter than the PG.

 

[mikepetro]

I think I may have just saved myself a bunch of work. I found a chart of mixed PG/VG boiling points.

Here is his blurb that gets into fractional distillation.

I prepared this chart using VMG Sim chemical simulation software for a propylene glycol / glycerol mix. Unless you're a chemist, you might not have seen this type of chart before, so let me explain how it goes:

The lower curve, in blue, is called the bubble point. For any mix of PG-VG (along the bottom axis), this curve shows the temperature at which it will begin to boil (or as we know it, vapourise).

Example: A 50/50 mix starts to boil at about 208 degrees C (406 F). But the vapour that comes off at this point isn't 50/50.

Trace a line straight across to the orange curve. This is the dew point curve, and among other meanings, it shows the composition of the vapour that boils off a given liquid mix.

Note that for a 50/50 liquid, the first bit of vapour is more like 95% PG

So now we've just cooked off more PG than VG, in the very first tiny fraction of a puff. So what's left isn't 50% PG anymore; it's more like 49.9999...%. Trace the line again, and this time the vapour isn't 95%, it's 94.9999...%. And that's the second tiny fraction of a puff.

As the tank gets vaped, more and more PG leaves and more and more VG gets left behind, as we slowly migrate left on the curves. This is exactly the same idea as distilling alcohol from water: you can start with a 15% brew, but what you distill isn't 15% alcohol; it's much higher. If you leave it to boil, eventually you'll cook off everything and be back with your original composition (now vapourised).

Eventually, we move all the way to the left of the curve: the last puff is 0% PG, vapes at 280 C, and the vapour is also 0% PG, 100% VG.

Not sure if other people notice it, but my vapes pick up a distinctly sweet VG taste and lose throat hit as the tank goes. And the above is why.

PG boils off easier than VG, just like distilling alcohol from water. As you go through a tank, it gets more and more VG-rich

This is the software mentioned: VMG Empowering Process Simulation

 

[zoiDman]

I think I may have just saved myself a bunch of work. I found a chart of mixed PG/VG boiling points.

Here is his blurb that gets in fractional distillation.




This is the software mentioned: VMG Empowering Process Simulation

Interesting Blurb.

Do you have a Link to where it came from?

 

[mikepetro]

Interesting Blurb.

Do you have a Link to where it came from?

https://www.google.com/url?sa=t&rct...lroKx7pISwq5yridw&sig2=l53cWl_KsvzqpEEOaCFGCg

 

[zoiDman]

https://www.google.com/url?sa=t&rct=j&q=&esrc=s&source=web&cd=6&cad=rja&uact=8&ved=0ahUKEwjUo4adj9nTAhUB5SYKHYJTD80QFghWMAU&url=https://www.reddit.com/r/electronic_cigarette/comments/204n54/ever_notice_a_tank_gets_more_and_more_vgish_as_it/&usg=AFQjCNEGrVyI8Eig5lroKx7pISwq5yridw&sig2=l53cWl_KsvzqpEEOaCFGCg

Thanks Mike.

 

[awsum140]

I guess I'm missing something, but what was the point of those tests from Farsalinos? No specs on anything other than a DMM reading temperature isn't very informative other than seeing the progressively higher temperatures at each step.

 

[mikepetro]

I guess I'm missing something, but what was the point of those tests from Farsalinos? No specs on anything other than a DMM reading temperature isn't very informative other than seeing the progressively higher temperatures at each step.

I didnt say it proved anything.... It was just interesting seeing Dr F drive the Mod that hot in what was clearly NOT a dry hit.

 

[Lessifer]

I think I may have just saved myself a bunch of work. I found a chart of mixed PG/VG boiling points.

Here is his blurb that gets in fractional distillation.




This is the software mentioned: VMG Empowering Process Simulation

I'm wondering if the full effect applies since what is being heated is a very small fraction of the liquid, just what's near the coil, and that is traveling up the wick and not sitting in a tank. Do pg/vg wick at different rates, and if so, does that have an effect on the composition of liquid at the coil?

In my mind, this graph and the explanation make sense if you were heating a pot of 50/50 or whatever, but possibly not in the application of heating a coil/wick, or at least not to the same degree.

 

[mikepetro]

I'm wondering if the full effect applies since what is being heated is a very small fraction of the liquid, just what's near the coil, and that is traveling up the wick and not sitting in a tank. Do pg/vg wick at different rates, and if so, does that have an effect on the composition of liquid at the coil?

In my mind, this graph and the explanation make sense if you were heating a pot of 50/50 or whatever, but possibly not in the application of heating a coil/wick, or at least not to the same degree.

I agree, probably not the same rate as shown in the simulation.

However this does make a lot of sense. It explains why the bottom of the tank is always thicker.

I have noticed that I tend to increase temp settings over time. I had always chalked it up to the coil getting gunked up, figuring thermal transfer declined with crud build up. The wire (resistance) might be 420, but a dirty coil (ie insulated coil) might only be transferring 400 degrees. I convinced myself this was true as after I pulled the wick and did a dry burn, I could return to lower temps again. With rayon I never see much wick degradation so I didnt think the wick had much to do with it.

But..... generally, if I went through the trouble to dry burn and rewick, I almost always rinsed the tank out at the same time, thereby getting rid of the thick stuff at the bottom of the tank.

No doubt it gets thick at the bottom. I tend to refill when I am down to a quarter tank or slightly less. Doing this over and over, I wonder what ratio the juice would analyze out to be after 5 refills?

 

[VapNMirrors]

I'm wondering if the full effect applies since what is being heated is a very small fraction of the liquid, just what's near the coil, and that is traveling up the wick and not sitting in a tank. Do pg/vg wick at different rates, and if so, does that have an effect on the composition of liquid at the coil?

In my mind, this graph and the explanation make sense if you were heating a pot of 50/50 or whatever, but possibly not in the application of heating a coil/wick, or at least not to the same degree.

There's no requirement for how much volume of liquid is needed. If it gets hot it will boil with a fractional vapor composition and more VG will be left on the wick. However, PG being less viscous may be able to flow through the wick faster which would lead even more VG left behind over time, until we suck the tank dry at least.

I suppose we could setup wick races between VG and PG. Yay, more science!

 

[mikepetro]

I suppose we could setup wick races between VG and PG. Yay, more science!

I did something like that once. Poured colored juice in a Genny tank with three different ceramic wicks to see which ceramic wicked better.

60 grit alumina oxide won.......

 

[mikepetro]

There's no requirement for how much volume of liquid is needed. If it gets hot it will boil with a fractional vapor composition and more VG will be left on the wick. However, PG being less viscous may be able to flow through the wick faster which would lead even more VG left behind over time, until we suck the tank dry at least.

Now, throw nic into the mix. I am "assuming" it would boil out faster than VG but slower than PG.

Are we getting different doses of nic (per hit) from start to finish on a tank?

 

[Alien Traveler]

I think I may have just saved myself a bunch of work. I found a chart of mixed PG/VG boiling points.

Here is his blurb that gets into fractional distillation.




This is the software mentioned: VMG Empowering Process Simulation

It's a very (VERY) rough approximation of real processes during vaping. Our coils/wicks should be described by non-equilibrium thermodynamics, rather complex scientific system. Final result should be the same - more VG in remnants of liquid, but not as much as described by this simulation.
It should be very easy to check: vape 3/4 (or 9/10) of your tank, make chemical analysis of what was left. But it looks like nobody bothered to do it.

 

[VapNMirrors]

Now, throw nic into the mix. I am "assuming" it would boil out faster than VG but slower than PG.

Are we getting different doses of nic from start to finish on a tank?

That's true and yes it's getting distilled too. Using a tank, if you've ever watched it drink (where air is pulled back in from the wick) and seen it containing vape then you've directly observed distillation (of everything toward the least volatile).

 

[David Wolf]

https://www.google.com/url?sa=t&rct=j&q=&esrc=s&source=web&cd=6&cad=rja&uact=8&ved=0ahUKEwjUo4adj9nTAhUB5SYKHYJTD80QFghWMAU&url=https://www.reddit.com/r/electronic_cigarette/comments/204n54/ever_notice_a_tank_gets_more_and_more_vgish_as_it/&usg=AFQjCNEGrVyI8Eig5lroKx7pISwq5yridw&sig2=l53cWl_KsvzqpEEOaCFGCg

The responses at your link are worth reading. Applying this curve directly to vaping a PG/VG mix is IMHO based on the comments another misapplication . If anyone believes that a 50/50 pg/VG mix is 75% VG after vaping half a tank I have some cheap land for sale in antartica
Stick with your assumption that you have to increase your TC temp due to coil gunk buildup and you're on track, for that is indeed the case based on heat transfer through the insulating properties of the gunk.

 

[VapNMirrors]

If anyone believes that a 50/50 pg/VG mix is 75% VG after vaping half a tank I have some cheap land for sale in antartica
Stick with your assumption that you have to increase your TC temp due to coil gunk buildup and you're on track, for that is indeed the case based on heat transfer through the insulating properties of the gunk.

Yes, that's for sure. Coil gunk and it's mass/insulator are a far more significant factors. Just to say that distillation is occurring should not be confused with saying that it happening in a significant, tasteable, or even measurable, way, at least within a few ml tank. Now a 20ml Modfather? you might be able to measure the effect on that.

I've found that running a tank a long time with many refills at ~20% remaining and finding over time that the liquid does thicken and dumping it to wash the tank at that point. So it's not completely insignificant.