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Vaporization temperature dependent selection of effects

Discussion in 'Vaporization Discussion' started by tdavie, Feb 2, 2010.

  1. Persian

    Persian Member

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    3
    pretty important thread for volcano users
  2. Trilldo

    Trilldo Member

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    4
    I haven't read this whole thread yet, but bookmarked it, because this is exactly the kind of info many of us need. But I do wonder if the same thing happens with different strains. I do know that research is being done to determine which strains are better for pain, which for nausea, etc. I'm at a disadvantage because I am not able to choose or even know which strains I am using, + this is another reason I want a Pax (well, I guess there are ways to regulate and monitor temp with the mflb, but a friend of mine is doing that particular research for us. it's nice to split the research load!)

    Anyway, thanks. When I am able, I'll post the results I have. As a low-dose chemo patient, maybe I can help.
  3. enthulhu

    enthulhu Member

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    2
    I just wanted to say THANK YOU for this information.
    Tested and confirmed!

    I have always used my EQ at 210c (almost a year now).

    After reading this, I turned it up to 230c for the first time ever, and I have never gotten that high from my EQ after 1 elbow pack...:D

    To further confirm this, it would make sense why my ABV brownies are super couch lockers, all that sedative stuff in the higher ranges has been unvaped and concentrated...

    Also, here is a link to the original source
    http://www.omma1998.org/McPartland-Russo-JCANT 1(3-4)-2001.pdf

    Protip for the high temp:
    The glass mouthpiece the EQ comes with fits air tight into a cheap acrylic Graffix bong, so you can enjoy ice cold humid vapor!
    CA5H likes this.
  4. gb902

    gb902 Vaporog

    Messages:
    129
    Higher temp = better energetic high for me.
    I have always noticed that the first vape session (with fresh bud), gives me a dizzy and uncomfortable effect, even if I keep the temp low (I use the VG classic). But the next session (after a day or so), when I re-grind the same bowl, I get a much powerful and nice high, and it doesn't make me sleepy and lazy.
    I remember that many of my best highs ever, comes from brown ABV, vaped at very high temp (until it turns in a dark brown powder, not black or combustion traces left).
    Recently I finished my fresh stuff, so I grinded some brown ABV as much as possible, then made a single but long hit (I felt the urge to cough, but still inhaling) and hold it for more than 1 minute (with a little rebreathing). The result was a very strong high, both body and head, really funny and introspective. It was night, after a working day but surprisingly I didn't feel lazy.
    I never got that powerful effect from fresh bud, no matter how much I vape (usually, greater quantities gives me only the urge to sleep).

    Last week I have found the Dr. Hornsby experiment, and now all makes sense.
    But I can't understand why so many people are still talking about the "low temp energetic high"...
  5. fubar

    fubar Ancient and opiniated inhaler

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    91
    Location:
    Sydney, Australia
    This is a great thread and since we're talking about extraction temperature, it got me thinking that we should not take the digital readout (or the manufacturers claimed temp preset) as being the temperature we're vaping at - it's more complex than that! For example, if you've ever used one of those dual digital ceramic heater whip style machines, the set temperature stays at whatever you've wound it up to, but the temperature of the hot air going into the whip swings wildly - dropping quickly during each draw and gradually climbing back up to the set temperature between draws.

    I'm a coffee geek and I think making espresso is sort of like vaping coffee but using hot high pressure water. To get consistently good espresso, temperature control is one of the major challenges and one thing you learn about making espresso is that the 'temperature' showing on the digital readout of the PID is nearly always an overestimate of the actual temperature of the water that's hitting the puck - hot water meets cold ground coffee inside a (prewarmed!) metal portafilter inside a big hunk of prewarmed brass, all subject to convection and radiant heat loss.

    I'm going to bet that the temperature you record inside the plant material will vary wildly during every draw - depending from second to second on (eg):
    • the temperature 'set point' and the mechanics/electronics controlling the heating element
    • how much moisture is left in the bud (google latent heat of evaporation) - this changes during each draw as it all eventually evaporates
    • how hot the air is coming in from the heating element (which depends in turn on..)
      • how fast you are drawing
      • how much heat the heating element is generating
    By analogy with coffee, AFAIK, the only way to really know exactly what 'temperature' you are vaping at would be to record the temperature using (eg) a thermistor placed inside the vegetable material!

    That's what some extreme coffee freaks do - you can get a thermistor (scace device eg) fitted inside your portafilter so you can monitor exactly what's happening in the puck as you pull the shot.
  6. SD_haze

    SD_haze MMJ Vaporist

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    3,038
    Location:
    San Diego, CA
    That's a big yup on digital readouts. Certainly one of the reasons the expensive Vapexhale Cloud only has a mechanical-dial temperature control, and not a numerical readout.
  7. fubar

    fubar Ancient and opiniated inhaler

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    91
    Location:
    Sydney, Australia
    Funny thing is I like digital readouts and use them all the time to try to improve my technique - I don't think they can do much harm as long as you remember they don't mean what they say. My espresso machine has a simple computer PID to control the temperature. I usually use a plug in vape - old style dual digital ceramic whip model to control what range of volatiles I'm getting.

    My 2c worth: the temperature selection of specific molecules is probably nature at work so consistent, but strains have characteristic content profiles at each temperature so some eg skunks seem to yield more vapour at higher temps than sativa varieties which have more of the whacky at lower temperatures. YMMV

    Do any commercial vapes use a PID to get hot air to a prespecified temperature?
  8. Vape-Nation

    Vape-Nation Leader of Vape-Nation

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    Location:
    SF
    Is there some research someone can point me to about temperatures and effects? I don't understand how the two correlate, I would expect different effects from different strains. But how does temperature affect the feeling one gets? It's releasing the same chemicals.

    Call me a skeptic on this in the mean time.
  9. fubar

    fubar Ancient and opiniated inhaler

    Messages:
    91
    Location:
    Sydney, Australia
    Excellent. Stay skeptical but do your own experiments - I've convinced myself that I can feel different effects by using different temps but the differences are in terms of psychoactives so subtle, varying with the material to hand, hard to pin down and above all subjective. YMMV. That subjectivity makes it even harder to do good scientific research because valid and reliable measurement is much tougher - eg 'stoned' is much harder to pin down than blood pressure or heart rate.

    AFAIK, there's almost no useful scientific research because cannabis is not an NIH priority research area (eg you won't see it on the NIMH research priorities page at http://www.nimh.nih.gov/research-fu...ties/nimh-strategic-research-priorities.shtml) and no sane drug company would pour money supporting research into something they can't legally control with a thicket of patents.

    All is not lost - there's the known chemistry and physics (eg boiling point) of the some of the active ingredients (see the start of this thread) from which you can make your own guesses and experiment to form your own conclusions about what works for you. I think it's mostly that kind of playful experimental experience ("let's see what happens when I turn the dial down a few notches") that people are discussing in this thread. Ultimately it's going to be a subjective and personal judgement - I don't think anyone has a monopoly on the truth and we're probably talking more art than science here!
  10. Hippie Dickie

    Hippie Dickie The Herbal Cube Manufacturer

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    several do ... cloud and solo for sure.

    i do in my non-commercial homemade vape.

    that's what i found ... i stuck a probe into the herb during a vape session. The setpoint was 380°F, but the temp inside the herb was 50°F lower. During a toke, the temperature would rise to the setpoint -- this took less than 5 seconds. The herb temp dropped after the toke.

    The setpoint is the absolute maximum temperature of the air that will hit the herb.

    my pid will maintain setpoint within 1°F regardless of toke volume or speed. however, there is better extraction from the trichomes -- i.e. more vapor produced -- with a slow, steady inhale.
    vorrange and fubar like this.
  11. fubar

    fubar Ancient and opiniated inhaler

    Messages:
    91
    Location:
    Sydney, Australia
    You are my hero, Hippie Dickie - sticking a temp probe into a wad of bud is heroic enough but having the presence of mind to remember what happened while you took a few draws is the mark of a truly dedicated scientist :bowdown: Your findings make sense to me - the slow steady draw is the best way to maintain the temperature of air entering the wand on my dual digital device - the 30W or so heater struggles to keep up if the air velocity is too high.

    I was really looking forward to a new arizer solo - my xmas present to myself - it arrived 2 weeks ago but would not heat - defective so now I have to wait for the replacement but I am really looking forward to checking it out. I was really happy when I saw the thermistor and thermal paste in the heating element while stripping it down to check the battery pack but didn't realise they had a proportional integrative derivative (PID) built in - that's great news.
    vorrange likes this.
  12. luchiano

    luchiano Well-Known Member

    Messages:
    735
    Slow & long, is really the best for the most extraction, assuming you have the proper temperature set, because it allows the hot air to stay in contact with the surface of the herb much longer then if you were to inhale too much, and the airflow temperature dips, giving you a temperature that is not good for extracting thc and other cannabinoids, just flavor.

    Another thing I think is important for vaping is using a small amount of herb that has been ground very well, to the point it is evenly spread on the screen. The reason is because plant fibers are good at keeping cool. When you use more then enough to cover the screen, and it isn't ground well to be evenly distributed, the temperature of the herb under the top portion will be cooler than the top which means less extraction is being done to that portion of the herb. Stirring would ensure that every part of the herb get's heated to the proper temperature, BUT this brings another problem. If you use more then enough herb, the constant stirring will give bad flavor, and you may not extract everything if you don't stir properly, which is likely.

    Using a very small amount, prevents these issues because once you are done with extraction after the first 2-4 puffs, one stir is all that's needed to extract the rest of the thc while preventing bad flavor. You just have to keep loading fresh bowls until you are satisfied, BUT you are getting more from you herb. This is also true for smoking, but not as much of a necessity as it is for vaping.

    Having some moisture in your herb also helps keep the flavor alive, because being that the plant fibers, and water, will prevent the high heat from degrading the flavored oils or being released too much, the herb under the surface will stay much cooler then the top portion that is in direct contact with the set temperature. You will have fresh flavor with every stir or in the case of the mflb, shake. Hope that helps someone, Have fun.
    elise and vorrange like this.
  13. vorrange

    vorrange Well-Known Member

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    2,227
    Great posts, not much to add as i agree with what has been said. It correlates with my experience too, i just want to add that the Solo still drops the temp if you increase your hit velocity a bit, so it would still need to improve in that department.
  14. Hippie Dickie

    Hippie Dickie The Herbal Cube Manufacturer

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    Location:
    where the Cube rules!
    my mental image is that a slow and steady toke allows the heat to melt the waxy trichome shell, thus exposing thc to the hot air and vaporizing it.

    i set the D gain of the PID algorithm a bit high, so the temperature rises slightly with a toke.

    i don't grind ... no need to expose raw plant juice to the hot air flow ... vaporizing that stuff is not desirable. stirring is useful to redistribute the unexposed trichomes in the vial.
    vorrange likes this.
  15. vorrange

    vorrange Well-Known Member

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    2,227
    Could you explain why it isnt desirable?
  16. pakalolo

    pakalolo RoboMod v3.17 (ticking) Staff Member

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    Location:
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    The profile of the active components released varies depending on the temperature. I wrote an article about this for Vape World: Vaporizing by Temperature.

    Lots of people here have been vapourizing by temperature for a long time. There is no question that it works. The biggest problem is that a lot of people who think they know how it works—don't. As the article states, there are no binary transitions, which is the first assumption most people make when they see a chart of boiling points.
    Hippie Dickie and vorrange like this.
  17. Hippie Dickie

    Hippie Dickie The Herbal Cube Manufacturer

    Messages:
    1,905
    Location:
    where the Cube rules!
    well, for me, once the thc is gone, that's it. but i find i can still get a vapor from the abv - but what is the point of continuing? ... so i just quit the session.
    vorrange likes this.
  18. luchiano

    luchiano Well-Known Member

    Messages:
    735
    The thing is, if you have chunks of herb, even a small piece, there will still be trichomes that haven't been heated enough to release the thc. Remember air is very lite compared to the herb it is touching so the air will only be most effective to the surface of the areas it touches. If you have little chunks that haven't been broken down properly, the trichomes will get left behind creating little pockets keeping them mostly untouched due to the cooling properties of plant fibers. Also, trichomes melt into liquids so some oils will be absorbed into some plant fibers which is why just looking to see if trichomes are gone isn't a good indicator to see if you vaped the oils out of the herb.

    When we measure vaporizer temperatures we are measuring air, not the herb itself. Because herb is so light we can only measure the surface temperature, unlike meat which is so dense we can have a good idea what the temperature is inside the meat by putting a thermometer deep inside of the meat itself. We can't put a thermometer deep inside a plant cell, at least I don't know how. The goal is to have the air bring the herb to the temperature we set so we can extract what we want, so in order to make sure this happens we have to break down the plant fibers as much as we can, so they don't prevent proper temperature extraction.
  19. fubar

    fubar Ancient and opiniated inhaler

    Messages:
    91
    Location:
    Sydney, Australia
    +1.

    As the volume of vapour decreases during a session, the taste changes dramatically - losing all those delicious early spicy resiny strain specific flavours as it becomes increasingly 'smoky' tasting. That last few litres of thin sour vapour don't seem to do much for me so I don't see much point in keeping at it. I once tried combusting some to convince myself that it was useless and I was quite convinced - never tried eating ABV but I suspect I wouldn't get much out of what I leave behind.

    I'd recommend a small flashlight and a 20x glass magnifying loupe (10x works too but I prefer 20x) near your vaping station.

    Shine the flashlight into the glass bulb of the whip (you can tell what I use - but this should work for anything with clear glass in the pathway) while inhaling - sure, you can see thick clouds without the flashlight, but you'll see early and late vapour much more clearly as it passes through the flashlight beam and you can use that visual feedback to work on making it as thick and swirly as possible - eg see the effects of 'sipping' - pausing between slow small volume draws. This is especially useful for teaching new vaporists but I still do it routinely when new varieties arrive.

    Looking at the raw input through a loupe, while shining that flashlight on it before packing a bowl is very revealing. You can learn a lot about the raw material trichome abundance and fatness, and how effective the grinding or crumbling is. After no more obvious vapour is visible with the flashlight even after a long slow draw at operating temperature, repeat the process with the ABV after you knock it out - you want to see uniformly brownish toasted material with no burn marks and next to none of that shiny waxy good stuff that it started out with. If there are obvious chunks of still-greenish material and or fat shiny waxy trichomes, you probably didn't stir and recrush half way through or get all the material hot enough (eg inside big whole nugs) to vaporise all the goodness out.

    As always, YMMV.

    There's some great 'art' and personal experience distilled into this thread!

    All true and agreed - but OTOH, the acid test for me is whether the material is generating vapour I can see and taste - if there's none or little after a long slow draw with air at around 180c or so, there's probably not much good stuff left. Once you're well out on the diminishing returns side of the extraction curve, you can always eat it or extract but I doubt that I'm tossing much useful material away - like I said, I've tried smoking it on an empty head and got nothing more than a headache for my trouble - but YMMV because of all the variations in equipment, plant material and technique.

    mod note: Please do not post back-to-back. We have an Edit feature, use it. 2 posts merged.
  20. luchiano

    luchiano Well-Known Member

    Messages:
    735

    The taste changes due to be so volatile, and boil at a low temperature, that if you use very dry herb it will lose taste quickly from not having water to keep everything cool, and intact. I explained it earlier so I won't go into that.

    Also, the vapor gets thin because of whatever temperature you're using. If you were to vape at 300f, sure it will be thick in the beginning, but it will slowly get thing as you boiled off all the substances that release up to that 300f temperatures. It doesn't mean you boiled off everything you may want. Once you raise the temperature then the vapor will be thick again because now you are releasing other substances within their boiling range. This is why going up int temperature is important, because you may thing because you are high and the vapor is thin that you are done, but that isn't necessarily true.

    It is taste, and sometimes harshness,that prevents people from going higher, which I can understand, but if you use the methods I posted earlier as well as a little water tool kit, it should help prevent this problem.


    The reason why smoking abv won't work that great is because most of the thc will oxidize into cbn if you don't use it right away. This is because, when hot air touches the thc oil, the oxygen starts a process of degradation, and when you leave it out for a shitload of oxygen to do it's thing, the next day or later on in that day, most of your thc is now cbn, which is a lethargic type of high.

    Also, the headaches can be from the plant cellulose breaking down into dangerous compounds when heated to high temperatures, which is why I don't recommend eating abv anymore. Once the moisture is gone, problems occur with plants when you heat them up. Thankfully for us we want oils that can tolerate these high temperatures and absorb oxygen well, and helps oxygenate our body. The fibers(carbohydrates), and some flavor substances we like, on the other hand need that water.

    I am going to post the study that showed the effects of heated cellulose but I have to search for it.

    mod note: Please do not post back-to-back. We have an Edit feature, use it. 2 posts merged.
    Jill NYC and vorrange like this.
  21. fubar

    fubar Ancient and opiniated inhaler

    Messages:
    91
    Location:
    Sydney, Australia
    maybe it's a personal thing and almost certainly strain/variety/cure/storage related too - but I definitely do not get much of the buzz I like out of the last 10% or so of the vapour that can be squeezed out of a nugget.

    I've tried vaporizing (and even combusting) stored ABV on a relatively empty head (ie after 24 hours or more of no input) and I just don't seem to get much effect. It's interesting to know that some people do but I for one just don't seem to be one of them or maybe it doesn't happen so much with the sativa heavy varieties I prefer - yet another subtle variable in the fine art of vaporising.
  22. luchiano

    luchiano Well-Known Member

    Messages:
    735
    I think the reason a lot of people don't like going higher in temperature is because the thc is too strong when it is released in high amounts, which it will be when you go in temperatures 396, and up. This has been shown is studies. When thc is concentrated, it tends to be overbearing for people who aren't used to it, and if someone always vapes at temperatures below 392 this will be the case. You can prevent this by using small loads at a time, until you can handle the concentrated thc.

    Here's the cellulose study, they used cotton as the source for cellulose:
    Aromatization of cellulose by heat
    http://pubs.acs.org/doi/abs/10.1021/ja01281a005

    Here's the study showing thc release, and temperatures:https://docs.google.com/viewer?a=v&q=cache:YUAyrwW7WwIJ:www.volcanomedic.co.il/sites/default/files/files_repo/Cannabis_smoke_condensate_III.pdf &hl=en&gl=us&pid=bl&srcid=ADGEESjr7SHV_5qeYw_uQJBZzncO4ykzeullcXSzSBHx2aDI6vQkuvoa-bROBaAlZmyTmpRM88Lex8VPlVTBCsGgEQsPZZ0A8HkZm_Z1-ynJc8AvLZVB3zQQenlOGhMS6k8FC8inXC7R&sig=AHIEtbTnU-HVLSTlmn8oaytqQLxNxIGeFw

    Notice how the cbn rate goes up the higher in temperature you go, and this is because of the hot air oxidizing the thc. This is why when people use high temps, they claim to get the pain relieving effects or body high they want from smoking. I think the reason why the higher temperature released so much thc as opposed to the others, is because thc doesn't start releasing efficiently until 392f, and if you start at 230c you will get all of the thc, but that is too high for me to start with. 392f-410 is good to get that thc with only a little cbn. Also, I wonder how they loaded the bowl, being that they used a good amount(200mg) as this can effect how much get's released efficiently as I explained already.
  23. Dreamerr

    Dreamerr Always in a state of confusion and silliness♀

    Messages:
    5,353
    That is going to be some harsh hit at those temps which is why I don't do it. So if you both think that you have used up your herb sufficiently do you toss your ABV? If not what do you do with it?
  24. fubar

    fubar Ancient and opiniated inhaler

    Messages:
    91
    Location:
    Sydney, Australia
    Interesting - thanks.

    Since it's an old chemistry paper, those temps are almost certainly celsius. I didn't pay to read it all but it looks like not much going on to the cellulose at 190c - there's hardly any change in composition in the 190c row of the table. OTOH, www.doctorfire.com/wood_ign.pdf suggests that hemicellulose will start burning at 250c so the rest of the table seems to be showing what happens when combustion would have happened if their bomb wasn't filled with pure nitrogen to prevent a fire from starting.

    My reading of that page FWIW is that at the temps I tend to vape at (180c) there's probably very little change to the plant cellulose but if you go really hot you'll start getting combustion products. That makes sense to me.
  25. fubar

    fubar Ancient and opiniated inhaler

    Messages:
    91
    Location:
    Sydney, Australia
    I collect it in a little wooden box to keep my room tidy. Once it fills, I usually end up tossing it despite all my intentions of trying some abv recipes - I know for sure that it's not worth smoking but as discussed above, that doesn't mean it's lacking all medicinal qualities! I think if I ran out of fresh I'd be more strongly motivated to eat some...

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