Edward's Popper Roasting Tips

Click here to contribute a tip! Go straight to the comments!

Roasting With Poppers Tips

  1. Intro
  2. Getting Started
  3. Troubleshooting the Get Acquainted Roast
  4. QuickTips for Slowing a Roast
  5. Quick Roast Technique
  6. Techniques
  7. General Notes
  8. Common Mistakes/Misconceptions
  9. Common Questions
  10. Experimental Data

Click here to contribute a tip!
  1. Intro
    This web page is intended to help people using air poppers as coffee roasters through the learning curve. A lot of us that are roasting with air poppers have had to learn a lot by trial-and-error. This site will hopefully make it possible for folks to get great roasts with less experimentation.

    The site covers both questions I had when I started roasting and the results of some experiments that I did in the search for techniques with unmodified poppers that would allow me to get roasts that rival those that have invested a lot of time and money in modifying their poppers.

    There is nothing wrong with modifying poppers, and it is clearly a rewarding hobby for some. But modifying poppers is not necessary to get excellent roasts that rival those created by any method.

    Unless you really like tinkering, there is no need to modify your popper to get great roasts. Once you have evaluated your popper with the techniques described on this page, you can then use the techniques described here to adjust the roast 'profile'.

  1. Getting Started
    I have noticed a lot of questions (I had them myself) from beginning roasters about whether their popper is getting hot enough or is getting too hot and whether their roasts are taking too long. Oftentimes, people are giving up on their poppers or popper roasting too soon. There are a few techniques that I strongly recommend any air popper to apply to evaluate their popper -- which well then help you decide which of the techniques discussed on this site to apply. The techniques are as simple as tilting the popper, stirring the beans and using an extension cord (or not).

    When you first get started it is very important to learn a couple of things about your popper. The way to learn about your popper is to do a get acquainted roast with your popper in which you give yourself permission to overroast (even burn) your beans. Doing one such roast will tell you a lot about your popper. Below are guidelines for this get acquainted roast.

    An important thing to know is that every popper (even among instances of the same model) will have slightly different characteristics. There are variations between poppers of the same model at manufacture time, and, over time, any popper's characteristics will change since the bi-metallic thermostat is likely to drift over time and the fan can wear out. So, even if you have read that a Toastmaster takes X number of minutes to roast 1/2 cup of beans, you should take the information with a grain of salt -- your Toastmaster might run a bit hotter or have a more sensitive thermal cutoff -- or maybe the ambient temperature where you are located is such that is makes a difference. In any case, the get acquainted roast (or roasts) will give you information that you need to adjust your technique. Also, the actual line voltage of your electricity will make a difference which is why your Poppery II may take more or less time to roast a batch than Joe Z's Poppery.

    Click here to see movies of a few poppers in action to see how the air currents differ between a few popular models.

    IMPORTANT ! When getting acquainted with your popper DO NOT (I'll repeat this again) use an extension cord. As you will learn later, even a high-quality extension cord can significantly effect your roast.

    1. Things to Know About First and Second Crack
      Before performing the get acquainted roast, you will need to be able to distinguish first and second crack. Almost every new enthusiast ends up wondering (after their first roast) how do you distinguish between first and second crack and what counts as the first and second cracks.

      One point is that first crack (or first pop) and second crack (or second pop) refer to periods during the roast and not the crack/pop of the first and second beans that crack/pop. The sounds of the first crack stage tend to sound (it can vary a bit with different beans) like popcorn popping. The sounds of the second crack tend to be more like the pop of rice krispies in milk -- it is a softer sound than that of the first crack.

      Ideally, there should be a distinct break between the first and second crack stages of the roast. If a popper runs hot (or if too many beans have been loaded), the first crack may run straight into the second crack. While it is possible to get a nice roast with such rapid development, most roasters agree that the results will be improved if the two stages can be made distinct. Techniques will be described later about how to do this. The goal of the get acquainted roast is to find out the natural roast 'profile' of your popper.

      Each of the crack stages will be preceded by a few outlier cracks and pops. Most of us consider the first or second crack stage to have started when there are no more than two or three seconds between cracks/pops. As the stage ends, there will be a longer and longer pause between the sounds. The stage has ended when there are more than a few seconds between cracks and pops.

      Different varieties and batches of beans may have different contours and ramps to the crack sounds. So, it can be useful to log both the first and last outliers as well as when the main crack starts. I do it by putting the outliers in parenthesis. For example, for first crack I might write the following in my log:

      First crack (3:15) 3:40 - 4:55 (5:20)

      This indicates that the very first crack sound was heard at 3 minutes 15 seconds. The stage really got going at 3 minutes 40 seconds and pretty much ended at 4 minutes 55 seconds with a few outliers sounding until 5 minutes 20 seconds.
    2. Logging
      It is very important when getting started to log your roasts. The details to log are simple but essential to adjusting your technique -- and for determining of your popper is 'up to spec'. It is amazing how many details of the roast we either forget the next day or mis-judge in the first place. Don't rely on your sense of time to judge when first and second crack happened. Use a watch, clock or stopwatch. I mention this because I have seen beginners ask for help because second crack never happened only to find out that what they thought was too long a time to wait was completely normal.

      Until you really get the hang of roasting, lot the following information for every roast. And, if you write to someone to ask for help or advice, include the information from your log.

      1. Log Essentials
        At the very least log the following information:
        Bean variety
        Ambient temperature (rough estimate is fine)
        Amount of beans put in the popper
        Popper brand and model
        Time to first crack
        Time to second crack
        Total roast time

      2. Optional Log Details
        The following information has proven to be very helpful to me, but is not absolutely essential:
        Degree of roast desired (I label this Goal on my log)
        Degree of roast attained (I label this Result on my log)
        End of first crack (not essential but can prove useful as you refine your understanding and technique)
        End of second crack (not essential but can prove useful as you refine your understanding and technique)
        Cooling method
        Notes (to note any techniques you used or observations about the roast)
        Tasting notes (to be filled in when the coffee has been rested and tasted)

    3. Getting to Know Your Popper
      If you are reading this then you probably have already roasted (or tried to roast) some coffee. It is assumed that you have everything that you need to roast and cool down your roast. The coffee created by this roast will probably be damned good BUT (and this is very important) you need to give yourself permission to burn this roast. Even if you prefer lightly roasted coffee, you will not get a good feel for how a roast develops unless you experience a roast that goes through second crack at least once. Many beginning roasters underroast their coffee because they have not gone through all of the stages of a roast and don't realize that not only are they not approaching second crack -- they are barely getting to first crack.

      You may burn this roast. That is okay. The information you gather will be invaluable and will result in better roasts in the future. I promise. Don't use your most prized and expensive beans for this roast. If you follow the directions and your popper is in good working order, the roast is likely to end up darker than you would normally want.

      Preparation for the roast:

        1. Get everything for the roast together.
        2. Make sure that you have a log sheet and something to time the roast with.
        3. Make sure to carefully measure the amount of beans that you put into the popper. You can measure by either volume or weight, but be fairly precise. You are likely going to have to adjust the amount of beans that you use -- so, if you measure too roughly, you won't know how much to put the next time.
        4. Do not use an extension cord. Make sure that the popper is plugged directly into an outlet. This makes a HUGE difference.

      1. The Get Acquainted Roast
        It is time to perform the get acquainted roast. Make sure to log the start time or start your timer running within a few seconds of starting the popper.

        Reminder . You are giving yourself permission to overroast and possibly burn this batch of coffee. It is worth the dollar or two of beans. It will save you much time and money in the future.

        When you hear the first first crack outlier, log the time in parenthesis. The sound will be something like popcorn popping.
        When first crack really gets going (a few seconds between cracks and pops) log the time.
        As first crack starts to die down, log the time in parenthesis.
        [ NOTE : there is a chance that first and second crack will run together. You may not find this out until the roast is over.]
        As the first snaps of second crack start up, log the time in parenthesis. The sound will be something like the sound of rice krispies popping.

        As second crack starts going (a few seconds between snaps), log the time. Notice that the smoke will start to smell more noticeably more intense and somewhat less sweet. If second crack seems slow in coming do not give up ! Many many beginners give up thinking that second crack is just not going to happen. You need to know if it will happen at all. If twenty minutes go by and second crack has not happened, terminate the roast.
        Pay close attention to the surface of the beans.

        When the beans start to look very oily (not just a faint sheen), log the time, and dump the beans into whatever you use to cool them in. Make note of whether the second crack was still going or not.

        NOTE : If you don't mind truly burning the beans, let the roast go all the way until the beans are past oil and have started to burn. This is only useful if you are planning on doing very dark roasts in the future. If you do like very dark roasts (French Roast, for example), it is worth intentionally burning one batch so that you are exposed to the difference between dark and burned.

      2. Evaluating the Roast

        1. Did the roast develop oil?
          If the roast did not develop oil, how long was it before you gave up?
          Did second crack ever begin?
          How much total time had elapsed at the point where you gave up?

          If you gave up in less than 20 minutes, you might have given up too soon. Most poppers will get into second long before then, but a common mistake is to give up much too early.

          If oil never developed and you let the roast go at least 20 minutes, you will need to adjust the amount of beans in your popper. Using more beans (up to a point) increases the heat of the beans. I will repeat this because it seems counter-intuitive. To get the beans to a hotter temperature, you need to add more beans.

          (Note: some poppers -- my Toastmaster for example -- can get to this point in about six minutes -- less on a really hot day. On the other hand, my Wearever Pumper takes about 18 minutes to get to this point with the 'standard' amount of beans.)

        2. Did the roast get to second crack?
          If the roast did not get to second crack, did it develop an oily sheen? If so, perhaps the roast got to second crack and you didn't hear the snaps. The snaps can sometimes be hard to hear over the fan noise. Some beans also have fainter snaps then others.

          If the roast did not get to second crack AND did not develop oil, did you let the roast go at least 18 minutes? If you did not let the roast go 18 minutes, try again and let it go for at least 18 minutes. If after 20 minutes no oil developed and you did not hear any snaps then something will have to be done to increase the heat.

          Try again using 1 1/2 times as many beans as in your first trial. You may need to help the beans out with a stir or shake occasionally until the roast gets going. The beans start out dense and hard to move. Once they heat up, they will expand and lose some water weight and the air flow should move them happily around.

        3. Was there a pause between first and second crack?
          If there was not a pause between first and second crack, heat is probably going into the beans faster than they can react to it. Some people are fine with such roasts, but most people find that a few simple adjustments will result in slightly longer roasts that one can control more easily and which result in better tasting coffee.

          The biggest problem with roasts that develop so rapidly is that it is hard to stop the roast at the right time if you are aiming for a particular roast level. The reason is that the outside of the bean may be ahead of the inside of the bean. The outside of the beans might be well-done while the center is medium. If you like Full City to Vienna style roasts, they are very hard to get reliably if the roast goes too fast. Also, there are several chemical changes that happen inside the bean that don't get a chance to fully develop if the heat is pumped too rapidly into the bean. The result is a less complex set of flavors than more evenly roasted coffee.

          A few simple techniques can make a lot of difference. On my Toastmaster, simply taking the top off and stirring occasionally with a wooden spoon changed the profile just enough so that rather than having scorched beans in 4 1/2 minutes I had a lovely light Vienna roast in 6 minutes.

        4. Was the roast fairly even?
          The other thing to notice is whether the coffee seems fairly evenly roasted. If there is a wide variety of colors, check to see if you are roasting a coffee that naturally roasts unevenly. Yemeni coffee, for instance, always roasts unevenly. If you roasted a variety that is supposed to roast evenly, you will want to do something to ensure better agitation of the bean mass.

          In most cases an occasional shake or stir (with a wooden spoon) will help immensely as long as the fan works well.

          If the bean mass did not move steadily once the roast really got going, you may have used too much coffee OR the fan may not be working well.

      3. Evaluating the Results
        This section is just a rough guide to help you figure out where to go from here.

        If all of the following are not true, see the Troubleshooting section. Even if all of the following are true, you may want to read the rest of this site -- a few simple techniques can help you get the most out of your roasts.

          1. Roast took between 6 and 18 minutes
          2. There was a pause between first and second crack
          3. The beans developed a shiny oily surface

  2. Troubleshooting the Get Acquainted Roast
    If your get acquainted roast did not work out well, take a look at this section.

      1. The roast took less than 6 minutes
        This isn't necessarily a problem -- as long as the first and second crack stages were distinct. If there were distinct first crack and second crack stages, you don't necessarily need to adapt any new techniques -- especially if you like light roasts. But, most (not all) popper roasters find that the flavor of roasts develops better if the roast develops a little more slowly. See the techniques section for a number of techniques that can be used.

        If you like Vienna roasts, you will probably want to slow things down a bit. I found that it was difficult to get a true Vienna -- the color of Full City but with a very light oil sheen. I believe that the reason for this is that if the initial phase of the roast progresses too rapidly that either the surface of the bean scorches and does not let the oil out, or the fast progression of the roast prevents the oil from migrating to the surface. (Note: I find that Vienna roasts often do not develop the oil sheen until the beans have rested 24 hours or so).

        Quick Tip: reducing the amount of beans by even a small amount can extend the roast time enough to make a nice difference. As counter-intuitive as it may seem, having fewer beans (up to a point) reduces the build up of heat. In my Toastmaster, going from 1/2 cup to slightly less than 1/2 cup extended the roast times by a minute (and kept first and second crack from running into each other without a pause). If you can roast without the popper's hood on (you may want to use a tin can as a chimney to keep beans from popping out), I recommend removing the popper's hood AND stirring the beans (with a lifting motion to ensure turnover of the bean mass) every five to ten seconds until first crack gets going. Using these three techniques together, my roast time went from five minutes to eight to nine minutes with a great deal of control over the final degree of roast.

      2. The roast took more than 18 minutes
        If you succeeded in getting the beans to first crack but the beans never roasted to the point of being oily, you should try roasting again with 1 1/4 to 1 1/2 times as many beans as in the first roast. Then, evaluate the roast. It seems counter-intuitive that adding more beans will get the bean mass hotter but it does (up to a point). For example, in my ToastMaster a roast with just less than 1/2 cup of beans (about 72 grams) takes about five or six minutes to get to the oily stage (French Roast). With 100 grams of coffee, it gets to the oily stage in just over three minutes. Bean mass makes a huge difference.

      3. There was no pause between first and second crack
        If your roast (to the oily stage) took less than six minutes and there was no pause between cracks, use the slowdown techniques described in the previous item's Quick Tip and look into the techniques covered in the Techniques section.

        If your roast took longer than that, you may want to repeat the roast and listen VERY carefully. It is possible that ambient noise and the fan noise kept you from hearing the crackles that are the second crack stages sound. Some beans give very faint second crack sounds. If you are having trouble hearing the cracks, you will have to pay close attention to the smell of the smoke and the appearance of the beans to judge the degree of roast.
      4. The beans did not develop an oily surface
        If you stopped the roast before 18 or 20 minutes were up, try again.

        Did you hear the second cracks? If so, you probably just need to let the roast go a bit longer.

        If you did not hear the second cracks, see the section above about what to do if the roast takes more than 18 minutes. You will want to roast with considerably more beans. If that does not work, you probably have a defective popper.

        If you used an extension cord, you did not read the directions carefully. Read the directions carefully and repeat the roast without the extension cord. Extension cords make a huge difference.

  3. QuickTips for Slowing a Roast
    Here is a quick recipe for getting poppers under control (such as my Toastmaster) that go too fast to control the degree of roast. Try all three of these together.

    1. Roast with the hood off
      This of course means that the chaff will go all over the place. There are several advantages: you can observe the beans better, it slows the roast down ever so slightly (but enough to make a very helpful difference). You will probably want to fit the popper with a 'chimney' to keep the beans from popping out. An 8 ounce tin can that held tomato sauce was the perfect size for my popper.
    2. Tilt the popper at 30 to 45 degrees until first crack
      I suggest shaking the popper a few times (every 30 seconds or so) to ensure that the beans on the bottom and the beans on the top get mixed. I leave it tilted until end of first crack but others level it at beginning of first crack.

  4. Quick Roast Technique
    Some people really enjoy rapid roasts. In some poppers a roast can take as little as 3 minutes (sometimes less). This method is best if you don't like dark roasts since things go so fast that the outside of the beans tend to scorch. But if you like City and City+ this is a very quick way to go. This is definitely a matter of taste. Some folks swear by it -- others swear at it.

    Let the roast go just past first crack and shut the popper off
    Then dump the beans and get them cooled quickly.

    Variation: turn the popper off as first crack ends and leave the roast continue (in the turned off popper) for a minute or so and then dump the beans to cool them off.

  5. Techniques
    A number of very very simple techniques can be brought to bear on roasting with a popper. I provide a few basic combinations of techniques to try together to get started. But you can use any combination of the techniques together. What works best for you may be different than what works best for me. These suggestions are the result of a series of experiments that I did. The experimental data is found farther down the page.

    1. Adjusting the bean mass
      The roast profile will change dramatically in poppers just by changing the amount of beans in the popper. The way it works is counter-intuitive at first thought. The beans will get hotter if there are more of them (up to a point) in the popper, and they will heat up more slowly if there are fewer.
      1. To speed up your roast -> Use more beans
        If you are adventurous, you can use a lot more beans than the manufacturer recommends. You will need to experiment some to get just the right amount. Going from 72 grams to 100 grams of beans in my Toastmaster makes a HUGE difference in the speed of the roast.

        The exact impact will be different from popper to popper. So, trial and error will tell you what is best. Just log your measurements and it will be easy to get things just right.
      2. To slow down your roast -> Use fewer beans
        That's right. It seems counter-intuitive, but with fewer beans the bean mass will heat up less quickly. Just going from 72 grams to 60 grams will make a dramatic difference. If you are like me and are roasting for a family that only drinks a couple of cups a day, this is good news. The ideal amount of beans in my Toastmaster is about what we drink in four days. So, the beans are always fresh.

    2. Tilting
      Tilting the popper at a 30 to 45 degree angle has a very nice effect on the heat ramp. Lesser angles may also help the mixing of the beans in a popper like the Toastmaster that has a tendency to be spit beans out the top after first crack. Tilting slows the roast a bit and can (for some poppers) improve the mixing of the beans. The best angle will depend on your popper and the particular beans you are roasting. Watch the beans in the popper, you want an angle that results in a nice bot not too fast turnover of the beans.

      A couple of tilting variations that I use

      1. Tilt until end of first crack and then completely level the popper
      2. Tilt at 30 - 45 degrees during the first part of the roast and 10 to 15 degrees after first crack . I do this in my Toastmaster because the beans seem to mix better at a slight tilt than when the popper is completely level. I sometimes roast with the popper completely level anyway.

    3. Stirring
      Stirring with a wooden spoon every five to ten seconds (through beginning of first crack) can slow things down just enough that first and second crack will become distinct in a popper that tends to run them together. When you stir, use a lifting motion to carry some of the beans at the bottom higher up. Try not to impede the motion too much or you may speed up the roast.

    4. Removing the hood
      If you are roasting somewhere where it does not matter if chaff goes all over the place, take off the top. Almost everyone that roasts with the top off feels that the results have been better than with the top on. This is especially true if the roast tends to go to fast.

      Use a tin can (with the ends taken off) as a chimney to keep the beans from popping out. Make sure to listen for the difference between the sound of beans hitting the tin can and the sound of second crack.

    5. Stalling
      I have found that the occasional three to five second stall can have a beneficial effect on the roast profile. I sometimes stall for a few seconds as the roast approaches first crack and then for a few seconds midway between first and second crack.

    6. Extension cords
      Extension cords have the most dramatic impact on the roast profile. Many people that complain about their popper not getting hot enough are using extension cords and find that eliminating the extension cord fixes everything.

      For those of us that like to slow down certain stages of the roast, you can use an extension cord for part of the roast to dramatically change the roast profile. For example, my Toastmaster with the hood off(using tilting until first crack) generally gets to second crack at about seven or eight minutes. Plugging the popper into a 75 foot extension cord (a nice thick one) after first crack ended resulted in a 16 minute roast to second crack. Quite a change!

      Here are two variations to try:
      1. Use an extension cord until end (or beginning) of first crack and then plug the popper directly into the wall
      2. Plug the popper directly into the wall until the end of first crack and then use the extension cord until the beginning of second

  6. General Notes

Roast times
Roast times vary a lot from popper to popper. Even two units of the same make and model can exhibit very different roast times. The ambient temperature and the line voltage can influence things. If you get to second crack anywhere between six and eighteen minutes, you will be able to get great roasts.

I recommend doing a few experiments to see if there is a general profile that appeals to your palate. It seems like people are divided as to whether thay prefer a longer ramp from start to first crack or from first to second crack. Try it yourself. Take a look at your log and see what your first crack time is. Use the various techniques described above to move the first crack later without doing anything to influence the first crack to second crack stage. Do some roasts where you leave first crack where it is while extending the time between first and second crack.

My personal preference for my Toastmaster (with just under 1/2 cup of beans which is about 72 grams) isto get to first crack at about 4 to 5 minutes and get to second crack somewhere between 7 and 8 minutes. The times can very as much as a minute in either direction depending on the bean etc.

On my Wearever Pumper, I tend to roast more beans (from 100 to 130 grams) and get great results with first crack around 4 or 4 1/2 minutes and second crack anywhere from 9 to 14 minutes.

  1. Common Mistakes/Misconceptions
    -- COMING SOON --

  2. Common Questions
    -- COMING SOON --

  3. Experimental Data
    I bought several pounds of junk beans just to experiment with. I wanted to measure the effect of various variables on popper roasting. The experiments were done with a Toastmaster bought from Target. It is 1200 watts. The goal was to find if some simple low-tech techniques can be used to influence the roasting -- especially since the Toastmaster tends to go from 0 to burned rather quickly).

    If you are a popper roaster and just want the results and conclusion, you can skip down to them.

    The methodology:

    Popper was preheated 1 minute before each test with the top off. Unless otherwise noted, 72 grams of beans (equivalent of 1/2 cup) were put in the popper which was then turned on for four minutes. At the end of four minutes, the popper was turned off and a thermometer was held in the column of beans so that the thermometer tip was about 1/2 inch from the bottom. The popper was rested approximately 10 minutes between tests in front of a strong fan.

    There are some weaknesses to the protocol that I used. So, the temperature comparisons aren't precise but I believe that they do give a good sense of the relative influence that these techniques can have. (What were the weaknesses? Ambient temp. varied over the course of the testing but it doesn't appear to have had a big impact -- temp was 68 at start and 75 at end. I repeated a test done at 68 and the results barely differed)

    Variables explored:

    Roasting with popper's top on
    Roasting with popper's top off
    Tilting popper
    Using an extension cord (75 foot)
    Using a can to extend the popper column
    Reducing the amount of beans
    Increasing the amount of beans
    Both stirring and tilting

    Also explored: the influence of having a thermometer in the roasting chamber and the relative readings of the thermometer when the popper was still on and shortly thereafter. Also, the difference in reading of the thermometer just 'floating' in the popper column or suspended above the bottom by a clip.

    Results (temp. of beans after roasting for 4 minutes in a preheated popper):

    72 grams, top on: 360 degrees F
    72 grams, top off, tin can chimney: 365 degrees F
    72 grams, top off, no chimney 370 degrees F

    (note about the above: there were too few repetitions for these differences to be meaningful. i believe that they are accounted for by environmental variables)

    All below are top off (with chimney)
    72 grams, 75 foot extension cord, 315 degrees F
    50 grams of beans instead of 72 grams 320 degrees F
    72 grams, popper tilted almost 45 degrees (by resting lip on a bowl): 325 degrees F
    72 grams, beans stirred every 5 to 8 seconds, 340 degrees Fahrenheit
    100 grams beans 400 degrees fahrenheit

    By comparison, my WearEver Pumper (1250 watts) resulted in a bean temp of 345 (standing flat).

    Note: only the extension cord roast did not get to first crack (there were a couple of outlier beans that popped but not enough for me to call it first crack). All the other roasts were somewhere in first crack when the roast was terminated at the four minute mark.

    Notes: leaving my thermometer resting in the popper column during roasting raised the temp slightly (probably because it seemed to slow the bean movement). It had the same influence when suspended in the column so that it was not touching the bottom. In both cases, the temperature read while the hot air was blowing was considerably higher (50 to 80 degrees higher) than the temp measured when the popper was turned off. So, the temp measured when the popper is on is not an accurate measure of bean temp (in case anyone else was naive enough to think it might).

    Temperature notes: these temperatures probably do not accurately represent the peak bean temperature since it took the thermometer 45 to 90 seconds to reach its maximum reading. But the error should be fairly constant across the tests.


    1) the popper will run a bit cooler the first time it is used in a series of roasts. I have no idea how long it needs to rest to totally reset, but the difference in bean temp was 20 degrees F between the first and second tests of the day. The subsequent tests showed no appreciable difference except for those accounted for by the variables.
    2) Using a long (75 foot) extension cord had the most significant impact on lowering bean temp. Using 50 grams of beans instead of 72 was almost as effective. Tilting the popper (at about a 45 degree angle) was almost as effective. Stirring lowered bean temp but not nearly so much as the extension cord or tilting or reducing the amount of beans.
    3) There was no appreciable difference with the popper's top on or off or with my tin can chimney.
    4) Tilting and stirring combined did not reduce the temp any more than just tilting. In fact, the bean temp was slightly more than the temp when just tilting. Probably because the stirring impeded the flow momentarily.

    For those that don't want to do any wiring of their poppers (because they are lazy like me), it is clear that you can significantly influence the roast profile by: tilting the popper, using a long extension cord (you might even be able to use a shorter extension cord if it isn't a very good one -- since cheapo extension cords offer more resistance per foot), and adjusting the amount of beans.

    A couple of notes: the 100 gram roast was both hotter (and hence darker) and more uneven than the other roasts. With 100 grams in the popper, some beans were glistening with oil while others were just getting to City. Most other roasts were quite even.

    The lowest temp roasts were the most uneven but past experience (from doing real complete roasts using the techniques) tells me that is only because they had not got nearly as far and that the uneveness would disappear as the roast progresses.

    The comparative effect of these techniques should apply to any popper. So, whether you are using a Poppery, a Pumper or a Toastmaster, you can use them to slow or speed up the roast. I plan on using the techniques (tilting and extension cord) to slow down the end of my roasts in the hope of developing more complexity and depth flavor with my roasts.

    I hope that someone will find the info useful.