It's hard to believe I've had my Firefly 2 for a couple of months already. Time went by in a haze. I've been reading this forum and benefiting from all the information and experiences that people have shared. It's cool that there are so many passionate Firefly 2 users out there who are willing to share their knowledge with the community! Thank you.
I'm very happy with my purchase of the Firefly 2. It's become my go-to vaporizer. I use it for dry herb. There's so much I like about it, I'm not going to make a list. The only negative worth mentioning from my point of view is that the battery meter is inaccurate. I did an experiment recently and found that I get approximately 18.5 minutes of total activation time on a full battery, so there's nothing wrong with my battery life. This is just the well-known battery meter issue that others have reported. FYI - my test was done on an empty bowl with the device set to Medium@100% (firmware v1.9), and I'd be happy to share more on the battery meter readings if anyone's interested.
Since I've honed my approach with the help of this forum, I thought I'd pay it forward by sharing the technique I've settled on. I experimented with just about every approach discussed here before settling on what works best for me. Most of the credit for what I've learned goes back to the good people on this forum!
Packing the bowl:
Fill the bowl with medium to coarsely-ground herb while leaving a bit of room at the top, and then place one of the metal concentrate pads on top of the bowl. Don't press down hard on the concentrate pad. When the lid of the Firefly 2 is put back on, the pad should rest comfortably beneath the lid. If the lid is pressing down on the pad, you've got too much material in the bowl. Combustion occurred for me a couple of times while using this approach, and the temperature wasn't even set to High! That was until I realized how important the last part is: make sure there's no pressure applied to the top of the concentrate pad when the lid is put on. If you do this correctly and avoid very high temperature settings, you should be safe from combustion.
Draw technique:
Activate the Firefly 2 and wait for the solid green light. Begin your draw very slowly and steadily. Continue your steady draw for as long as possible - until the 30 second auto-shutoff, if you're able to! Much has been said about the importance of long slow draws, and not drawing with too much force. I agree, but I've also found that there's an optimal range of forcefulness with which to draw. Increasing draw speed past this range is counterproductive, but reducing draw speed below the range isn't great either: it will result in slower extraction than what the Firefly 2 is capable of. As I work my way toward cashing out a bowl, I gradually increase the forcefulness of my draws. If you're in a silent room and you hear no sound from the device as you draw, you can pull harder. If you hear a subtle whistling sound as you draw, you're good. If you're towards the end of a bowl you can pull a bit harder still, just until the whistling sound turns into a pitch that sounds like a tiny motor (I don't know if that's a fitting description of the sound, but there's definitely a distinct point where if I increase my draw strength just a tiny bit the whistling sound suddenly changes). If herbs are being pulled out of the bowl when you inhale, you're pulling too hard. Placing the concentrate pad on top increases the amount of force needed to pull material from the bowl, allowing you to safely draw a bit harder than you would be able to without the pad. By the way: the importance of material staying in the bowl during use is the reason why a fine grind isn't ideal for this vaporizer.
Stirring:
When vapor production tapers off, remove the lid and stir the contents of the bowl. Try to stir the less charred material down to the bottom of the bowl, and bring the more charred material up to the top. I'm usually able to finish off a full bowl with just 1 or 2 stirs, getting plenty of good tokes in between the stirs. Before I began using the concentrate pad, I used to have to stir more frequently to keep the vapor flowing.
Temperature settings:
I prefer Medium@100% because I like the taste of the vapor at that level. At first I wished the Firefly 2 had a way to boost the temperature sans-app, but now I don't mind. If I'm in the mood for more rapid medication I do a double-toke: activate it again immediately after the 30 second shutoff and continue to draw steadily for an additional 30 seconds. I've never done a double-toke without blowing a big cloud and immediately feeling the effects.
Pour in your herb to just below the rim, no tamping, and place the ceramic screen on top and your good to go! Draw resistance is much lower and similar to using concentrates. Draw technique can be applied more loosely and still get good results...and the results are a big cloud on the first draw and no stirring!!! It also helps keep plant material out of your reclaim because you don't have to finger stir and material can't get sucked out of the bowl. I assume it will work well with a dense pack too but I hate the draw resistance so I don't care to find out. Someone else can test that.
