Hi Everyone,
Please be warned, this is going to be a long post! Have a few hits before you begin
(Part I)
I've been around for a while but don't post that often. Own many vapes not limited to BAKx, P80, TM1 (original from when it first came out), TM2, FW7, M22+V5+CUBs and many more, go VAS or go home!
Figured I'd post up my findings with BAKx tuning to help others as I've been messing with it for a bit and wanted to share. Being a nicotine vaper for over two decades I have acquired quite a few mods over the years including the infamous Predator that's been mentioned here, Gen3's, RX2/3s (worst for resistance), squonkers, etc. but not using DNA's since I moved away from drippers, temp control and building coils and sold them - wound up right back with plain old straight wattage tank vaping with an ANT chipset mod. The Predator does a decent job, but its fire response is not as fast as other mods with better chipsets.
I made this post mostly for mods that will work with TUBO or Arctic Fox but may give insight into DNA users who tinker as well
I am trying to write this with as much explanation as I can as some people here have more knowledge with mods and others are just starting to delve into the world of mods because of the BAKx. It's still hard to dumb this all down to basic concepts, but hope it helps the community. It’s mainly information for DIY types – if you have Ralph pre-configure it for you on a mod then you have no need for this information.
For reference - these are the recommended TCR values for all different types of coil metals:
Nickel DH: "0704" [0.007036]
Ni200: "0600" [0.00600] (According to Steam-Engine.org)
Ni200: "0620" [0.00620] (According to @DJLsbVapes and other various sources)
Nifethal 70 (Alloy120): "0525" [0.00525]
NiFe30 (StealthVape): "0500" [0.00500]
Tungsten: "0450" [0.00450]
Nifethal 52 (Alloy52): "0404" [0.004036]
NiFe (Reactor Wire): "0400" [0.00400]
TitaniumGrade1: "0366" [0.00366] (According to Steam-Engine.org)
TitaniumGrade1: "0350" [0.00350] (According to the SX Mini Manual, @DJLsbVapes and other various sources)
TitaniumGrade2: "0353" [0.003525]
NiFe30 (Resistherm): "0320" [0.00320]
SS410: "0155" [0.00155]
SS430: "0138" [0.00138]
Invar 36 / Nilo 36 / Pernifer 36: "0112" [0.001116]
SS304: "0102" [0.001016] (According to Steam-Engine)
SS304: "0105" [0.00105] (According to @DJLsbVapes and other various sources)
SS316L: "0088" [0.000879] (According to Steam-Engine)
SS316L: "0092" [0.00092] (According to @DJLsbVapes and other various sources)
SS316: "0088" [0.00088] (According to Steam-Engine.org)
SS316: "0092" [0.000915] (According to @DJLsbVapes and other various sources)
SS317L: "0094" [0.00094] (According to Steam-Engine.org)
SS317L: "0088" [0.00088] (According to @DJLsbVapes and other various sources)
SS317: "0088" [0.000875] (According to @DJLsbVapes)
(Credit to e-cigarette forum - Ultimate TCR Thread)
TCR is the temperature co-efficient of resistance or change in resistance of a metal over TIME. The above TCR values are "safe" TCR values and take into consideration single or dual thin wire type coils/metal wire. BAKx is a long FLAT (SS316L?) coil so the 88-92 TCR listed SS range would be too low for it. TCR is only one part of the algorithm to calculate coil temperature. A small thin metal wire (e-cig/dab coils) will heat up or stay hot quicker than the thicker flat metal used in the BAKx so the actual TCR of the BAKx coil is for sure higher than 88-92. TCR is just one factor for the algorithm to try and calculate what temperature the coil is at. There is no true temp sensing method to do this unless you use some very sophisticated type equipment. Many devices (even non-mods) use this algorithm since it's been proven to be fairly accurate +/- 1 or 2 degrees F and cheap to implement, but never 100% accurate. If you wanted 100% accuracy/temperature precision the BAKx price would rise to a thousand dollars just for the temp sensing tech, lol. Same goes for any mod based vape like the P80 or TM/Firewood (similar type algorithm is on the main board’s chipset).
The lower the TCR number is set, then the mod will think it will take less energy to get to or maintain a specific temperature in a given type of coil metal (less aggressive). It is used in combination with the PID Algo settings and of course must be close to true. To throw more values into the mix, the internal glass chamber + stem + material's water content will also effect the temp inside the chamber. When you actively draw on the stem it also cools a bit inside the chamber so the Algo PID settings need to compensate and recover to the set temp using the algorithm and the mod settings. With that said, many things effect proper chamber temperature and we can get CLOSE
The way it works is that there is a given resistance to any metal type (in ohms) when power/current is sent through it. Some metals are preferred to others (that’s a no to kanthal – this metals resistance doesn’t change enough to be measured accurately with this tech). The resistance (measurable) value rises as the metal material warms from the electrical resistance going through it in turn creating heat. The amount of that rise/change in time is how the algorithm makes a very close educated guess at what the temperature of the metal/coil is actually at. It then decides to give more power or less based on Algo settings and TCR among others to maintain or get to the set temperature. It is never 100% accurate. Throw in the fact that people are using different mods; each may have a little variation in what their mod thinks the 'cold' resistance is for the current coil being used from start (cruise) to actively heating it up over a duration of time (300s). Even though your mod may calculate the initial resistance incorrectly the rest of the algorithm is most likely sound and will work as long as the other values considered are accurate. This is why it is stated to lock the ‘cold’ resistance to a certain arbitrary number (.22 less than mod detects) and then make adjustments to locked resistance up and down .02 from there if result is either too cold or too hot. The mod needs this initial cold (room temp) resistance value as a reference point to run the algorithm calculations and correctly compare to what the resistance is ‘at this point in time' after applying power to create heat. It's constantly calculating these values as it's being fired or cruising. Since the recommended TCR is 185 (too high) nobody can really use their true or close to true locked cold resistance. Although using TCR 185 makes it easier for Ralph to troubleshoot issues, it's just a 'general' starting point and dropping .22 from the mod's calculated cold resistance and going up or down .02 from there does work but let's try to get closer to true or what you like once you understand how it is all comes together to do proper temp control. There is a lot of argument on both of these theories and no one is probably 100% correct – this is just food for thought.
Arctic Fox allows for easier customization of these values, but the latest version does seem to have a little bug with Wismec mods in that when first turned on it always likes to lock the current resistance as the cold even though you have a lower resistance locked with the pad lock symbol in AF's settings. There is a way around it by going to the Edit menu (whatever clicks you assigned) and then it picks up your original locked resistance again for that session - annoying and I don't think it's being supported anymore
I have preferred the TUBO Firmware for the BAKx and since it is based on the same original sources as Arctic Fox the changes that I'm going to explain in TUBO firmware also apply to Arctic Fox (some options are named different in some places, or located in different menu’s, but it’s all there)
Continued next post...