I'd like to jump straight to the electronics...

[DarkStar851]

I'm thinking of a design to improve the electronics in a device like the Milaana, with a contained LiPo pack instead of 18650s, and a regulator for the coil. But I'm not sure where to start. Does anyone sell a heating element that could be used for a ground-up design?

I feel like just buying an older/broken vaporizer (like a Milaana, or one of the older Firewoods) and using it for the housing and heater would be an easier route. Would appreciate any suggestions!

 

[Hippie Dickie]

not sure what you mean by "regulator for the coil" ... i use a MOSFET controlled by a microprocessor to do temperature control in my vape design.

i make a LiPo (actually, LiFePO4) pack with two 26650 cells, on a cable - i keep the batteries away from my face.

link to thread with details (a LOT of details) in my signature.

 

[ZC]

Milaana uses a SS mesh feathered around a piece of mica, not really a coil.

You could use an okr chip to add regulation. Lots of documentation on those from the ecig scene.

As for "off the shelf" heaters, there doesn't seem to be much, but you might find a cartridge heater that works for you.

 

[DarkStar851]

Milaana uses a SS mesh feathered around a piece of mica, not really a coil.

You could use an okr chip to add regulation. Lots of documentation on those from the ecig scene.

As for "off the shelf" heaters, there doesn't seem to be much, but you might find a cartridge heater that works for you.

Heh, I actually developed one of the first OKR breakout boards in the ecig community. It's a nice option but I'm not crazy about requiring a 2S configuration.

Thanks for the info about the heater though. I guess that's not the best option then. I'll work on a design and figure out my electrical constraints.

The GE NSR020A0X43Z is my target platform if I have to use a 2S supply. Shouldn't be unreasonably large if I use a LiPo pack.

not sure what you mean by "regulator for the coil" ... i use a MOSFET controlled by a microprocessor to do temperature control in my vape design.

i make a LiPo (actually, LiFePO4) pack with two 26650 cells, on a cable - i keep the batteries away from my face.

link to thread with details (a LOT of details) in my signature.

It was my intention to avoid anything with a low switching frequency (the buzzing drives me insane), so I was thinking of using a 12-20A DC-DC SMPS to regulate voltage to the heater. It'd allow an adjustable experience, so while it'd still be on-demand without temperature control, you'd have control over the intensity of the heater.

It also enables UVLO assuming I find a regulator that matches the characteristics closely enough. The Naos Raptor series has a "hiccup" protection that kicks in when the input voltage is too low to sustain the desired output current.

 

[virtualpurple]

Heh, I actually developed one of the first OKR breakout boards in the ecig community. It's a nice option but I'm not crazy about requiring a 2S configuration.

Thanks for the info about the heater though. I guess that's not the best option then. I'll work on a design and figure out my electrical constraints.

The GE NSR020A0X43Z is my target platform if I have to use a 2S supply. Shouldn't be unreasonably large if I use a LiPo pack.



It was my intention to avoid anything with a low switching frequency (the buzzing drives me insane), so I was thinking of using a 12-20A DC-DC SMPS to regulate voltage to the heater. It'd allow an adjustable experience, so while it'd still be on-demand without temperature control, you'd have control over the intensity of the heater.

It also enables UVLO assuming I find a regulator that matches the characteristics closely enough. The Naos Raptor series has a "hiccup" protection that kicks in when the input voltage is too low to sustain the desired output current.

Have you had any progress on this front? I don't understand a word of what you guys are talking about but I am definitely interested in the end results!

 

[whammy_time]

Posting just to say "Hi" to other tinkerers I've found. Like @Hippie Dickie I'm also using a mosfet and microcontroller (arduino in my case) to pwm my halogen bulb heater. I don't really follow the OKR and "2S configuration" stuff, but with a thermistor and a PID arduino library, I can control temps reasonably well (still having challenges as I'm just starting to fiddle).

It's a pretty low cost route. I used a ~$6 thermistor, had the arduino (though a nano clone on eBay is ~$5), and the irlb8721 mosfet I'm using can be had for ~$2. I've also built circuits with the atmega328p (arduino chip) on a PCB prototype board by itself, which is quite small if you want to insert your own "brains" into something else...

I haven't seen much for off the shelf heaters other than e-cig stuff. You've likely seen the Bulli and "Project" threads from @Pipes which are amazing. While those use an e-cig pack, I don't see why one couldn't just attach the wire of choice between any sort of terminals and connect to an equivalent battery or power supply and regulate with an arduino instead. I'd like to try this as my understanding of those box mods is they assume a certain power vs. resistance vs. temperature relationship and so you input these various coefficients based on your wire, resistance, an desired output... but they don't appear to monitor actual temps. I'd rather read the true temp and then tell the coil how to fire based on that. Then you don't need to care about whether it's SS, nichrome, nickel, kanthal, or Ti.

Sorry if you knew all of this stuff, just wanted to chime in with what occurred to me!