DIY Induction Heater Builds and References

[TommyDee]

Hey thanks for the feedback @dantemaniaco . I do see the spare pocket as an 'opportunity zone' for Arduino or such. Not that I'm going to change this one further, I have 3 more that need completion.

Jeff can do this if he could come up to breathe. And he's got his own agenda... but I did once suggest replacing the 18650's with 18350's for a 'day pack'. Fluxer has the tightest pack in electronics along with Apollo. They can compact this even further. I fully anticipate an eventual pocketable device. Nothing is keeping it from happening except investment. Let's see what DynaTech comes up with. They've promised a battery device in the next few months [probably 6 by my guess].

These efforts are for inspiration. Eyes are on these things and the advantage is real for sure. The last thing I want to do is go into production.

 

[vapormachina]

Let's see what DynaTech comes up with. They've promised a battery device in the next few months [probably 6 by my guess].

These efforts are for inspiration. Eyes are on these things and the advantage is real for sure. The last thing I want to do is go into production.

Yes, I contacted them a long time ago, before COVID, and they had plans to launch a battery-powered Dynatech before 420, I suppose with the end of the world that we have lived these months those plans were truncated.

The problem is that now after seeing what you have done, an Apollo knows me a little, I want THIS you have made. An Apollo to have at home is something that I can build by myself with a 5€ Chinese module and a little of my time, but this that you have done for me does represent a differential value and something that not everyone can do, like the Fluxer Deluxe for example

Anyway it seems that good times are coming for vapcap lovers and I like that

 

[TommyDee]

Now that I have a DD IH sorted, it looks like I will be able to do some real power usage data. Armed with a nice little diagnostic converter I can charge the 3S 18350 pack in under an hour and get a power usage rating.

Yesterday was a fairly light day. It totaled 6.75 watt/hours of usage. I want to weight these number against Alpine 2020 usage in the same way. As a reference, the 3S 18350 1200mah is a realistic 12 watt/hours. A 700mah pack would be about 7.5 watt/hours. This tells me that the 18350 would be sufficient for a day out and about even with the lower tech at 700mah cells [read-much cheaper].

So there is my current quandary; how do you classify users for devices? Movies have ratings; devices have age requirements; so how do I classify your usage profile in order to tell you a product is for you or it is for a different type of user? How would you classify my usage? I'd say my profile would include medical home use primarily; clinically I would be considered a heavy user [oz/mo]; not session centric; dark ABV sought in a convenient medium to large load. There, I've presented maybe 6 categories that would be very helpful to understand percentages of users in these categories when defining products.

With regard to IH, I am very much looking forward to the first offer for a true pocketable IH for on-the-go day use. Something rugged and safe to share a musty space with keys and change. It's going to have the bulk of an overstuffed billfold, or course, but knowing how to size the power plant for such a device is highly dependent on usage profiles. Would you get lazy enough and use it as just an on-the-go IH full time? Would that have you searching for a bigger pack upgrade or would you go for the next size up, and just add to the collection?

We've been introduced to IH. Barely even cracked the door and already we can't get them soon enough. But I am talking the next level. This requires a little market research. And since we have a captive audience, why not give this a moment's thought on your next sesh. ...and verbalize your thoughts of course. TYIA

People are listening - share your thoughts.

 

[scy123]

Edit: sorry, gonna have to edit this idea out. Maybe sharing this is not a great idea in case I wanna use it in the future. I don't mind sharing ideas, but if it might be possible I would want to use it in the future and someone might read about it and use it first is not something I want.

Or even worst care scenario, when people make it seem like they came up with the idea. Looking at you guys, down talking my idea and than touting it like you came up with it

This is an actual real FC experience, I present my idea and than they down talk it and I spend weeks if not months defending it and than they end up using it and tout it and making it seem like they came up with it. (same people downtalking and than touting it btw)

I don't mind people talking about or touting ideas I made, but having to spend weeks going back and forth with someone on how great an idea it is and than having them using and touting it is . They can't even stop using my idea cause of how great it is, not using it would mean stepping down from the top of the ladder to the bottom

This might seem off topic and should be removed, but it's actually a warning and should not be removed.

Sorry, carry a long guys.

 

[vapormachina]

I usually vape more than 20 sessions a day, mainly with cbd but also with other herbs and ratios, on weekends or if I'm with people even more. I think the 18350s are probably the most balanced option for a pocket device, obviously the Fluxer's 18650s are fine (I'll check when I get to the end of the waiting list) but maybe it's overkill, for a day of use I think the 18350 offer the best standards in terms of size-performance; If I go for the weekend or need extra autonomy, I wouldn't mind bringing a set of spare batteries.

The capacity of the Lipo batteries or the one that offer other IHs such as the Alpine or anything that is below 1000mah seems too little

 

[Timberhead]

@scy123 I tried that configuration on a couple of builds last year. Those batteries worked pretty well. The boost board is what really turned me off. I just don't want to add that many failure points to any build.

And I'm certain that many other builders/tinkerers have tried the larger batteries as well.

 

[scy123]

You probably mean on the post I edit out. shhhhhhhhhhhh

Edit: oh you are talking about it on purpose now, bastard lol.

 

[TommyDee]

@Timberhead - The thing that makes mods what they are is targeted power management with closed loop or other sensor algo's. This is the right way to go for a portable IH product. Today's power tech can do this with ease. Considering the IH only needs to draw ~7 amps in a regulated configuration, you can do a 3X boost and still be at ~20 amps on the draw. That's peanuts for today's tech and cells. Even the bulk of such devices is easily 30% of the equivalent power plant in a minimalist design.

There is no reason a single 18650 cell cannot give you a pocket heater. Who wants to build the MOD? I don't want to get into mod'n mods but that is where the solution lies.

@scy123 - I hope you are not referring to me and the LB. PM me if it is. Your statement would be highly incorrect.

And by all means people. There is such a thing as an intellectual property rights and it is up to individuals to protect their rights. There are a number of ways to do that but silence is the best policy. Also be sure not to share company trade secrets you know are protected. The liability will remain on you if you break these trusts. Share what you wish to freely share. It is a fine balance in sharing to get further input and sharing just to be sharing. I fall in both categories. I genuinely want to learn and put hands on these projects. There is no financial reward in it for me because quite frankly, I can't stand to deal with the lot of you when it comes to money. Never let money come between friends is a huge issue even in these settings. So honestly people, I DON'T WANT YOUR MONEY! There - sed! Do you want some input on a project - any day; every day. Do you want it kept quiet? PM me. I have been bound by NDA's and know how to honor them.

I encourage everyone to develop their ideas, share their ideas, and have a community refine ideas. I've done this in so many groups in the past that I know it works. And I also know industry watches. They have been combing forums for ideas since the dawn of the internet. If you really think you have a $1M idea that you have every intention to pursue, don't post it here for G_d's sake! Spend the budget needed to research your product to make your $1M idea a reality instead.

Then again, forums are free social advertising. What really gives life to a forum is all the makers. People who grow with everyone. People who share ideas and let others help develop those ideas. At times people will break away with a product and the group supports the effort and the artisan is rewarded in a small way. Not everyone has tools - not everyone has skills - not everyone has a budget. Yet, as a community, shouldn't we all share what we've all put our souls into? At least to some level everyone should feel a reward of some kind in helping others. I can never repay my debt to all the good people here! And if you think about it, many of you can't either. So give what you can. Then you are part of a real community. Damn the outsiders.

 

[scy123]

The mod idea was a separate idea, I seen people talking about power methods with boosting the voltage and mentioned that you can just use a mod. Mods already have boosting capabilities and are as solid as they come. Never had a single mod break down on me yet and I've had a lot of mods. Not to mention you would have full power control.

You tried down talking that idea too.......

 

[TommyDee]

Sorry but no, it is the solution. I know that. MODs -are- converters. It just wasn't the right place to get into it because that is Mr_C's thread. I said there that MODs need two functions - 1) Remove the timer and 2) remove the coil sense for voltage mode. That simple but canned MODs can't be Mod'd, right? They are the cheap units so next best thing, hack a 100 watt MOD to work manually. The converter is there, the cell is there, and the brains are in the way.

The bottom line - what is the least you can get a programmable MOD for say 80 watts, which is sufficient. Is there a popular hack out there already that will take you to straight boost mode, 20 amps in and 7 amps out [wattage mode] from the cell? We can tweak the preferred voltage a little but having it just do what it is suppose to do, convert DC power, then it is done, yes.

If you take a look at the signal out of the MOD, the only thing to watch for is drop-outs below the minimum gate voltage. That can upset the IH. But the IH will work fine with modulated power without extra heat. This is why I endorse this method for making -small-.

 

[scy123]

I was replying to you directly when you mentioned ways of using buck/boost converters to make it adjustable, I see the rules are ones sided now. Also, it was only a small mention of hey you can maybe use this too. The thread creator was already talking about power options at that point and posting about a couple of solutions.

You can get a Tesla Touch for $35 and it would be able to output up to 12v in 0.1v increments. Of course firmware hack would be necessary, I didn't say it was an easy solution, just that it was an idea.

I would just say, seeing people mentioning different power options and then try to brush off your ideas as off topic was funny.

 

[TommyDee]

I apologize if that is how it came off. I am certain I invited you to come have this discussion -elsewhere-. If it was a near finished solution, of course it is worth discussing in the Fluxer thread. But I've asked for this since day one on FC it seems and have had very little response pointing to actual solutions. I have limited experience with canned MODs and none with open MODs. Last I checked, the programmable board starts at $75. That was not the topic. The topic was 'budget'. And it has to be buildable. So yes, how do we hack it for under $50? Now I know my electronics well enough that I can build or buy a heck of a compact converter. That is a MOD is with a programmable chip. I can add Arduino no problem. But people cannot go buy these things and make them work. That too was the topic of discussion. The problem was that I really did and do want to have this discussion. There ain't no magic here. It is all about how to make a MOD work as a simple voltage converter without interruption.

Bottom line @scy123 - I heard mods coming and it kept me from replying as I'd liked to have because it would go off-topic in only a few posts. Anyone else was open to pick up on the discussion. I left my top 2 issues for you to consider as I started this off. Help -us- get past this and you have all the rights to claim a solution. We don't have one yet. And here, the floor is yours. Happy to participate.

 

[scy123]

The topic was 'budget'. And it has to be buildable.

I never remembered anything about budget being mentioned. A mod power source is already built, it just has to be programmed. You can get away with $35 mods if you can program it. I agree I don't really want to get into it, but If I wanted I could probably do it in a week maybe and than anyone could plug into usb and it will take them a couple of seconds. Just because I don't want to do it does not mean it can't be done and I can't set off an idea for someone who would want it done.

 

[TommyDee]

Now you've this the real conundrum @scy123 ; Getting people interested in this shit. I am interested just by its nature. I know this is what it will take to make the next generation pocket IH's. But the coders are bored by this and the builders aren't into the art from what I can tell. You are the only active MOD geek that I know. That is a complement BTW. I am here to talk through the challenge. I already looked inside my 50 watt unit and hardwiring the power board would be pretty simple. 50 watts is not enough though. However, a 50 watt board is smaller than an 18500 2D footprint.

There is two places this part of the IH discussion can go. Connect to the MOD or Integrate the MOD's EE in a unified case for portability. Don't forget about the required bulk of the IH itself still. That will be a little bigger than the tank.

And as to budget, yes, my idea of a 3D printed shoe for the battery pack was nixed on cost by Jeff. I understood. Still a nice little upgrade in my book.

Oh, crap, I did order this one -edit- Boost/buck for 2S and full regulation.

Back to the IH itself - coil specifically
This is good shit!

What is DCR in Inductors and how does it affect your circuit design

In this tutorial we will learn more about DCR and how it affects the performance of a circuit. We will also learn how to measure the DCR value of an inductor and how to reduce DCR value of an inductor during its construction.

circuitdigest.com

 

[scy123]

Now you've this the real conundrum @scy123 ; Getting people interested in this shit.

I wasn't even trying to push it. I just said I was mentioning it and was brushed off for no really good reason and it was funny.

This is what a mod chip would look like btw. Way more than half the size.

 

[TommyDee]

That is why I think it can replace 2 18650's.

The few I've seen are limited to like 9 volts. Does this have a sustained voltage output and what is the limit? Does it natively check for a coil in voltage mode?
We are looking for an equivalent of about 70 watts out at the highest voltage possible up to 12 volts. I can tune hardware to match it. Prefer a single cell input, obviously. So the input should work down to 3V for when the unit is firing.

Programming I can do. Are we talking kernel level or user control level? Safety protocols are normally buried in the core code without easy access. If you can turn off the timer at a user level from existing code, or crank it up to say 20 seconds, then we've got a pretty decent contender for the spec.

 

[scy123]

In voltage mode the mod will put out a straight 12v no matter what is happening. Mods go up to 12v and 300w max.

Really, I don't think you would be firing IH for longer than 10s. You can find any mod that will do variable voltage up to 12v and it will be fine.

I just mentioned custom firmware cause it seemed like you like to mention timeout limits.

 

[vapormachina]

With a last generation DNA electronics, couldn't you customize the firing time and even the curve?

 

[RustyOldNail]

With a last generation DNA electronics, couldn't you customize the firing time and even the curve?

On my Lost Vape Mirage DNA75C, I can set the firing time to 20 seconds, max.

 

[scy123]

Arctic fox has a new autofire function. You can set timeout up to 60s and it will autofire for the full 60s or when you press the button again. I haven't looked into Arctic fox as none of the supported mods interested me, but I imagine you can modify it for other purposes.

 

[TommyDee]

Cool - so timeout is less of a concern. Do you think AutoFire would be a good idea in an IH?

For calculations' sake, we can talk watts as the required energy for firing a vapecap. It must be DC voltage with a minimum hold up voltage of 3 volts. This requirement is to make the IH think it is 'always on' and therefore has minimal loss across the FETs because we are clamping them on -hard- meaning the gate and the source are the same voltage. If the IH sees an interruption from PWM in the power source, the IH FETs will act on it and have inevitable harmonic issues if they happened upon a catastrophic harmonic. This has to be confirmed on a scope.

As to voltage I will show finding and let you go from there. Building on needed watts, around 70-75 is sufficient for a very solid bake, makes calculations simple. Also know that in testing, 8V-11V is a range I can tune easily. Not saying the rest is outside, just saying this seems optimal for the 'standard' design as used with our vapecaps. This gives a range of 8V*9A=72W or 11V*6.5A=71.5W based on an input source that provides say 3V at cutoff (2.5V is dropdead) while firing. But the peak is 4.2V which cannot be maintained while firing. We can therefore run a cell capability range of putting out say 80W if the driver is efficient enough. I'm using roughly 90% efficiency at 72W in this example. Therefore, 27A at 3V and 20A at 4V. This is not scary in the least in this day. Making reliable connections is a notable concern. Weld-tabs and permanence is a manufacturer's safety valve. I can see performance issues if this is poorly implemented. Or maybe 2S is open and things get easier. Now we have 6V at 13.3A to 8V at 10A. Now we're in utility territory on current levels.

Bottom line, the requirements are based on a reasonable parameters. With proper regulation, a portable IH can not only be used as pocketable device, it would also have consistent performance throughout the useful cell life.Speaking of which, yes, I have kept this in mind in this open letter to all developers. I know some of you are simply reading and not participating and that is alright. These are just numbers and math that my C'19 DIY have been gathering. You can change the numbers and plug them in for your purposes, of course. However, I feel confident these consideration incorporate what I've come to know and understand using a VC in a variety of IH configurations. So I will leave this discussion with the justification on power. We can get honest 3,000mah cells in IMR or similar that can do 30 amps I'm pretty sure. I also know that 1,000mah is a pretty good pack to load on the go. Do I need to do that math? Okay - 1,000mah 3S = 1AH*11.1V=11.1WH | 3AH*3.7V=11.1WH Get my drift? And yes, a 2S w/ regulation can super-tune any IH to perfection throughout the battery's life. Those cells only need to be capable of 15 amps. This is a big choice when deciding on a product portfolio.

The whole idea behind using a MOD to do voltage conversion is stability. A new feature for battery powered IH. There is opportunity for scaling although it should be obvious by the dissertation with regard to current levels that will be introduced. Further details can be flushed out by engineering.

 

[scy123]

I was mentioning the 21700 cells are being more developed now. You can get one that has 15wh and 30-40a. So a single one of those would take up less space and have more capacity/current draw. Probably a better idea than using a mod, I just mentioned mods cause I think it's cool.

 

[RustyOldNail]

I was mentioning the 21700 cells are being more developed now. You can get one that has 15wh and 30-40a. So a single one of those would take up less space and have more capacity/current draw. Probably a better idea than using a mod, I just mentioned mods cause I think it's cool.

I use 5 of these in rotation in the mod I mentioned above, using with a ModPod.

FROM BATTERY MOUCH REVIEW:

4-12-2018: 21700 VapCell/Samsung 40T Review by “Battery Mooch”

Bottom Line:
The Vapcell is identical in appearance and even a touch better in performance to the Samsung 40T’s I tested four months ago. Perhaps they tweaked the chemistry of the 40T since my test of it or the samples I tested then were a lower grade.

The Samsung 40T, and this rewrap of it, are incredible performers. They easily hit harder than any other cell available to us except the Samsung 30T and are a great choice at higher power levels. This cell and the 40T easily outperform the Sanyo NCR20700A for both regulated and unregulated devices.

While the hard hitting 30T is the king for unregulated devices the 40T and this cell beat out the 30T for high power regulated devices, delivering 8.1Wh at 30A down to 3.2V (about 3.6V when put in a charger) versus about 7.3Wh for the Samsung 30T. The Sanyo NCR20700A only delivered about 5.1Wh.

I am rating this Vapcell at 30A and 3900mAh. Its “typical” or “nominal” capacity is about 4000mAh.

 

[TommyDee]

MODs are cool because they are done. Maybe not the packaging, but the board itself.

And yes, larger power plants are also part of the option list driving developers crazy. I use some 5000mah monsters for gopher chasers. At 21mm diameter, these 21700's are compatible with the assumed formfactor of a 20mm coil. So yes, no reason that 21700 wouldn't work well for a starting point. It should yield equivalent output close to a 2S 18650. Those are Molicel, INR chemistry.

Therefore the second part of the search is finding a MOD that is within a reasonable budget and form-factor that meets the specs noted above. What is the $35 chip that may be a viable candidate? Will it do 1S to 27A conversion to around 10.5 volts and 72 watts? I'll assume it will do 2S with ease. at 20 seconds, I'll buy that as sufficient if a spec has to be put on it. And yes, I know for thermal considerations, duty cycle is a protective measure.

@RustyOldNail - MOLICEL/NPE INR21700-P42A 45A 4200MAH FLAT TOP 21700 BATTERY <- search that.

 

[vapormachina]

I like the idea of a single 21700. For a pocket device the option of having to replace a single battery unit instead of three for when you have to do it on the go is interesting.