The "Project" DIY Herbal Vaporizer

[KeroZen]

I'll share some of my ideas too: if we can afford to take more space, then we can use longer element/coils to increase the surface area, but then the resistance would be quickly too high, limiting our power output...

...unless we have several elements wired in parallel rather than in series. The difficulty then becomes how to ensure the different elements never short (be it after a shock, during transport etc) and how to assemble them without using any solder. In the Elo they have a set of parallel vertical ceramic plates with embedded resistive wire for instance.

I imagined several arrangements and one could think that for example using the latest coil design @Pipes posted above it would be best to stack them each with the spiral perpendicular to the air flow direction. But then the heat would cumulate and I think the last spiral in the path would get overheated by the heat generated by all the previous ones, thus raising its resistance and lowering its contribution... but maybe not?

In the Elo the plates/fins are parallel to the air flow such that each element contributes equally (although those at the center should also be working harder...)

Another idea would be to use silver wire as the coil. Using the steam engine calculator I realized it would be impractical in the Project, but if we have more space, it could be possible to wrap the several meters required haha.

I have plenty of other ideas but honestly, I'm so impressed with what such a tiny coil can already achieve in the Project... is it worth it? I mean, once the hotspot issue will be solved, I'm unsure I would need anything more. This thing just rocks and is so fast! I can really get big rips with it already. I'll bring it to a music festival this evening, gotta dissipate that linseed smell!

 

[Pipes]

These ideas are great guys. Tried the twisted coils ect, and in the end, it all comes down to a watt is a watt. Wastage is the key. I did many experiments in the Bulli thread in an effort to gain the best efficiency for battery life.
In the ecig domain, surface contact is more important so don't let their techniques confuse you, that part doesn't apply to us. The wastage coming from heat up time which also means un-used or wasted power. Nothing much is gained at the cool down neither so more wasted energy. IMO, trick is to get hot enough to work and fast enough to minimise the heating surrounding surfaces.
@KeroZen is correct, we have the power but directing it is the key. Throwing more heated metal is indeed a waste of power and efficiency.

Couple things. First off my comment on it taking more power was in-correct. I was having odd drifting temperatures. Ended up the top loop of my coil was shorting while been read for resistance but would open when heated causing me some confusion in setting it up. New findings are it's the same or even more efficient power wise.
So I cranked up the heat to the brink of combustion to get a solid pattern of where the heat is coming from. Here is a pic of the ABV after 3 good tugs. And it tasted really nice.



And again after 3 more.



Very charred but still tasted OK. It does look burnt but it's not.
Here it is in my hand after.



I still put back in and got a couple more puffs.

The pictures should tell the story.

 

[Dan Morrison]

@KeroZen , wow, we must have been on the same wavelength because last night I spent a couple hours with the steam engine and came to the exact same conclusions! Ended up going to bed at around 5 am because I was getting so carried away, hahaha.

I wanted to compare the heat flux and heat capacity of the coil that @Pipes is using now, and a potential silver wire, and see how the surface area compares between the two.

I chose to do a comparison with both coils being fed 5v, 10amp, and outputting 50w. This works out to be a 0.5ohm coil. This is my guess at what the current coil design is running at. @Pipes , feel free to correct me!

Notice how I will be changing the wire gauge.

316L Coil Characteristics
Wire Gauge: 22
Wire Length: 217mm (8.5")
Heat flux at 50w: 114 mw/mm²
Heat capacity: 282.59 mJ/K
Surface area: 439.24 mm²

Pure Silver Coil Characteristics
Wire Gauge: 30
Wire Length: 1601mm (63")
Heat flux at 50w: 39 mw/mm²
Heat capacity: 199.34 mJ/K
Surface area 1282.97 mm²

So, we can see that these parameters are not far off! The Heat flux is greater with the 316L coil, so it would definitely run a hotter surface temp. But the Surface area of the silver coil is more than double... so we should be able to heat the air more efficiently with the silver coil.

Heat capacity is sorta similar, but the silver coil should heat up and cool down faster.

Lets tweak the parameters to see if we can get closer to the same characteristics of the 316L coil.

To get the same heat capacity and heat flux of the 316L coil in silver 30AWG wire, you need to ramp up the voltage to around 12V, current to 17amps, to feed a .7ohm coil with 200w.

This gives you:
Heat flux: 112 mw/mm²
Heat capacity: 279.07 mK/K
Surface Area: 1796.14 mm²

Close enough to the 316L coil now. But drawing 7 more amps, and requires higher voltage to boot.

The length of the wire is 88" as well!

Huge surface area though! I could really see this working if the wires were setup properly and packed in there... Buuuuut... 12v...17amps.. I don't think so.

Anyhow I think the silver/gold/copper wire is worth investigating.

@Pipes , I don't think i understand why surface area doesn't apply to us? I feel like the principles are the same. They want to transfer heat energy to liquid, we want to transfer heat energy to air. The more surface contact we have between coil and air, the better the heat transfer.

Or is it just that we don't need more efficient heat transfer... because it's already plenty?

Also, for wrapping a super long 30AWG silver wire, you would need some sort of support structure.

Two things come to mind... dream catcher and sock knitting machines.

of coarse the weave would have to be done in layers to avoid contact between the wires causing shorts... but I'm sure it can be done.

And there is the issue of even heating as well.. those 30awg wires might heat very unevenly...

 

[Pipes]

My theory is that 1 watt translates to X energy which in turn will be Y amount of heat. This should work out as a constant. If this is the case than the efforts to transfer the energy "evenly" without wasting it is the goal. Agreed, using a finer material will work as it covers up the open air flows better. But IMO, this is more to even out the distribution. Not necessarily surface area. Downfall is a more delicate, complex coil which will work fine. But, my belief is keeping it as simple as possibly getting away with the minimum requirements to get the desired results. ECig users are looking for direct contact with the EJuice which is where the surface area is more critical. Kind of goes hand and hand but for different reasons. We want the end result leaving the oven to be uniform which doesn't necessarily mean you need more surface area.
I have actually played with using a SS mesh for a heater. Here's a couple pics. One is using a 22mm drip atomizer and the second was a modified Kayfun Mini.

The first was a total fail as the resistance was not linear from the post to the outside. Thus, concentrated all the heat in the center.
The second was and is a good candidate to keep in mind. I stopped as never got around to figuring out how to easily secure the top potion of the mesh. I wedged it between the upper screw in cylinder which wants to cut the mesh. Lasted long enough to know the resistance was within limits of the mod output. (Barely @ .05ohm)
Also, the heat up is fairly even. Would run like a mini TC FlashVape.
This is getting really fun stuff now. We live in a great age!

 

[enjiatt]

@KeroZen @Dan Morrison

I honestly think you guys should look aT airflow patterns too.

I think about it like this (and i may be wrong) we are just heating a piece of wire that heat from the middle out. Where ever the metal is sitting shouldn't necessarily dictate where it ends up. so with the coil in coil design it isnt surprising that there is a hotspot in the middle because the coil glows hottest in the center.

An experiment I did a while ago was to take whatever chimney setup you are using and hook it up to a piece of silicone hose and get a hookah or ecig and blow this clouds through it and look at how the air patterns are.
now plug one of the intake holes and see what it does to the smoke patterns coming out.

It will make you rethink the way in intake lol. Im not saying that it is exactly how heat is carried but I think it is a good clue.

Ill eventually be making a single coil design wrapped inside of a thick piece of glass. The theory around it would be the middle hotspot is naturally there but now that glass is added there is extra heat available. but who knows these are all theories. I walk away from glass for a little bit because cutting it is a hassle.

 

[KeroZen]

I wish I could share more, but the topic of RBT's patent (Zion/Milaana) is "high surface area heater", and we all agree it compares positively to desktop vapes in terms of cloud production. Several beta testers even compared it to the Evo and many say it's like a portable LSV (or rather MFLB meets LSV)

I invite you to read this recent post, it's mostly speculation but explains what we experience in practice (esp. the bit about being able to continue drawing for a long while afer the trigger is released)

http://fuckcombustion.com/threads/zion-vaporizer.17061/page-223#post-970166

But I agree with @Pipes about the better efficiency of the Project: it was the goal during design. Whereas RBT's goal was "massive power" and giant cloudage... That being said, I was able to get some really good rips with the Project, it's really not too shabby!

Maybe we could develop a power monster version of the Project? Less efficient but nastier!

 

[jojo monkey]

Maybe we could develop a power monster version of the Project? Less efficient but nastier!

I am interested in this.

The dreaded hot spot.

Adding more surface area got rid of the spot in my much larger desktop vape. I imagine coils are a different ball of wax with the higher temps and smaller surface area. You have such a short length to do it all. I hope you guys figure it out.

 

[stickstones]

I'm only on page 6, but this thread is stoking me !

 

[enjiatt]

have any of you tried modifying the airflow so that it is more open. This would help some with the hotspot issue. But you will need to turn up the temperature.

 

[KeroZen]

Hey @OF my good man, I saw you posting in the Divine Tribe attys thread, so I *had* to summon you here, as you don't want to miss that train sir!

This vape already rocks but your experience could prove much helpful to keep improving it! So by attracting you here I'm doing some kind of online distributed brain drain if you will...

@Pipes : wow that's not even a hot spot anymore, it's a black hole bowl!

 

[OF]

Hey @OF my good man, I saw you posting in the Divine Tribe attys thread, so I *had* to summon you here, as you don't want to miss that train sir!

This vape already rocks but your experience could prove much helpful to keep improving it! So by attracting you here I'm doing some kind of online distributed brain drain if you will...

@Pipes : wow that's not even a hot spot anymore, it's a black hole bowl!

Thanks for the 'heads up', but I'm currently 'mired down' about half way through the earlier thread (up to January something), so I'm lagging way back. But I've got a pretty full plate right now and need (or rather want......) to clear some of them away before taking on new projects.

Much as I'd like to do otherwise of course, who doesn't like new toys? But last time it got crazy out of hand and the results were not that good. As soon as I've done as much damage as possible to a couple of things this guy comes up. I've no doubts it's fun (and useful), lots of good heads on the project. Best enjoy this time, I expect to be with you fairly soon, asking questions, making rude noises, scaring the women and horses. You know, the usual stuff?

Thanks again for the invite.

OF

 

[stickstones]

How in the hell did I finish the thread and not see one post by @Vape Dr.? This is right down his alley!

 

[Vape Dr.]

How in the hell did I finish the thread and not see one post by @Vape Dr.? This is right down his alley!

Hey Sticks! Hope you are well!

I didn't even know this thread existed!
Thank you for showing me my friend!
Very cool thread and it is right up my alley!

I have a feeling I will be here very often!

Got some catching up to do!

 

[Pipes]

@Pipes : wow that's not even a hot spot anymore, it's a black hole bowl!

Yep, very pleased. Purposely, over defined the area slightly...lol. But believe it or not it tasted that bad and did not combust even though it looks like it.
I'm not the guy to ask about taste, but I swear it tastes sweeter now too. Good enough that from here on out it's going to be the standard for my Projects.
Here's a couple pics of the technique I'm now using.

 

[Slow Draw McGraw]

Lots of badass people here!!!!
Welcome all!!!


I'm still running 3.01 TCR 130 and using a short solo stem with a screen making the bowl smaller. I used it yesterday and got the whole bowl brown with no charring or combustion with out stirring. I can't get it as dark as Pipes finished product. But im happy so far running as is.
I'm not good at coil design of building, but I imagine it's better. May have to step the game up!

 

[nondarb]

I have plenty of other ideas but honestly, I'm so impressed with what such a tiny coil can already achieve in the Project... is it worth it? I mean, once the hotspot issue will be solved, I'm unsure I would need anything more. This thing just rocks and is so fast! I can really get big rips with it already. I'll bring it to a music festival this evening, gotta dissipate that linseed smell!

After experimenting with several RTA's and lots of different coils and sizes I've arrived to the same conclusion. Its a great compromise of speed and efficiency. I'll eventually start tinkering at it again and make a few decks of my own.

Glad to see new faces on board, this is getting exciting!

 

[Quetzalcoatl]

One hit. I'll be trying out the new coil setup later on.

 

[Pipes]

Just an update for those on my waiting cache.
Unfortunately, the new thinner diameter, thicker walled tubing has not worked out. Too many alterations needed for it to work. Also, decided it would cause compatibility confusion down the road. I have now got two orders in for the original 14mm piping. The first of which could arrive any time but hard to say.
Hang in there. With the new coil design, you guys may be the luckier ones.

 

[Renthispace]

Thanks for keeping up the hard work pipes! Too bad about that metal tubing not working, worth a shot!

Regarding the new coil design...I was looking at it and it seems like there may be another hot spot with the coil being outside weighted towards the top. Obviously the only way to know is to test, and your test pictures from above do not seem to display the hot spot I am speaking of. Either way, I doodled another potential design. It's a small change over your new design to try and even out the inner vs outer coil while keeping the coil mass evenly distributed. I believe it shouldn't be too hard to bend and test.


Looking forward to The Project!

 

[Pipes]

I think that coil will definitely have a hot center. But never know for sure until it's been tried.

I'm quite satisfied with the result of the V coil. The heat pattern is like a horse shoe. If you look closely at the first picture I posted above you can see it. Here is a picture with less heat. Might move one more coil loop for the upper outside. This adjustment can be done afterwards which is kind of cool. And adjusting the V angle can also be done at any time after mounted.



Showing off coil design porn is good practice. We all can get ideas from them.
And since we're on the topic.

Check out the "Atomic Coil":



Never tested. The toothpicks are intended to burn off while getting the coil gets red hot for the first burn. The reason would be for shape locking only, heating up this hot would be for the initial heat up only.
Made by wrapping around a popsickle stick with one end of wire running back down the center. Pull out the stick and gently twist the coil making it go into different shapes.

 

[Dan Morrison]

@Pipes , Very neat!

 

[WakeAndVape]

@Pipes will the new coils be compatible with the current setup? Ifso...I would be interested!

 

[Pipes]

Absolutely. That's the core intention of this endeavor. Making a decently working device which is wide open for different coil designs and keeping it as easy and cheap as possible to make changes or updates. Keeping all the ideas and changes open source with no hidden secrets or tricks. A "peoples" vape so to speak. A $10 buck spool of element can bring much fun and self satisfaction. Along with some frustration of course, as you screw up a few coils, is just part of the game. And we are here to advise and help out if one has a hard time with the DIY part. I really want to encourage the owners to get into the coil making themselves as much as possible but OTOH, will not abandon if comes to that point.

 

[WakeAndVape]

Absolutely. That's the core intention of this endeavor. Making a decently working device which is wide open for different coil designs and keeping it as easy and cheap as possible to make changes or updates. Keeping all the ideas and changes open source with no hidden secrets or tricks. A "peoples" vape so to speak. A $10 buck spool of element can bring much fun and self satisfaction. Along with some frustration of course, as you screw up a few coils, is just part of the game. And we are here to advise and help out if one has a hard time with the DIY part. I really want to encourage the owners to get into the coil making themselves as much as possible but OTOH, will not abandon if comes to that point.

I want to make better/more coils as well...it just isn't my strong suit.

Maybe I just need to do it more and build the confidence...

 

[E0x]

was a bit hard the new coil but i think i get it right with a 0.55ohms reading , here is album with my second try , i will testing it today a little bit but the hard testing will done the weekend

http://imgur.com/a/nWMEM