New Atomizer Prototype

[Scottes]

You can't just dip the nichrome wire into molten Pyrex - I would think you'd need some space for expansion when the wire heats up.


But.... Why are lightbulbs so big in relation to the filaments that are so small??? Even in a halogen for a mini-mag, the hollow space of the bulb is much larger that the filament. Could this just be a manufacturing limitation?

[Bubo]

:-) Obviously, it just spewed from my brain with no thought.. (I have a very poor censoring chip in my head!)

So there needs to be some wire expansion area... Hmmm... I may have access to a 1500 degree kiln - just have to go to the dollar store and get a Pyrex cup, that should be enough glass to last a while! And nicrome... Exploding glass - should be fun!

Okay, seriously though. Assuming that we can melt Pyrex, and dip a coil into it - can anyone think of something that we can "pre-dip" nichrome in that would create an expansion area? Say we pre-dip the nichrome in the magic stuff, let it cool/harden/solidify, then dip it in the molten glass covering everything except the leads. The heat of the glass burns off the magic stuff creating a bubble in the glass for the nichrome to expand in.... Make sense? Any ideas?

[Jason365]

Here is a link to quartz tube manufacturer. Thay claim they will build you anything you want. Dont know what its costs though But maybe they will make some samples so you dont have to order 1000 of them. It may be easier than melting pyrex and dipping a coil in to it.

quartz tubes, quartz wafer carriers, crystal growth quartzware, EPI quartzware, quartz plate, quartz window

[moktarino]

Hello, first post.

Anywho, I was thinking about this problem, and I was reminded of a time when I made temperature probes out of a thermistor on a wire and a glass pipette. I used a blowtorch to melt the tapered tip of the pipette shut and squashed it a bit onto the tip of the thermistor.

I have in mind an atomizer consisting of a thin-walled boron-glass (pyrex is a brand of boron glass) tubing, perhaps 2mm diameter, containing a coil of nichrome wrapped around a capillary tube with one lead going through the center of the smaller tube. One end of the tube being sealed, the other being sealed around the nichrome's leads that have been soldered on previously.

That would look somewhat like a lightbulb or radial capacitor. Alternately you could make it like the leads axial (coming from each side), depending upon the desired form factor.

I'm designing a DIY nicotine delivery device and am considering this method for the atomizer.

[Carlos49]

Originally Posted by Bubo

Wow - definitely 'outside of the box'!


Hey - wait a minute - what if we just dip the Nichrome coil in Pyrex glass?
That takes the air out of the picture, thermal transference is dropped, glass breakage is minimized, preheating is dropped, nickle foam around the heater is gone, bridge is gone, epoxy is gone... Electroplate the Nichrome leads with copper (in a thread somewhere) and the solder is gone too.

Make the glass/nichrome long enough to stick in the cartridge wadding and the only thing left is to figure out how to connect it to a battery.....

Okay... what am I missing - that's too simple....
(Oh yeah - how do you melt Pyrex....)

Sounds like a great Idea!!! Sometime the simple things are staring you right in the face.. I wish I had the equipment to try something like that.
Let me know how it goes !!!

[moktarino]

Keep in mind that borosilicate glass softens at 820C (around 1500F). That's softening, not melting. There are a few formulations that soften at lower temperatures (700C/1200F), however, but I don't think it will make that much difference. Anything organic would not be able to survive this, so that leaves out any form of epoxy.

The kind of heat required to melt borosilicate glass to the thinness required for "dipping" is pretty high. I'm not keenly aware of the viscosity/temperature gradients for glass, but if the softening temperature is 820C you could estimate that the "liquid-like" temperature is probably somewhere upwards of 1000C. The melting point for nichrome is 1400C, but you'd need to braze it onto the leads as any solder you might want to use would definitely melt below that temperature.

These temperatures make dipping out of reach for your home hobbyist (myself included). It might be possible to order a small run from a Chinese manufacturer of things like this, but your tooling costs are going to be a bit higher than any individual would want to pay.


You can certainly reach softening temperature with a standard propane torch, though, enough at least to squash the tube.

http ://cgi.ebay.com/350--KIMBLE-1/10-ml-Glass-Serological-Pipettes-Pipets_W0QQitemZ150378905407QQcmdZViewItem#ht_1234 wt_1150]350- KIMBLE 1/10 ml Glass Serological Pipettes Pipets - eBay (item 150378905407 end time Nov-07-09 09:54:59 PST)

More later.

[roadkilldeluxe]

Originally Posted by Vaporer

Pyrex glass will take fast temp changes and smaller wire is actually the opposite way to go. IMHO 36ga NiCr is around 20 ohms per foot. 40ga jumps to whoppin 70ohms per foot.

True, but it takes less amps to get it heated to a specific temperature. Unfortunately, I ordered 32,36,40ga and recieved 26,32,36 instead. So I guess I should just use 36ga to start with? What did you use for your coils?

Originally Posted by Jason365

Basically making it a cartomiser

I too, was thinking along those lines. My only worries were (1) having epoxy directly on the juice and (2) would the legs need to be insulated? I think this could lead to a very compact and clean system, though. I really like the design of the cartomizers.

Originally Posted by Bubo

Perhaps a drop of molten glass on the end to seal it instead? Thermal conductivity of air would take an extra second or two, I would think... but is it negligible? Smaller Christmas light.. Cut it closer to the top as time goes on and practice would make closer tolerances... Perhaps an On/Off switch to turn on a preheater?

I'd love to be able to seal it with glass. Just not sure how or if I have the tools. And the preheater is something I mentioned in an above reply. It might not be too bad... plus, if it's preheated it will result in almost instant vaporization when you hit the 2nd button since everything will be 95% ready.

As for your idea about encasing the coil in glass, i'd love to. In fact, I was looking up glassworking costs yesterday, but it takes about $1000 to get a decent start in glassworking/blowing. The easier way would be to get a tiny glass rod, stick the coil in there, and seal off both sides. Almost as good!

Originally Posted by Bubo

Assuming that we can melt Pyrex, and dip a coil into it - can anyone think of something that we can "pre-dip" nichrome in that would create an expansion area?

Maybe dip a really hot, thick Nichrome coil into glass, let it cool and shrink, hopefully small enough so that you can actually pull it out, and then "snake" a smaller Nichrome coil through. Seal the two holes. But I think this might be too much work.

Originally Posted by moktarino

Anywho, I was thinking about this problem, and I was reminded of a time when I made temperature probes out of a thermistor on a wire and a glass pipette. I used a blowtorch to melt the tapered tip of the pipette shut and squashed it a bit onto the tip of the thermistor.

Excellent, I wonder if I can seal off the glass bulb this way!

I have in mind an atomizer consisting of a thin-walled boron-glass (pyrex is a brand of boron glass) tubing, perhaps 2mm diameter, containing a coil of nichrome wrapped around a capillary tube with one lead going through the center of the smaller tube. One end of the tube being sealed, the other being sealed around the nichrome's leads that have been soldered on previously. [...] I'm designing a DIY nicotine delivery device and am considering this method for the atomizer.

Could you post any diagrams? (I love diagrams) Sounds great, though. How will you be sealing the tubes? I hope this idea (and hopefully some positive results) will help you out in your endeavors, and thanks for the input! Keep us updated with your projects!

[Scottbee]

I'll continue to follow this thread with great interest, but I've got to be honest with you.. I'm not personally sure I understand what you're trying to accomplish.

Let's say that you are ultimately successful with getting some nichrome put inside of a glass bulb or coating. And that you are able to figure out how to get the time constant down so that it heats up quickly enough. Then what?

You still need to devise a delivery mechanism for the e-liquid. And I can assure you that you're not going to just stick the bulb directly into the cart material. A quick test with a temperature controlled soldering iron will show you that it's a bit more complicated than that. You need a device that will feed liquid to the heated element in a controlled manner. In the case of the 510, that happens to be a wick that runs from the mesh at the top of the bridge to the nichrome coil. Those that think that the bridge itself or the mesh around it gets hot enough to vaporize the e-liquid are mistaken and don't really understand the complexities of an atomizer. The vaporization happens right at the coil, and no place else.

At best, your method only really helps to reduce the possibility of the nichrome coil getting oxidized.... It doesn't address the feeding of the e-liquid and it doesn't address the problem associated with the vaporization by-products being deposited on the heated surfaces.

I'm not trying to dampen the thinking process at all... just want to make sure that we understand what the end-game is!

[roadkilldeluxe]

Originally Posted by Scottbee

You still need to devise a delivery mechanism for the e-liquid. And I can assure you that you're not going to just stick the bulb directly into the cart material.

I'll admit I don't yet know how the delivery system will work, but isn't sticking the heating element into the filler exactly how cartomizers function?

[...] it doesn't address the problem associated with the vaporization by-products being deposited on the heated surfaces.

Hopefully this won't be too big of an issue, I think that the glass heating element will be much easier to clean than the traditional coil.

As for what I'm trying to accomplish overall... I guess to see if there's a better, more reliable atomizer (or fully reusable cartomizer?) that can be made. It seems like the high maintenance and somewhat low reliability of current ecigs turn people off of vaping. I'm hoping to get the ball rolling on a new design that will make ecigs a stronger competitor to analogs. Charging and refilling will always be an issue, but worrying about flooding/drying out/burning out/primer/buying replacements online/cleaning every night/etc doesn't have to be. (I hope )

I hope to one day not have to explain to everyone exactly how to use it, the "proper way" to inhale, etc. My friends are super interested in vaping but I can't imagine any of them making it past a few days once they realize how much harder it is than simply carrying a BIC and buying a pack at any gas station when you're out.

Keep the critiques and ideas coming! I'd rather figure stuff out and deal with obstacles sooner than later! Thanks everyone!

[Scottbee]

Originally Posted by roadkilldeluxe

I'll admit I don't yet know how the delivery system will work, but isn't sticking the heating element into the filler exactly how cartomizers function?

Not really. A KR808D-1 cartomizer certainly does have an exposed heating element, but it is wrapped in a layer of material that has a different wicking characteristic than the poly cart filler. That layer acts as a barrier between the poly filler and the coil... controlling the rate of liquid flow. And frankly, I don't think it works all that well.

I believe that the inside of a GreenCig cartomizer is more "traditional"... with a coil, a reservoir, and a wick that carries the liquid from the reservoir to the coil.

P.S. I'm right there with you on the need to simplify the use of PV's. I was hoping the cartomizer approach would get us there.. and maybe it's close. But I won't give up my 510 for a KR808D-1. The vapor production just isn't there. I'm hoping/thinking that we're just one or two generations away from something that we can readily recommend to the "unwashed".