Stainless Steel mesh, Oxide discussion.

[Boden]

Hmmm, sure I guess, but let's just say a standard Bic with a 1" flame or a cheap clear acrylic boxy thing with a similar conservative flame setting. I'm guessing 700-900F seems reasonable as a jet lighter gets an advertised 1300F and a small butane torch gets an advertised 2000F.

Emphasis on advertised.

I would say if the mesh is glowing orange it is burning at ~1450F which is about as hot as a disposable lighter will get. A jet lighter will get to around 2300F. A chef's butane torch will hit ~2600F. It is dependent on how efficiently the design of the burner mixes oxygen and fuel. More fuel than oxygen = cooler temps. More oxygen than fuel = hotter. Just like in an engine, run the mix too lean and you burn up the heads, too rich and you get a sooty mess gumming up the plugs. The problem with the chefs torch is that it burns very hot with a lot of excess oxygen which is what oxidizes the metal excessively.

 

[Boden]

Me Too, I hope the word spreads as fast that SS wicks are fine as it did that they may not be.

I'm not saying they are fine. I'm also not saying they are dangerous. I'm still saying we don't know.

One data point does not mean anything conclusive.

There is a lot more to figure out. Messing with oxidizers is chemically very very complex.

I know y'all want to skip to the end. Doing something scientifically is long and boring with lots of dead ends. I would love for this to be simple, one test and done. Problem is... it's not.

 

[Boden]

I really like this method: The Petar K Method - YouTube

I would use PG to do the burn but other than that

 

[gdeal]

I really like this method: The Petar K Method - YouTube

I would use PG to do the burn but other than that

and by chance Petar K has a thread here on ECF too....http://www.e-cigarette-forum.com/fo...-unoxidized-hot-spot-free-cleanable-coil.html

 

[MikeE3]

I guess I just hedge my bets - I run oxidized SS, non-oxidized SS, DIY Fishsticks, FC-2000 commercial, cotton, and bamboo. The only one I avoid is hemp. Just can't get used to the earthy/ropey taste it adds to the juice flavor.

 

[Boden]

I was just asked a question about the Peter K method elsewhere. I thought this might help some here.
-------------------
"Is this because the stainless steel can cause a short when it comes in contact with the wire?"

Yes, if and unoxidized/semi-oxidized coil touches a grounded unoxidized SS wick it will short to the wick at the top where the positive leg touches the wick before the fist wrap (you can see that happen in the video). The top cap is connected to the ground (-), if the wick touches the sides of the wick hole the wick becomes grounded. If the wick touches the bottom of the tank, which is also attached to the ground (-), it becomes grounded. Basically you want the wick to float with only the oxidized coil barely touching it.

"So how could they use unoxodized mesh without shorting out?"

Because the non conductive coating that insulates the coil from the mesh is on the coil. Once the coil has enough of an oxide coating, which with Kanthal is mostly Aluminum Oxide which is electrically non conductive, the coil insulates itself. As long as the wick is floating and you don't wrap the coil tightly which pushes the coil and wick together causing shorts between the wraps, there is no need to oxidize the wick.

 

[thedesbois]

I don't know if I understand this well. But here's what I read:


Latest test results:

Negative across the board at a test limit of ~.38mg/Kg I.e. .36ppm.

Then in another post, Boden mentions:

"I will say that this stuff is so nasty the exposure limit in liquids is 0.02 parts per billion per liter."

PPM being PPM... What I read from the test is that it is accurate down to 0.36pmm and anything under that will not be measured by that test procedure. So there might be a 0.24 ppm of CR(VI) in the tested liquids and it will report that none is present.

If 0.02 ppm is dangerous... I read that this test is irrelevant as it is not precise enough.

I must be misunderstanding something here... Confused I am.

 

[thedesbois]

I was just asked a question about the Peter K method elsewhere. I thought this might help some here.
-------------------
"Is this because the stainless steel can cause a short when it comes in contact with the wire?"

Yes, if and unoxidized/semi-oxidized coil touches a grounded unoxidized SS wick it will short to the wick at the top where the positive leg touches the wick before the fist wrap (you can see that happen in the video). The top cap is connected to the ground (-), if the wick touches the sides of the wick hole the wick becomes grounded. If the wick touches the bottom of the tank, which is also attached to the ground (-), it becomes grounded. Basically you want the wick to float with only the oxidized coil barely touching it.

"So how could they use unoxodized mesh without shorting out?"

Because the non conductive coating that insulates the coil from the mesh is on the coil. Once the coil has enough of an oxide coating, which with Kanthal is mostly Aluminum Oxide which is electrically non conductive, the coil insulates itself. As long as the wick is floating and you don't wrap the coil tightly which pushes the coil and wick together causing shorts between the wraps, there is no need to oxidize the wick.

Sounds like I'll put the wick hole insulator back in my ZAU. Hopping it doesn't melt. Can it melt?

 

[DrMA]

For those confused by all these units:
1mg/kg = 1ppm = 1000ppb = 1000µg/kg

EPA method 7199 used for Boden's samples has a detection limit (DL) of 0.4µg/L (=0.4ppbv=0.0004ppmv=0.0004mg/L), more than adequate for enforcing drinking water standards. The current enforceable drinking water standard for total Cr (CrIII+CrVI) is 0.1ppm (mg/L) = 100ppb
Basic Information about Chromium in Drinking Water | Basic Information about Regulated Drinking Water Contaminants | US EPA

Also FYI, EPA 7199 is an old method. Newer methods are now recommended by EPA (Method 218.7) for quantification of CrVI in drinking water, with a DL of 0.005ppb.
EPA

 

[asdaq]

I would say if the mesh is glowing orange it is burning at ~1450F which is about as hot as a disposable lighter will get. A jet lighter will get to around 2300F. A chef's butane torch will hit ~2600F. It is dependent on how efficiently the design of the burner mixes oxygen and fuel. More fuel than oxygen = cooler temps. More oxygen than fuel = hotter. Just like in an engine, run the mix too lean and you burn up the heads, too rich and you get a sooty mess gumming up the plugs. The problem with the chefs torch is that it burns very hot with a lot of excess oxygen which is what oxidizes the metal excessively.

That sounds more like it, I got my C and F mixed up with the jet lighter. My HF butane torch lists 2000F however, which might be low or realistic, I dunno.

 

[Boden]

I don't know if I understand this well. But here's what I read:


Latest test results:


Then in another post, Boden mentions:

"I will say that this stuff is so nasty the exposure limit in liquids is 0.02 parts per billion per liter."

PPM being PPM... What I read from the test is that it is accurate down to 0.36pmm and anything under that will not be measured by that test procedure. So there might be a 0.24 ppm of CR(VI) in the tested liquids and it will report that none is present.

If 0.02 ppm is dangerous... I read that this test is irrelevant as it is not precise enough.

I must be misunderstanding something here... Confused I am.

Yoda is that you?

The test is not irrelevant but at the same time not conclusive. It was just a step.

You're not confused, I was and still am somewhat. I was reading the concentrations allowable in CA water supplies. After reading that I have read many other low limits which were all over the place The EPA has it's guidelines, Osha has guidelines (which differ depending on which department you are looking at???) The EU has guidelines. They differ by as much as 1000X from the lowest to the highest. Fact is nobody has tested this on people (would be completely unethical) so the regulation bodys just make the levels so low that they are irrelevant to somebody trying to do an analysis but safe for absolutely everyone. The most constant LOAEL is .002mg/m^3 for dissolved Cr (VI) aerosols (1*). The average lung capacity of a human is ~0.006 meters^3....

I'm going to stop before I get into a mathematical equation so complex that even I have trouble wrapping my head around it. I regularly do gravity/speed/time calculations without a problem so to say this is complex is somewhat of a understatement. (If you want to talk about Event Horizon effects I'm your man) Basically, the amount of CrVI you want to be exposed to continually is really(10^4) small. The chance that it exists on highly oxidized SS is very high. These two things put together = my concern.


1*source: Chromium (VI) (CASRN 18540-29-9) | IRIS | US EPA

 

[Boden]

Sounds like I'll put the wick hole insulator back in my ZAU. Hopping it doesn't melt. Can it melt?

If it is Silicone, no. If it is Delrin, maybe.

 

[junkman]

So, is this thread dead now? Has anything been resolved?

 

[thedesbois]

Yoda is that you?

Thanks for the explanation. Excellent it is.

Yeah, I tend to word stuff as Yoda would. Don't know why. French is my mother tongue. Could be that. Green I am not.

 

[junkman]

Bump for news?

 

[Boden]

Patience my good man

 

[Koman]

Patience, yeah, that's a good virtue

 

[Stoneface]

Holy crap - quite a read. I have my first RBA sitting here waiting for me to rig it up. I've read the entire thread, plus some of the other threads linked to within. It seems that the "safest" set up so far is the Petar K with cotton wrapped under the coils? I understand that 2 tests have been performed, but are more of them planned?
Kudos and thanks to all of you smart and knowledgeable people! Being late to this party, I am thankful for those who have undertaken all of this and educate the rest of us.

 

[Boden]

Holy crap - quite a read. I have my first RBA sitting here waiting for me to rig it up. I've read the entire thread, plus some of the other threads linked to within. It seems that the "safest" set up so far is the Petar K with cotton wrapped under the coils? I understand that 2 tests have been performed, but are more of them planned?
Kudos and thanks to all of you smart and knowledgeable people! Being late to this party, I am thankful for those who have undertaken all of this and educate the rest of us.

Stoneface,

As far as wrapping cotton on the coils I don't think it would work very well as the wire temps you need to get a genesis style atty to work right is a bit higher that what cotton likes. You could try it but I would think it's gonna taste burnt.

Right now, as I am the only person working on this, more tests will have to wait. I have other things to work on.


Everyone,

If you don't react badly to using torch oxidized SS mesh you'll probably be fine.

If you have any reaction, metallic taste in your mouth, light sensitivity, temperature sensitivity, rash, itching, etc. stop using it immediately. (This has to do with allergies and chemical sensitivities like eating peanuts or sensitivity to PG)

As they say "At your own risk"

 

[gomjabbar]

I did the cotton condom method that petar k shows and its seemed to work fine. I am now using the method he describes here:

http://www.e-cigarette-forum.com/forum/modding-forum/359593-how-make-unoxidized-hot-spot-free-cleanable-coil-10.html

This doesnt seem like it should work but it does.