Avoiding coil oxide layer vs. getting out hot spots

[Electro108]

so, I’ve read that avoiding pulsing and devopment of the rainbowy oxide layer is a good thing as it can introduce trace metals and whatnot into the vapor. This makes sense, however, I find it near impossible, even with spaced coils to get the hotspots out. I get much better performance and flavor from pulsing lightly and adjusting until the coil glows uniformly from the inside out. Does this correlate with anyone else’s experience? Using ni80 and SS, BTW

 

[sonicbomb]

Intriguing, there can be no hotspots with a properly spaced coil. Unless there were major irregularities in the composition of the wire itself, which is extremely unlikely.

Could you post some good quality pictures showing the issue?

 

[stols001]

I'm a bit confused as well. If you are gently pulsing at first, yes, I've seen coils turn rainbow colored, but if you heat them to an even burn, that coloring gets heated away. I was under the impression that doing that the first time actually starts the process of burning off any impurities in the metal, but I stand ready to be corrected. Also, you don't want to leave them in that state necessarily, you want to get everything fully annealed.

I have heard (depending on wire type) that overheating coils or dry burning them may produce some impurities, but more with titanium or nickel (which can melt, even). I think SS may produce some impurities if overheated, but the question is and remains, how much and is it harmful. I clean my SS wires mostly, and will gently pulse them but I don't heat them to red hot at all, and I'd hazard my "cleaning" method probably gets the wire as clean as (or cleaner even) than dry burning, but I'm merely erring on the side of caution, I'm not certain that anyone had completely determined how much impurities a SS wire will give off, and how harmful they are. And I do fully heat my coils the first time I'm using them. I have not noticed any ill effects from doing that, although I'm also not here to state they can't be present. I try to err on the side of caution usually-to a point. I also try to not overthink it either.

Best of luck, maybe someone can be of more definitive assistance, but that is pretty much what I've gotten out of the topic so far and etc.

Anna

 

[Myk]

I think you'll also find a lot of metal workers dispute the claims applied to all wire.
(All color on Ti is titanium oxide but as far as I know only the white gets air-born and is harmful. But you don't want to make Ti glow anyway or it catches fire, which is not as big of a deal as some make it out to be but your coil is popped after that. It doesn't burn well like magnesium does. It probably does release oxides into the air.)

 

[Electro108]

This is the coil. It is a ni80 fused Clapton. I tried using it fresh and still silver. While it worked, it worked a LOT better when I dewicked, cleaned, then started pulsing it in a dark room, and adjusting until all hot spots were gone and it uniformly heated from inside out. As you can see, it has developed colors that some deem bad due to oxide. I just can’t imagine not pulsing to get these hot spots out.

 

[MacTechVpr]

This is the coil. It is a ni80 fused Clapton. I tried using it fresh and still silver. While it worked, it worked a LOT better when I dewicked, cleaned, then started pulsing it in a dark room, and adjusting until all hot spots were gone and it uniformly heated from inside out. As you can see, it has developed colors that some deem bad due to oxide. I just can’t imagine not pulsing to get these hot spots out.

Hmmm, now that you put it that way, good question.

I'm still tryin' fig out what a properly spaced coil is.

Good luck all.

 

[Myk]

This is the coil. It is a ni80 fused Clapton. I tried using it fresh and still silver. While it worked, it worked a LOT better when I dewicked, cleaned, then started pulsing it in a dark room, and adjusting until all hot spots were gone and it uniformly heated from inside out. As you can see, it has developed colors that some deem bad due to oxide. I just can’t imagine not pulsing to get these hot spots out.

As far as I know claptons have to glow, especially touching claptons. All of mine have had a ton of random hot spots until glowed and poked. You could try heating liquid on it until it calms, but how are you going to know it's heating even without glowing it?

My original comment to the suggestion that making coils glow (those materials that can glow) was bad was that you can't work metal without making it glow. Cold work hardens it, glowing softens it. At some point when drawing it down the wire was annealed so it glowed (granted maybe annealed in an oxygen free environment, or the oxides were removed in the final finishing).
When doing touching coils, mesh wicked coils, wrapped coils, dual coils or anything else that isn't going to heat evenly you have to make them glow at least to check to see.

The suggestion to not make coils glow was not reasonable to the needs of most coil making. The suggestion that making them glow changes the molecular makeup doesn't seem possible. Even heating brass above the melting point of lead doesn't bring all the lead to the surface, only exposing new metal or melting does that.
Molecular structure yes, that is the purpose of annealing. But if it changed the makeup, metal wouldn't ever be what it was said to be. It would be something different depending on the atmospheric conditions on the day it was made. Foundries are not temperature controlled clean rooms.
Oxides formed on the outside of the metal yes. But as I pointed out above sometimes those oxides are needed to get even heating without hot spots which will overheat the liquids and create their own baddies if left alone.
You could probably glow in argon if you really didn't want the oxides but I'm not sure if that will cure hotspots with touching or wrapped coils, only good for annealing or checking duals. It's not really reasonable to use argon to make 10¢ coils.

It was admitted that like most every fear of vaping they were talking very minor risks.
If you want the safest vaping possible use SS single spaced coils without glowing in temperature control with as low of a temperature as you can stand below about 450°F, or 410°F if you use any VG. If any of these safety police rules make you think of going back to smoking, just vape.

Note I am an end product metal worker not a metallurgist. I could be wrong but I don't think I am (I can't be too far wrong or my stuff wouldn't work).

 

[sonicbomb]

From the picture it looks like a contact coil. Even if it is spaced, a clapton will always need pulsing to get the hotspots out as the contact between the core and the outer wire will not be perfectly even.

 

[MacTechVpr]

From the picture it looks like a contact coil. Even if it is spaced, a clapton will always need pulsing to get the hotspots out as the contact between the core and the outer wire will not be perfectly even.

Right on. And every one of those irregular separations a potential arc source whether clap's, twisted or other multi-wire variation. IMO what delivers us from evil so to speak is the fact that some level of pulsing is aiding in promoting an oxide layer to some extent.

These seemingly minute variations in the symmetry of the wind may seem inconsequential until you start to watch some of the videos of pulsed fresh winds to observe the arcing. Sometimes across the breath of the coil. Can it happen in operation? Sure. That's the downside.

Anywhere there's an inconsistent section of wick-to-wire contact which may allow rapid drying of the media. Then…your guess is as good as mine, as I don't see too many videos of our winds in operation. And none of this a problem for most of us but a challenge and mystery to every new rebuilding vaper.

I'm hoping things will slow down a bit here as @Myk's brought up some good stuff.

Good luck.

p.s. As to hot-spots with spaced, just about every other hand wind on Vivi Nova's when I started. And arcing! So bad it chewed wire down to the bone faster than a hot barbecue.

 

[Myk]

p.s. As to hot-spots with spaced, just about every other hand wind on Vivi Nova's when I started. And arcing! So bad it chewed wire down to the bone faster than a hot barbecue.

I'd have to look at how I was making coils then but I don't recall that with Vivi Nova. I was cramming a lot of wire into Pro Tanks with touching coils so they did need pulsed.
I also tried to make a TC Pro Tank that was a complete fail. I guess those press fit contacts weren't good enough to hold Ω for TC, at least when rebuilt.

Chewing wire down would have to be releasing metals into the vapor. I would have that with mesh wicked gennies. To my mind hot spots burning liquid and chewing wire down would have to be a lot worse than having the wire coated with oxides.

"We will repeat our honest opinion that dry-burning the coils will not make vaping similar or worse than smoking."
I heard Dr F about dry burning on Click Bank and the panic started was understandable the way he put it the first time. And I think when he came back to clarify it came out it was not a metallurgist that brought this up. I would yield to a metallurgist's greater knowledge. But someone with similar seat of the pants knowledge as me (including me) bringing stuff up is not the end of the conversation.

 

[MacTechVpr]

I'd have to look at how I was making coils then but I don't recall that with Vivi Nova. I was cramming a lot of wire into Pro Tanks with touching coils so they did need pulsed.
I also tried to make a TC Pro Tank that was a complete fail. I guess those press fit contacts weren't good enough to hold Ω for TC, at least when rebuilt.

Chewing wire down would have to be releasing metals into the vapor. I would have that with mesh wicked gennies. To my mind hot spots burning liquid and chewing wire down would have to be a lot worse than having the wire coated with oxides.

"We will repeat our honest opinion that dry-burning the coils will not make vaping similar or worse than smoking."
I heard Dr F about dry burning on Click Bank and the panic started was understandable the way he put it the first time. And I think when he came back to clarify it came out it was not a metallurgist that brought this up. I would yield to a metallurgist's greater knowledge. But someone with similar seat of the pants knowledge as me (including me) bringing stuff up is not the end of the conversation.

I hear ya. Concerned some inexperienced vapers trying to pick up rebuilding end up confused on the attributes of various wire metals. So for example a passivation layer on stainless is unavoidable and not necessarily harmful. Likewise with Kanthal, the alumina layer is intended by design, aids in preventing hotspots or shorting so beneficial. Understand what Farsalinos was striving at. But anything if pushed with too much power can have a downside. The matter is how and when; not, whether or not.

Yeah, the stuff with the early clearo's and high-res pushed with power could get real scary. And I saw plenty of legs chewed off and wondered the same thing (first month, I hadn't even joined ECF yet). Same thing with the early PT, Evod, etc. coil assemblies (sketchy insulator termination, extruding cut-off leads grazing the housing at the pin, too close to wall arcing, many). And one thing could overheat things to provoke another, etc. Then you're sitting there grommet burning, lead arcing and 3-turns burnin cotton with 3-not workin at all. It's throw the dang thing at the wall time. Looked just fine when I made it.

Is it possible to release some less than beneficial constituents? Well, yeah. But I'd rather understand why it might happen and not close any door to mitigating or eliminating the possibility. Why I dropped in on that thread along with many others. The title was deleterious and presumptive.

We've got a lot better hardware and a far, far better understanding of how and why things work today. Anyone quitting these days don't know what they're missing thankfully (mostly).

Good luck.

 

[Myk]

Understand what Farsalinos was striving at. But anything if pushed with too much power can have a downside. The matter is how and when; not, whether or not.

Hard to say in pictures/videos with white balance, but I've seen people going way above and beyond infatuated with the glow. There's usually no real need for that no matter what the goal is.

What is needed is for a metallurgist to step in to say what temperatures are bad for the different metals and then explain the color chart and what colors to stay below.
If it works to teach people like me to work with metal it would work to teach safer DIY coils without diminishing how the coils work. That would be much better than "don't do it".

 

[MacTechVpr]

Hard to say in pictures/videos with white balance, but I've seen people going way above and beyond infatuated with the glow. There's usually no real need for that no matter what the goal is.

What is needed is for a metallurgist to step in to say what temperatures are bad for the different metals and then explain the color chart and what colors to stay below.
If it works to teach people like me to work with metal it would work to teach safer DIY coils without diminishing how the coils work. That would be much better than "don't do it".

Agreed. Just wish more peeps were interested in the job. Would make for a more satisfied and engaged community.

Have a great weekend all and good luck.

 

[Chuck64]

LoL sorry, but some of us smoked 30 to 40 years putting god knows what into our bodies and there's worry over trace metals? I'm sure the poster means we'll but it made me chuckle a bit.

 

[MacTechVpr]

LoL sorry, but some of us smoked 30 to 40 years putting god knows what into our bodies and there's worry over trace metals? I'm sure the poster means we'll but it made me chuckle a bit.

Yeah right? And now they want to corral us down into these wee little cute podlets and put 'em all right back in there.

No, the concern over chem artifacts is valid (if not significant in actual measure). Knowledge is power, the ability to protect ourselves from our idiot detractors. But I sure do see where you're comin from and glad to be rid of that sh!!t.

Good luck.

 

[Chuck64]

Oh jeez don't get me started on those pods. And the price!

 

[Myk]

LoL sorry, but some of us smoked 30 to 40 years putting god knows what into our bodies and there's worry over trace metals? I'm sure the poster means we'll but it made me chuckle a bit.

I'm also a metal repair worker. I can try my best to get enviro kind acids and cadmium free solder but I have no idea what is in what I work on other than I can be sure I inhale my fair share of cadmium even trying to avoid adding to it.
Call me when you have something really scary.

 

[MacTechVpr]

As far as I know claptons have to glow, especially touching claptons. All of mine have had a ton of random hot spots until glowed and poked. You could try heating liquid on it until it calms, but how are you going to know it's heating even without glowing it?

My original comment to the suggestion that making coils glow (those materials that can glow) was bad was that you can't work metal without making it glow. Cold work hardens it, glowing softens it. At some point when drawing it down the wire was annealed so it glowed (granted maybe annealed in an oxygen free environment, or the oxides were removed in the final finishing).
When doing touching coils, mesh wicked coils, wrapped coils, dual coils or anything else that isn't going to heat evenly you have to make them glow at least to check to see.

The suggestion to not make coils glow was not reasonable to the needs of most coil making. The suggestion that making them glow changes the molecular makeup doesn't seem possible. Even heating brass above the melting point of lead doesn't bring all the lead to the surface, only exposing new metal or melting does that.
Molecular structure yes, that is the purpose of annealing. But if it changed the makeup, metal wouldn't ever be what it was said to be. It would be something different depending on the atmospheric conditions on the day it was made. Foundries are not temperature controlled clean rooms.
Oxides formed on the outside of the metal yes. But as I pointed out above sometimes those oxides are needed to get even heating without hot spots which will overheat the liquids and create their own baddies if left alone.
You could probably glow in argon if you really didn't want the oxides but I'm not sure if that will cure hotspots with touching or wrapped coils, only good for annealing or checking duals. It's not really reasonable to use argon to make 10¢ coils.

It was admitted that like most every fear of vaping they were talking very minor risks.
If you want the safest vaping possible use SS single spaced coils without glowing in temperature control with as low of a temperature as you can stand below about 450°F, or 410°F if you use any VG. If any of these safety police rules make you think of going back to smoking, just vape.

Note I am an end product metal worker not a metallurgist. I could be wrong but I don't think I am (I can't be too far wrong or my stuff wouldn't work).

Some great points to your post. I highlighted the fine points, particularly…cold work hardens it, glowing softens it. And to my understanding when you change the character of the metal, it's work attributes may as well. The reason is the crystalline matrix has changed. If in a good way, performance may improve.

That's been the gist of my encouraging knowledge on the use of strain and electrical pulsing (low-V) to promote alumina extrusion (insulation) and improve durability (rigidity). A wickedly simple approach that dispenses with the high-power pulsing or degradation of wire surface that can come from torching (the old way). Well, at least for Kanthal which imo is the easiest wire to work with for beginners.

I think the OP was just looking for a top-end temp limit for s.s., I think. Don't know really enough about all the grade variants to really say in practical terms (direct observation). Mebe someone already has. I've outlined my rec's for Kanthal in various posts elsewhere.

Good luck.

 

[Walee]

As mentioned above "hot spots" are simply shorts across wires. Heating or pulsing the wire so it will develop an insulation layer preventing the shorts. I have no idea what the health ramifications of this insulation layer are. I don't know it's molecular structure for every metal type. No idea where to "stack rank" that among the risk factors of life. I have to believe it is less risk that smoking, driving, or drinking tap water. Possibly equal to that of simply breathing depending on where you are breathing. Interesting muse however.

 

[Myk]

Some great points to your post. I highlighted the fine points, particularly…cold work hardens it, glowing softens it. And to my understanding when you change the character of the metal, it's work attributes may as well. The reason is the crystalline matrix has changed. If in a good way, performance may improve.

That's been the gist of my encouraging knowledge on the use of strain and electrical pulsing (low-V) to promote alumina extrusion (insulation) and improve durability (rigidity). A wickedly simple approach that dispenses with the high-power pulsing or degradation of wire surface that can come from torching (the old way). Well, at least for Kanthal which imo is the easiest wire to work with for beginners.

I think the OP was just looking for a top-end temp limit for s.s., I think. Don't know really enough about all the grade variants to really say in practical terms (direct observation). Mebe someone already has. I've outlined my rec's for Kanthal in various posts elsewhere.

Good luck.

I "torched" titanium to get some of the low end colors just to make it workable. Before I stopped using it I considered putting the whole roll in my kiln.

From what I know from knife making any temperature hot enough to vape with is annealing/tempering. That starts very low.
The temperatures Dr F threw out there were very basic and why I say we'd really need a metallurgist. Going by Dr F's temperatures yellow glow is the high number he gave, dull into cherry is OK, full cherry is getting far enough above his 700°C to avoid if it really is creating bad stuff. The colors are quite accurate, the problem is our perception of color is about as accurate as a computer screen.
I'm colorblind but I had schooling with someone who had seat of the pants experience standing over me.
These are the alloys of this ferrous metal (I'm non-ferrous but have some ferrous for tool making) and these alloys do this at this temperature and that is bad for the human body is beyond my pay grade.