Cotton flames!

[Treebeard]

I accidentally hit the fire button on my grand/RM2 with a dry cotton wick in it. Needless to say, it went up in smoke and flames....literally. I tweezered out the burnt cotton and then dry fired the ( Nichrome micro) coil to get any cotton fuzzies out of the coil but the coil curled up and melted three of the eight wraps together. Anyone ever see a coil curl up and melt? Can anyone explain this?

Battery never got hot and the spring didn't collapse. Only thing I can think of is that I didn't get all the cotton out of the inside of the coil and there was enough left over inside the micro coil to cause excessive heat.

P.S. In the interest of "science", I built another coil, threw it on the atty, wicked it, wet it, held my breath, closed my eyes, pressed the button.......... and it worked fine.

 

[Dturp]

I had one coil meltdown while dry burning never had any idea why? Maybe yours with the cotton leftovers is the answer?

 

[Rhapsodies Fire]

what kind of wire are you using??? Got pictures of the damaged coil?


No...I've not seen it, but that's not saying much.

I dry burn the hell out of my coils...and haven't had any melt.

 

[JC Okie]

That doesn't make any sense to me at all. I mean, I torch mine and dry burn them all the time....how could a coil melt? Amazing. And how could the cotton burning be hotter than a Bic lighter torching it if the cotton disintegrates when it's torched??!! The science on this one would be fascinating for sure.

 

[Dturp]

I don't know what his did but mine quite literally heated to orange then just sagged in the middle like a crumpled tin can. Only happened once never seen it since and i do dry burns every few days at most.

 

[Rhapsodies Fire]

maybe an inconsistency in the wire? I can't imagine how cotton would change the wire or the heat to the point that it would melt the wire.

 

[Mark8n]

He said it was nichrome, I'm sure that's the culprit

 

[pdib]

I've heard of something akin to this 3 times in the last two weeks. Always Nichrome. Maybe a quality thing? A poorly mixed batch? Didn't sift the metals before combining in a mixing bowl?

Anyway, I've heard of micros being referred to as a controlled short. I've meterred a couple right after dry firing, and they sometimes clock in at .1 or .2Ω lower in in resistance. (like a .5Ω coil meterring at .3Ω when it's still hot/warm). Not always, just sometimes. I wonder if these melting coils didn't just achieve a low enough resistance on dry burning to end up frying themselves. (Maybe in conjunction with a "poorly alloyed" ? batch of Nichrome)

Just a wild conjecture.

 

[Treebeard]

what kind of wire are you using??? Got pictures of the damaged coil?


No...I've not seen it, but that's not saying much.

I dry burn the hell out of my coils...and haven't had any melt.

It was Nichrome 28 ga. That wire below the coil is fused to the coil. The wraps on the far right were originally as tight as the rest of them. The way the coil moved was a weird sight to see as it was happening.

 

[pesky_human]

Yeah. Don't do that anymore.

 

[Treebeard]

I've heard of something akin to this 3 times in the last two weeks. Always Nichrome. Maybe a quality thing? A poorly mixed batch? Didn't sift the metals before combining in a mixing bowl?

Anyway, I've heard of micros being referred to as a controlled short. I've meterred a couple right after dry firing, and they sometimes clock in at .1 or .2Ω lower in in resistance. (like a .5Ω coil meterring at .3Ω when it's still hot/warm). Not always, just sometimes. I wonder if these melting coils didn't just achieve a low enough resistance on dry burning to end up frying themselves. (Maybe in conjunction with a "poorly alloyed" ? batch of Nichrome)

Just a wild conjecture.

May be a quality thing but I have some from this same roll on two other attys and have had no problem dry burning (yet). This is the first time I've tried Nichrome and I'm liking it better than Kanthal. Maybe it's coincidence that it happened immediately after the wick went up in flames.

 

[Treebeard]

That doesn't make any sense to me at all. I mean, I torch mine and dry burn them all the time....how could a coil melt? Amazing. And how could the cotton burning be hotter than a Bic lighter torching it if the cotton disintegrates when it's torched??!! The science on this one would be fascinating for sure.

That's exactly what I said to my son (except with a few expletives added in). I had burned the wire with a butane torch prior to mounting it and had it glowing. It doesn't make any sense to me either but it sure would be nice to know why if for no other reason than to avoid it happening again. I didn't know a battery could deliver enough current to melt wire.

 

[malkuth]

That might be good information to pass on to those that are doing the sub .5 ohm coils. If it can melt wire, what would it do to your face?

 

[Vapeaddikt]

It's gotta be a fault w/ the wire.

I've never had one do that.

 

[Raynman]

Hey don't worry I have this guy working on it.

 

[Treebeard]

Lol! Thanks, Raynman, I got a good chuckle out of that.

 

[Treebeard]

OMG! It happened again. This time on a different atty with wire off the same roll. I caught it before it was a complete melt down only melted on one end and separated from the post. It has to be a bad run of wire. I'm gonna trash this crap, pronto.

 

[mrwilliams2]

Did it happen on the same device? Of so, I would check that device very closely before using it again.

 

[Treebeard]

Did it happen on the same device? Of so, I would check that device very closely before using it again.

Same reo grand. I took it apart and can't see anything unusual. I've been using Kanthal and Rene 41 in it with no problems. I recoiled with Rene 41. So far so good.

 

[pdib]

I doubt that it would have to do with the device, or the 510. Any discrepancies there would result in less power getting to the coil, not more. (Total Speculation Here . . . .TSH)



. . . . . no, wait . . . "Total Speculation Here In This" . . .. .HAH!


. . . . . anyway: any kind of a short would mean, basically, no power getting to the coil (short in the device, not the coil). Other than that, dirty or poor contacts would also lead to less power, not more.


Upstart Battery? . . . surging and belching extra current to the coil? . . . . . .. Nawwwwww.