High pitched ringing? Melting coils? heh...

[purelyscientific]

Hey peeps,

I bought the kayfun V5 mini, my first RDA. I decided to go with stainless steel for my coil building wire switching from kanthal - my preferred type of wire. Long story short, after building a clapton and slappin' it in my deck I gave it a few pulses.....1....2....3....glowing hot......MELTED....FALLS ON THE CARPET. OH S***!

Yep, it melted. Wth....stainless steel is hard stuff!? It eats up drill bits at work like they're nothing. How the frick did it melt!?

Sooo, back to the drawing board I went. Seems this vet vaper has some catching up to do when it comes to building coils. (At least I didn't try to dry fire it with cotton in it like I did my first time testing a clapton a couple years ago. Don't judge me I'm used to silica! Hahaha)

OK, second coil in....pulse...1...wait...pulse 2....wait...pulse 3...wait. No melting. Good to go. Wicked up, juiced up, tank built, tank filled. vaping good.

One thing I noticed which I thought was odd was the ring the coil(?) gives off when I pulse it. It's not really noticeable too much when vaping but is when my RTA is taken apart and I'm pulsing it.

Now I'm no rocket appliance, but I am on my way to becoming an electrical mechanic. That said I reckon' the clapton coil I built is getting some harmonics going due to some type of eddy currents forming created by the wrap rate of the center wire vs the outside wire.

PS I'm using 26g inner SS with 32g outer.

 

[Shawn Hoefer]

I hear it on most of my SS coils. I don't think it's electrical, but different rates of expansion/shrinking as it heats/cools. I wouldn't have called it ringing... creaking, instead.

Make sure you pulse at very low wattages... SS can be effectively pulsed around 20-25 watts.

Sent from my SAMSUNG-SM-N910A using Tapatalk

 

[purelyscientific]

Hmm maybe we're hearing different things? It sounds close to 7000-12000H.

Thanks for the tip on pulse wattages. I defiantly won't be pulsing until its glowing hot again. -_-

 

[purelyscientific]

I just realized that we're actually creating an inductor which creates a magnetic field, so it could actually be eddy currents/harmonics creating a high pitched ring.

Scratch that, I think its magnetostriction causing audible vibrations at the upper frequency limits of human hearing.

Check this out "we hear a high pitch sound coming -presumably- from the inductor when we turn the system on. It appears that the sound is more noticeable when the circuit is drawing very small amounts of current. As the current demand increases, the sound usually becomes unnoticeable, but not always."

What might be the cause of high pitch sound coming from a switching regulator circuit

I'm reasonably sure that the 32g winding is vibrating against the inner core wire due to the magnetic expansion differential - (created by the different wire sizes/rates of expansion/contraction) which is created by the magnetic field, which is in turn created by the inductor(coil).

I may not be right on the money with this hypothesis, but I think I'm on the right track. Any electrical engineers out there want to take a shot at cracking this mystery?

 

[Eskie]

I'm fortunate enough at my age to not hear annoying stuff like that anymore.

 

[DaveP]

The ringing in my ears prevents me from detecting the ringing in the coil ...

Just kidding.

My hearing is still in normal range. Maybe it's something to do with playing in bands for a lifetime! We've just started using high decibel protected in-ear monitors in the last few years. Too late!

 

[Opinionated]

I think I'd find that annoying.

 

[DaveP]

I bought the kayfun V5 mini, my first RDA. I decided to go with stainless steel for my coil building wire switching from kanthal - my preferred type of wire. Long story short, after building a clapton and slappin' it in my deck I gave it a few pulses.....1....2....3....glowing hot......MELTED....FALLS ON THE CARPET. OH S***!

Yep, it melted. Wth....stainless steel is hard stuff!? It eats up drill bits at work like they're nothing. How the frick did it melt!?

I looked up SS316 melting points and it's 2400F-2800F!