Temp rises very fast after dry burning SS316L coil

[Milkbread]

I have built my usual 2x26awg twisted, 3mm ID, 7 wraps spaced, SS316L coil yesterday, and it came out to about 0.34 ohms. The coil was only gently heated (no glow) to check for evenness. I then locked in the resistance @ 0.34 ohms to ensure stability. (I hate the very slight fluctuations of refinement)

My set up is DJaquith's SS316L profile, 40W, no preheat, temp set at 200 degC.

I was happily vaping it with the Engine Nano. So after 6 tanks or so, this afternoon I felt that the cotton wasn't wicking very well anymore. I took it apart, removed the cotton and dry burned it. I used power mode 10W and let it glow, followed by a quick rinse in tap water. I also brushed it with a pipe cleaner to remove all the gunk. Final rinse was done and the coil was dry burned at 10W again till glowing and dry.

The coil settled at a dark grayish colour after cooling down. After rewicking etc, I took a vape and I noticed that it hit my temp setting of 200 degC way faster than this morning.

Do any of you TC SS coil users experience this as well? Is there a better way of completely cleaning the coil?

Before cleaning the coil
 
After cleaning the coil

[dwcraig1]

If it were mine I'd be looking at the wick, too loose inside the coil perhaps. Just a thought.
The coil looks "electrically' the same to me.

[Milkbread]

dwcraig1 said:

If it were mine I'd be looking at the wick, too loose inside the coil perhaps. Just a thought.
The coil looks "electrically' the same to me.

Actually I've gone through more than 10 different type of coils with this issue while trying to find the perfect one for the engine nano over the last 3 weeks. I would say that my wicking is safe as I use Muji organic cotton, each piece of cotton cut into 4 strips and the top and bottom layers removed. The wick thickness should be quite consistent. Length has always been cut so the ends are barely reaching the deck base, fully fluffed. I have to do this if not the deck will flood when refilling. I suspect that the properties of this SS wire is changing after it turns dark gray based on my observations. On the first new coiling, if I don't glow it, the temp won't rise so fast. But if I glow it completely, it will. I suppose it has to do with the wire I get from my local supplier. Will have to find an alternate source and verify. In the mean time, all I can do is try not to glow the coil, although it's hard to get it really clean if I don't. I wonder if anyone else is experiencing this phenomenon

[dwcraig1]

I use pretty much only Unkamen's 430, but when I have had that happen to me it was wick too loose in the coil.
Your cold ohms/live ohm's is consistent in both examples

[Milkbread]

I tried what you mentioned, giving it a tight pull of cotton across the coils. Wicks well with the ends thinned out.
However, the extremely fast rise in temp detected is still the same. I have to run my setup at 220 degC instead of 200 now in order to get a decent vape. 

I did note that when the temp hits, the wattage running is higher than before. I attribute that to the better wicking keeping the cotton wet and it's a great tip from you. 
I am rather concerned of choking the cotton in the coils. When I ran kanthal claptons previously, I had to make the cotton looser in order to reduce spitting.

At least it's still working, although I'm still trying to get to the bottom of this and I feel that it's still the wire/coil. I'll try my best to get some other wire, especially SS430 try out.

[dwcraig1]

316/317 is a challenge of sorts, 430 is just well normal. 

[Asmodeus]

Milkbread said:

I suspect that the properties of this SS wire is changing after it turns dark gray based on my observations. On the first new coiling, if I don't glow it, the temp won't rise so fast. But if I glow it completely, it will.

It may.  I dry burn a coil every two days at about 50-70W.  Full screaming red hot - then quench it under water and scrub with dawn and a tooth brush.  I usually get about a month out of them or so.  They are big clunkers, fused clapton between twisted, or clapton and fused clapton.  .06-.09ohm.  3.5-4mm ID.  I burn them when I form them.  So... maybe I just never notice.  I think the gray is the crud you aren't getting off... because when I scrub them for the first week or two they come out shiny still.  

Is there an issue with bumping the temp 20-30*?  Why don't you just burn them in the beginning when you make them, that way once it's set - it's set even if you burn them to clean them?  The DNA will hold your desired temp like a boss.  So isn't faster better anyway?