? How to keep the cotton from caving into a vertical coil build

[Gahh]

I love the hobby part of vaping so I'm always up to the task of re-building the stock coils.
The problem I cant seem to master is:
How to keep the cotton from closing in on the coil and shutting down the air flow.
I tried numerous methods but I can't figure out how the Chinese get the vertical coils to hold their round shape.
I like a good easy air flow. I'll build the coil on a 4mm rod keeping the spacing even and close. Build the coils using the coil/wire build chart so as to get the .5 ohm coil I prefer.
Most of the time the coil will work beautiful , but after a while the air flow becomes restricted. When looking into it....I find the cotton has collapsed into the coil.
I've tried using a 3/8 piece of cigarette paper as the first wrap around the coil. This interferes with the flavor, and the coil still gets closed up.
I've watched hundreds of builds on YouTube but very little is said about this issue..
Anybody have ideas about this?

 

[Izan]

Hi Gahh,
What atty are you building?
What kind of wire and what awg?
What kind of cotton are you using?
How long does it last before the collapse?

Cheers
I

 

[Gahh]

Hi Izan,
The problem I have with cotton collapsing in on the coil happens on 50% of my builds.
Can't tell what was the difference from the good half.
At this moment.......
Re-building a Melo 2 stock coil..,,
22ga. Nichrome..,,{on a 4.80mm rod}
Japanese Organic Cotton..,, (60mm * 50mm sheets)
(( When I get this problem it usually happens after 50-100 hits ))

 

[Gahh]

Hi Gahh,
What atty are you building?
What kind of wire and what awg?
What kind of cotton are you using?
How long does it last before the collapse?

Cheers
I

Hi Izan,
The problem I have with cotton collapsing in on the coil happens on 50% of my builds.
Can't tell what was the difference from the good half.
At this moment.......
Re-building a Melo 2 stock coil..,,
22ga. Nichrome..,,{on a 4.80mm rod}
Japanese Organic Cotton..,, (60mm * 50mm sheets)
(( When I get this problem it usually happens after 50-100 hits ))

 

[Izan]

It's a head scratcher for sure...
I've had decent luck using the top/bottom "layer" from KGD or similar as the first wrap or two around the coil. I tend to use rayon for the balance of any wick needed.
Do you find that the loosely packed/wicked coils last longer? I'm thinking your cotton might be expanding a bit more than anticipated.

HTH
I

 

[mcclintock]

The (older) ones I've taken apart use NR (non-resistance) welded wire assemblies, the top and bottom wraps of the coil don't actually heat they just support the wick which can then stop right at the end of the coil.

 

[sorrynomore]

When this happens to my rebuilt Joyetech Ego CL coils I take off the drip tip and open it up a bit with a wood toothpick.