bubbles.......

[mediocre toker]

I see a lot of people using tanks but not understanding the science behind their use.
This comment is aimed at the new vaper that has just bought an rta atomiser that is bottom coil.
Essentially what I want to stress is the need for the tank to be filled from the bottom.
Why?
If you fill from the top what you are doing is creating an air bubble in the top of the tank. That air bubble has an amount of pressure inside it. As you use the juice inside you tank the air bubble gets bigger and therefore so does the air pressure. Eventually the pressure gets so great that the air bubble just pushes your juice out of your tank causing flooding.
The correct way is to fill from the bottom.
When you fill from the bottom you are still creating an air bubble but as soon as you put your screw back in and start using the tank something entirely different happens.
The air bubble rises to the top therefore trapping it inside your tank with an amount of air pressure inside it. This pressure again pushes down on your juice but because the airbubble started at the bottom and because it is lighter than the juice that it's suspended in it tries to escape through the top of your tank. But it cannot go anywhere. Also as the bubble gets bigger when you use your juice up the air pressure inside the bubble remains the same even though the bubble is bigger.
This alone can cure your flooding problems ( we'll get to wicking later).
I recommend a 10% air bubble to juice ratio. So on a tank that takes 3 mils fill the tank with 2.7 mils maximum
Hope this can help you new tankers out there

 

[roxynoodle]

Some tanks can only be top filled though. I probably top fill half my tanks without issue. There is a method to insure no flooding. Close off the air. Fill. Invert during the last half turn of the top cap. Open air while inverted.

The Kayfun 4 and Epoch D1 have a method for closing juice to the chamber while top filling. And other attys can have the juice control closed for filling.

 

[93gc40]

All you have to do is invert the tank top filled tank, to establish the vaccum.

 

[twgbonehead]

If you fill from the top what you are doing is creating an air bubble in the top of the tank. That air bubble has an amount of pressure inside it. As you use the juice inside you tank the air bubble gets bigger and therefore so does the air pressure. Eventually the pressure gets so great that the air bubble just pushes your juice out of your tank causing flooding.

Sorry, but the above statement makes no sense to me. If the bubble gets larger, without more air being added, the pressure will decrease as the bubble gets larger.
If more air can get in, then the bubble is at atmospheric pressure (which is relatively constant).

 

[kkiet]

Sorry, but the above statement makes no sense to me. If the bubble gets larger, without more air being added, the pressure will decrease as the bubble gets larger.
If more air can get in, then the bubble is at atmospheric pressure (which is relatively constant).

Totally agree with this.

 

[mediocre toker]

When you fill from the top the bubble that is formd has the force of gravity acting on it so that as the juice is used the gravitational force inside gets bigger until the juice gets low enough inside the tank and then you can get leakage. Whereas filling from the bottom the gravitational force is negated by the bubble wanting to fight its way to the top. The air pressure in the bubble when filling from the bottom gradually decreases in line with the fall of juice thus creating an equilibrium inside the tank

 

[tedigram]

Haha what. I feel like there's some real fundamental misunderstanding of air pressure and gravity going on here. For one, gravitational force is not changing. Ever. Even if it did have anything to do with the air bubble in a tank, which it doesn't really. I think you need to check your science.

 

[mediocre toker]

Maybe you're right. I've been thinking too long about this subject and have obviously come to the wrong conclusions about what is going on inside my tank. So what is actually going on in there? Tanks that I have used do leak when filled from the top, but in my experience filling from the bottom counteracts this. I came to the conclusion through experimentation with different tanks both filling from top and bottom and assumed that the air bubble pressure created in the bottom filling method was in some way pushing past the juice to get to the top of the tank causing some displacement within the tank. Whereas from the top filling was only getting leaks after the juice had reached a certain point. Explain please. This is doing my nut in...

 

[Elizabeth Baldwin]

Maybe you're right. I've been thinking too long about this subject and have obviously come to the wrong conclusions about what is going on inside my tank. So what is actually going on in there? Tanks that I have used do leak when filled from the top, but in my experience filling from the bottom counteracts this. I came to the conclusion through experimentation with different tanks both filling from top and bottom and assumed that the air bubble pressure created in the bottom filling method was in some way pushing past the juice to get to the top of the tank causing some displacement within the tank. Whereas from the top filling was only getting leaks after the juice had reached a certain point. Explain please. This is doing my nut in...

You are almost correct. Some tanks are designed to be filled from the bottom because any trapped air will cause leakage. When you fill from the bottom, no air gets in. It's in a vacuum. When you fill from the top you let a small amount of air in which will cause some leaking depending on how much air was trapped.

 

[DaveP]

What actually happens with a tank that has no bubble is called hydrostatic lock.

If you completely fill a tank and don't leave room for the air bubble, you can't draw from it. Why? In order to vape the juice has to leave the tank when you pull a vacuum on the drip tip. The small air bubble expands when you draw and allows juice to leave and feed the coil.

If there's no bubble, the juice is hydrostatically locked into the tank because there's nothing to expand. Liquids don't expand (enough) to allow juice feed. Air does. You must have a little air in the tank that can expand to allow juice to feed when you draw.

As you continue to vape, air is drawn into the tank a little at a time and the bubble increases in size. The bubble grows because vaping creates a vacuum. After you vape, air is drawn in through the air hole, passes around the wick into the chimney, and out into the tank to equalize the pressure in the tank to equal the atmospheric pressure outside the tank. Depending on the condition of the o-ring seals, you may experience more leakage as the juice gets lower and the air bubble in the tank grows larger.

It's all like a hamster water bottle. When you invert it and hang it on the cage, no water escapes. When the hamster takes a drink water exits the bottle and air enters the spout to equalize the pressure.

 

[TheotherSteveS]

Maybe you're right. I've been thinking too long about this subject and have obviously come to the wrong conclusions about what is going on inside my tank. So what is actually going on in there? Tanks that I have used do leak when filled from the top, but in my experience filling from the bottom counteracts this. I came to the conclusion through experimentation with different tanks both filling from top and bottom and assumed that the air bubble pressure created in the bottom filling method was in some way pushing past the juice to get to the top of the tank causing some displacement within the tank. Whereas from the top filling was only getting leaks after the juice had reached a certain point. Explain please. This is doing my nut in...

I dont quite understand why you started this thread with a lesson, and have now become the pupil?!?!

 

[zoiDman]

Never Really have given Hydroscopic Pressure or the Ideal Gas Law much thought when it comes to RTA's.

I just Squish e-Liquid in with a Luer Loc Bottle and the Mash the Power Button down to make Vapor.

Seems to keep me from Smoking. So I must be doing Something Right.

 

[r77r7r]

Uh Oh, I have a side-fill carto-tank. Trap half the bubble then?

 

[zoiDman]

I want to know what to do if I have to Fill my RTA while on the Space Station?

 

[hypocritelecteur]

This is awesome.

Can someone tell me how to fill my tank? I'm at the bottom of the marianas trench. Wifi's not great here hurry

 

[r77r7r]

Or, or, my home-made hyperbaric chamber.

 

[zoiDman]

I wonder what the Effect of Going Down in a High Speed Elevator has on Filling a RTA?

 

[TheotherSteveS]

I wonder what the Effect of Going Down in a High Speed Elevator has on Filling a RTA?

depends who you are going.....nah I'll get banned if I post that...

 

[DaveP]

I guess we need an RTA with a tiny pressurized air tank built in for those who like to fill their tank without an air bubble. Just take it up to the gas station when it runs out of pressurized air.