That is where the problem I described, is focused...
"Stopping undesired fluid from dropping"...
That is because the bottles you use, have large holes, and the only thing holding fluid in the bottle is the lack of air. (Sink a cup in water, hold it upside down under the water, now pull it up without the lip of the glass getting exposed to the air. The water will stay inside the cup with that large orifice.)
When you use a small enough orifice to stop free-flow of dripping liquid, you now require pressure to expel liquid.
In essence, if you shook the bottle you have, or touch a paper-towel (wick) to the tip of the bottle, all the contents will pour out without any pressure applied. This happens because the turgor-pressure and liquid skin will pull to the wick, allowing air to pass by the mouth of the bottle, and into the bottle. (The same way our carts work now. This would just make this a complex cartridge, with a button that helps it drain faster.)
If this were a hookah-style pipe, this idea would be perfect. The bottle could sit up above the coil, without touching the actual coil, suspended in a glass neck. You would be able to see the hot-coil, and be able to drip another drop, and see the drop, and the vapor production. The bottle would be safely away from the hot coil, and the fluid would stay suspended without the need for a mini-orifice for dripping.
You also need to remember, every formula does not have the same viscosity. VG and PG and water and flavor all have separate viscosity. (Fluid thickness.)
While one fluid is easy to push through a dropper, another one may be too difficult, or too easy.
A mini-bulb pump may solve that problem, but it brings other problems to the table. (Rubber decays and has many toxins, not suitable for inhaling when heated or decaying from oil/chemical contact.)
Soft plastic bulbs help, but they still require a rubber valve-stopper.
The only other alternative would be a normal liquid pump, such as in a spray bottle, which uses a spring and ball-bearing as the valve. Or to have a micro-precision piston style pump, which does not require much pressure to operate or complicated valves. It works similar to 2-cycle engine, using a slip-ring.
(But now we are getting back to more complicated and expensive alternatives.)
None of that will stop the coil from burning up. That happens in a second, and can't be judged by the level of vapor you "Think" is coming out. By the time you realize there is no more vapor, it is too late, and the coil has fried. (Thus is the problem now, since these things don't detect when they are dry, and stop feeding power to the coil. EG, the high failure rate when the flow stops or the cartridge filling is not adequately touching the coil.)
It only takes one hair touching the opening to pull the liquid out of the dropper. (One with a porous residue build-up on the surface.)
Also, if condensation builds-up on the nozzle, that can cause it to drain as the bottle surface begins to get that same residue build-up, that becomes a porous wick surface.
I still think that idea would rock in a mini-hookah.
"Stopping undesired fluid from dropping"...
That is because the bottles you use, have large holes, and the only thing holding fluid in the bottle is the lack of air. (Sink a cup in water, hold it upside down under the water, now pull it up without the lip of the glass getting exposed to the air. The water will stay inside the cup with that large orifice.)
When you use a small enough orifice to stop free-flow of dripping liquid, you now require pressure to expel liquid.
In essence, if you shook the bottle you have, or touch a paper-towel (wick) to the tip of the bottle, all the contents will pour out without any pressure applied. This happens because the turgor-pressure and liquid skin will pull to the wick, allowing air to pass by the mouth of the bottle, and into the bottle. (The same way our carts work now. This would just make this a complex cartridge, with a button that helps it drain faster.)
If this were a hookah-style pipe, this idea would be perfect. The bottle could sit up above the coil, without touching the actual coil, suspended in a glass neck. You would be able to see the hot-coil, and be able to drip another drop, and see the drop, and the vapor production. The bottle would be safely away from the hot coil, and the fluid would stay suspended without the need for a mini-orifice for dripping.
You also need to remember, every formula does not have the same viscosity. VG and PG and water and flavor all have separate viscosity. (Fluid thickness.)
While one fluid is easy to push through a dropper, another one may be too difficult, or too easy.
A mini-bulb pump may solve that problem, but it brings other problems to the table. (Rubber decays and has many toxins, not suitable for inhaling when heated or decaying from oil/chemical contact.)
Soft plastic bulbs help, but they still require a rubber valve-stopper.
The only other alternative would be a normal liquid pump, such as in a spray bottle, which uses a spring and ball-bearing as the valve. Or to have a micro-precision piston style pump, which does not require much pressure to operate or complicated valves. It works similar to 2-cycle engine, using a slip-ring.
(But now we are getting back to more complicated and expensive alternatives.)
None of that will stop the coil from burning up. That happens in a second, and can't be judged by the level of vapor you "Think" is coming out. By the time you realize there is no more vapor, it is too late, and the coil has fried. (Thus is the problem now, since these things don't detect when they are dry, and stop feeding power to the coil. EG, the high failure rate when the flow stops or the cartridge filling is not adequately touching the coil.)
It only takes one hair touching the opening to pull the liquid out of the dropper. (One with a porous residue build-up on the surface.)
Also, if condensation builds-up on the nozzle, that can cause it to drain as the bottle surface begins to get that same residue build-up, that becomes a porous wick surface.
I still think that idea would rock in a mini-hookah.
