Ok, I just did another test video. What I was testing was how many drops I could get in an empty Brass 'Rose' screen mod and an FRF PTB mod. In an earlier test I found out that I was able to top off a Brass Rose with 15 drops so I also wanted to include in this test how many drops it would take to top off an FRF PTB mod.
I am able to get 20 drops into an empty 510 round tip cart. That said what I found was I could get 19 drops in a new FRF PTB and a new Brass Rose mode. I also found that I was able to top off an FRF PTB mod with 15 drops. So, just speaking of capacity, the FRF PTB and the Brass Rose are the same. Again, this is just from one experiment. There are other factors such as type of juice and droppers, I guess, but I tried to make those as consistent (as I was willing to)
All this being said, I would not necessarily put that many drops in a cart especially when topping off. When Im topping off I am usually not in a position to blow out my atty. I really dont even care how many drops Im topping off with. I am usually leaving the house or leaving the office for an hour or so and dont what to take everything but I dont want to run out of juice. So I would grab a battery out of the PCC and top off by touching the dropper head on the edge of whatever material is in the cart that day and squeeze until I see it pooling, then use the bottle to suck some juice back out.
The times I would use that much juice in a cart is if I have a minute to blow out the atty. That way I know that the atty gets some juice and I dont flood it or get some juice in my mouth.
YouTube - 510 Cart Capacity Compare Brass and PTB
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