Do those re-fillable carts not have a hole at the top?( Where you would drag from) I've seen 2 videos already where they open the cart, take the poly out, put the spring in, and start to fill it. Unless its just that I haven't tried, and not noticed that the juice wont drip out of the small hole. Thanks in advanced. By the way, I originally started out with those pre-filled carts (pack of 5) but the first 3 seemed to do jack! I just started dripping yesterday(after completing my first juice) and love it, but now I want to get prepared for the road where dripping will be a bit harder. Thanks in advanced for all the help.