When fillling a brand new, dry, fresh carto, how many drops ... and how long should it sit (upright?) in the carto before he attempts to vape?
I find each carto has its own personality, but in general 20 to 30 drops. My personal method when drip filling is to tilt 45-ish degrees, drip in about ten drops at a time as I rotate the cartomizer so it soaks in all around, then look at the top of the fill material. If it's soaked in already, repeat right away; if not, wait until it does soak in the top and repeat. I do this until I hit 20-25 drops, and if a quick blow through doesn't make a mess I'll go for five more drops. I've had some standard sized cartomizers take 35 drops this way.
Another way to fill is with a little device I like to call the Cartomizerfillinator, but that's better suited to mass filling or those who might have difficulty filling with the drip method (bad eyesight, motor control issues, etc.). You can look up the thread if you want but it doesn't sound like you need it.
I got the pre-filled menthol carto into a better mood (blew it out, ran the handy-dandy paperclip through the air hole, to make sure it was totally clear...
Be careful with running anything all the way through the cartomizer from top to bottom - that can be a great way to kill it!
Depending on how it's made, the cartomizer will have its heating coil(s) either running vertically up that tube in the center, or running horizontally across the tube. If your paper clip hits a coil just the wrong way it could possibly either break the connection "open" so that it just doesn't fire up, or (worst case) break the connection "shorted" so that when the battery is activated it's basically being shorted out, which could kill the battery, make it heat up or even vent its innards at you.
It's fine to use a tool to make sure the center tube is relatively clear, but if it hits or bottoms out on anything, don't keep pushing.
This is kinda fun!
That's why it becomes a hobby for so many of us!
I told him to take a light draw, not to really suck on it. That's solid advice, right?
As solid as any. Different cartomizers have different draws and everybody draws differently. The main thing is knowing that drawing on an e-cig is going to be different from the real thing, then finding whatever method works best for you.
Sounds like you're doing fine. If it worked perfectly for you guys right off the bat, most of us would be jealous.