I don't have any good advice, only sympathy. I only have the black o-rings as well and my tank is really really really hard to get off. In fact I ended up breaking the last tank to get it off. Luckily I had lots of extra tube. But I had a hard time cutting this last piece. The tube cutter kept "walking" on me and instead of a cut I was getting a lovely spiral design up the tube. Wasted a good amount of tube on that round.
Just rebuilt it tonight and it's kicking hard!
As you can see I run a single wick. I bought a plain 510 connector from MadVapes and soldered a regular copper wire through the center.
Then I placed crimped a syringe needle tube onto the copper wire, use some tape to isolate the wire and tube and run it up through the top of the center tube.
Grabbed a 510 carto plug and trimmed it down so I could slide the syringe tube through it and squeezed that down into the center tube to seal it all up and keep out the juice.
Then I just take a long piece of wire (currently copper...yes yes I know it's bad) kink it a bit, and slide that into the center syringe tube.
What I really like about this setup is that it allows for total adjustment I can bend that wire to just the right spot and totally eliminate long leads coming off the coil!
Negative is a small screw with two nuts "threaded" down into a pin I jammed in the ground hole.
It works great. I rolled a new coil, oxidized the whole wick, used the cigarette paper method, wrapped my kanthal and boom!!! Awesome vapor!
This thing still rocks and I can't wait for the mini and the spartan hybrid!
Thanks Dan and Rusalka for the continued development of this awesome design!
I use a stainless steel hypodermic tube up the center. I crimp a piece of wire and place it in there