Do you still have the metal bar that came with the Zephr? I use that for the coil - and install it. Then roll the inner on the bar (200sf), then roll the outer on top of that. I then transfer this onto a screw driver, which is 2.4mm I think, and roll it until it slides reasonably easily inside the coil. Then I do the burn and quench. Sometimes helps to cut the bottom of the mesh at a 45° angle...