Just fixed one of these for a friend. He ordered it through SlowTech, as well as what they call a "Derringer V3" RDA.
I was going to convert the RDA to BF (FDV Pin) for him. Anyway, the bottle would not squonk at all .. time to mod!
The tubing was too big for the 510 pin (air leak #1), and the cap was allowing air through the threads (air leak #2).
I have some spare FDV squonk tubing from their Premium Squonk Kit which fit the 510 tightly, but didn't fit through
the cap. Used a dremel and an abrasive point to enlarge the hole in the cap. Tubing now fits tightly on 510 & cap.
For the cap I used a thick parts bin 510 o-ring on the threads. You can see the black line under the cap below.
Squonking like a champ now. Hope this helps anyone with the same issue.
Neat little mod. Wonder if the internals from an Artery Nugget would fit in here(?)
Cheers!