Ok..one more post and I am really done till Walmad delivers glass tubing. I have a bit of OCD with this concept and could not resist, so bear with me. (If I am beating a dead horse let me know and I will stop posting on the incremental stuff).
So, with my previous versions of ScubaQu, overall
vape was okay, not better than coil-on-wick. Without the top cap on the atty, in all the setups vapor production is great. However, when the atty was capped and I actually vaped, quality was just okay. Nothing to make me switch, even with ease of use factors. The issue IMHO is air-flow. Dan mentions this in his posts and made some suggestion on the angle of this airflow inlet. He mentioned offsetting the air hole to the wick. With the AGA set up I am using, I could not find a good angle other than directly on the wick. But even that did not get better than coil-on-wick vapor quality.
My objective was to get airflow above the tube opening. I was not ready to drill out my AGA, so I measured exactly where the air inlet was compared to the top of the glass tube. I found that in the previous set-up it was lower than the tip of the glass tube by about 2 mm. Lower meaning hitting too much coil and not directly mixing with the vapor stream shooting out of the tube. Its not a lot of distance but this is a game of millimeters, so I did two things. I grinded the glass tube down. It came out to ~5mm in height, and then I placed an additional o-ring on the atty base to effectively raise the airhole ~1.5mm above the tip of the glass tube. I was going to grind the tube further but I want to maintain room for at least a 6 wrap of 28g. I also replace the mini-wicks (the channels created by the mini-wick were just a nidus for gunk build-up) with an additional 30mm of SS wrap to build out the core wick for the AGA hole to fill the ID of the glass tube. So I now have a 2.5 mm core wick built out to ~3.5 to 4mm to fill the glass tube snugly.
I was able to used the same coil as before; I just twisted the positive pole nuts lower and tighten the coil a bit on the positive post to compressed the coil further. Not sure if I lost some resistance because I tighten the coil or I lost a turn of the coil because it grounded to the base, but I was able to get a solid 1.7ohm coil resistance.
I believe this set up now meets coil-on-wick quality. Heat up time is still an issue, but may be solved with FQ or thinner Pyrex tubing. That cheap fuse glass has not shown any signs of stress or deformation so far.( I am only experimenting here and not using this as a daily
vape) I believe the even heat distribution of 28g will be improved by the flat wire posted by BJ43. That and very tightly wound
coils should minimize thermal stress to any glass substrate.
Here is a pic of the revised setup. For AGA genny modders, note the tip of the glass tube is about the height of that useless protruding negative post.
