Thought I'd offer up my efforts at making my new RTAs work for me.
This is not for those who direct lung hit. Nor is it for those who are happy with open airy draws on their atties.
I like a tightish MTL draw on my vape. I loved the draw in the Kayfun Lites and would still be using them if I could easily make them handle high VG juices. (I've tried going gorilla with dremels but failed to achieve reliable consistant results).
I've been happily using an older model rebuildable atties from UD for a good long while now but since they no longer seem to be making them, I've been looking out for suitable long term replacements.
In my playing around I've found that one critical dimension that affects a proper MTL draw for me and that is the size of the air tube directly under the coil assembly. Many/most modern atties have this air tube way too big for me. Example - the Lemo 1 measures about 3.5 mm diameter, whilst the Kayfun Lite measures about 1.7 mm or less. My current atty of choice measures 2 mm. Closing down the outside air flow control doesn't achieve the same result in the quality of draw and vape for me. Perhaps it is because of air speed thro that restricted air tube ... donno. Just that I knew I wanted a new atty that provided a draw that suited me and to do that it would have to include a small air tube under the coil.
When I read long forum threads about the Roxy Merlin by Augvape I knew it wouldn't suit me as shipped because it's air tube was 3.5 mm. BUT I also knew they shipped (in the box) an airflow reducer which reduced that air tube down to around 2.5 mm. I knew from experience that would still be too big for me BUT what got my attention was that the attie's air tube was threaded. Specifically, it used a 4 by 0.5 mm thread = metric M4 fine. And that gave me a clue.
So I hunted around for "machine screws" I could rework into a replacement air reducing sleeve. I found these polycarbinate M4 screws at a local Electronic's retailer :
linky I also purchased some regular metal M4 nuts that'd thread onto those screws from the same place.
First - the RTA itself:
linky Courtesy of FT, pics of the atty deck itself with the reducer inplace (rhs of this pic):
As expected, I found the polycarbinate machine screws threaded properly into the deck, BUT
* The screw head was too thick
* The screw head was too big in diameter
* The screw was too long
* The screw required a hole drilled thro it.
So - off to the shed!
First a general comment - these are polycarbinate, not metal. They are soft. If you are contemplating trying something like this yourself - EASY DOES IT with any machining. Drill slowly - very very slowly. Machine sand slowly. The stuff melts when worked too hard and then you'll find the screw sagging and twisting out of shape. That is why I bought those nuts - I used them to support the screw as much as I could whilst working with them. Also, the metal nuts could re-cut the thread after I cut the screw to length.
Also - I did give consideration to the material used, since it was in my "vape path". Health and safety of what I'm inhaling - but I immediatly thought we also have tanks made of polycarbinate - so I'm assuming that means I'm safe doing this... *shrug* still gotta be better than smoking!
I mounted the screw into a drill:
I sanded the top of the screw head to reduce the thickness:
I sanded the edge of the screw head to reduce the diameter
I threaded nuts on the screw to support it when I cut it to length
I then drilled the screw with a 2.00 mm drill bit:
To end up with a final result. In these pics you can see one I've made (I made several - some with a 2mm, others with a 1.5 mm center air hole), a coupla 4 mm nuts together with an original factory supplied reducer. Yep - mine look bigger - but they fit and work well.
I've no shots of the new one in, coiled up and working. I've been vaping with it for 2 - 3 weeks and it MTL restricted draws just like I wanted. I've the option to change that draw to suite me - just by drilling different sized holes.
All that said - apparently there is a "mini" version of this atty on the cards, and, apparently it will include two smaller air reducers in the box... 1.6 and 1.2... perfect for those of us who do like that tight draw.
As for the rest of the RTA? It's OK. About 4 mm capacity, room for monster coil builds if that's your thing. Single center coil position - although some have built two coils one ABOVE the other. Wicks like crazy. I'm pushing a heady 18 watts (!) and I need to significantly close down the juice flow control. It'll easily push much, much higher than my humble needs and, without the supplied air reducer allow higher watts direct to lung if that's your thing. It seems OK flavour wise - but I'm not your person to offer flavour advice.
All that said - I still prefer my AGA-T5s. But these certainly make for a suitable alternative.