Well I thought I had it made with the shredded PTB and said I wouldn't use anything else until dis-satisfied with the PTB.
The PTB worked well with juices with a PG base. The wicking was good and kept my atty wet. That was until I started mixing to a ratio of 75/25.
Iniatially the end of the PTB would only show a small depression (straight PG mix). One would notice a decrease in vapour production and simply top off, all was well.
When increasing the viscosity of the mix with VG for a better vapour production, the liquid did not flow as well. This would be evidenced with a decrase in vapour. Upon removing the cart from the atty to top off, one couldn't fail to notice that where once there was a slight depression, now was a hole so to speak. When slightly pulling out the the PTB to "fluff" it out a little, I could feel a resistance in the material. This resistance was deemed to be the begining of the layers starting to "weld" together, for the lack of a better word. Ummmm...
Having read the forums etc... and seen that I did not vape like a manic so to speak e.g 45-60 minute sessions vice 5-8 good hits every 15-20 minutes, it became apparent what the problem was. Although I would top off after every session or two, (fresh cart) the fusion of the layers was always apparent caused by the heat of the atty, although I never vaped to the battery cut off or tasted burnt vapout etc...
I was told this was normal and to just fluff the ends up with a needle. Well that only partially worked, and would exacerbate the fusion problem even more, because of the finer strands of PTB.
I tried the hole in the condom etc... that one didn't work for me, I think I wasn't using a big enough straw as it remained round.
The other thing I noticed with the PTB mod as HP stated, you always had liquid remaining in the filler regardless what was used, so it was never good to the last drop

... which led me to drip more and more (not that there is anything wrong with that)
So this morning I decided to give Ping's mod a whirl, I'm impressed.
I started out with a fresh piece of polyfill from an unused cart, and cut a piece about 1/4 sq. Filled the cart up with 16 drops, and placed the plug in gently with tweezers just to get it in, and then gently tucking it in to bed with a toothpick. Toped off the cart with 3-4 drops and assembled it to the atty. Been vaping on it for the last 30 minutes or so, rather heavily (morning vape) while I formulate my reply.
I pulled off the cart every now and again. I have not notice any leakage, the small depression I was used to observng with the shredded PTB mod was once again apparent, and the batting appreared saturated. What will happen when I go to top off remains to be seen, but so far so good.
What conclusions have I drawn?
- I have been vaping now solid on my 510 and PT for a week. To date it has been the only device that has gotten me off analogs completly;
- I have yet to get a burnt taste that I hear folks mentioning all the time. However I believe some of this is caused by over vaping and inadequate wicking of the batting used (regardless of what that material is;
- I have tried the TB mod - dismissed that within 10 minutes after trying the PTB;
- When reading all that is available on the forums, everyone was after a mod that outside of putting our attys on permanent drip from a sytem (read IV), nothing seemed to work; and
- Nobody IMHO was addressing what appeared to me as the real problem - liquid viscosity.
I like this mod, it is designed by readily available material that was being tossed out. It follows the KISS principle. Outside of needing a pair of scissors and a toothpick or two (to use as chopsticks), requires no extra outlay of cash or the procurement of tools/fancy devices.
The mod makes perfect sense, as long as the plug remains just snug, one can easily see that it is indeed a modification that will not only envelop the bridge of the atty, but maintain the atty moist. It has now been an hour and have not have to top off like with the PTB, and there is no evidence of fusion. WTG HP and thank you.