Now I’m wondering if rayon is the one that shrinks…one does. Hrm. In any event my comment was directed toward muting. I’d still wick it looser if it’s muting.
I’ll still stand behind rayon not having any flavor in my testing , I’ve never tasted it anyway. . .But I can’t taste wire either unless it’s dirty wire. The only thing I can reliably taste is cotton, ken doh gold being the best cotton of tried.
That is definitely the ‘everything you ever wanted to know about rayon wicking’ thread.
JeremyR did an outstanding job. Lots of info there.
I purchased Graham #44060 from Sally Beauty about a year and a half ago for under $20 including shipping (there was a promotion and free shipping at the time). I notice that they no longer have this product number (it is 100% pure Rayon Fibers) but do see it available on Amazon for a few dollars more. https://www.amazon.com/Graham-CelluCotton-Beauty-Rayon-Fibers/dp/B00PBF8PAG/ref=sr_1_fkmr0_1_a_it?ie=UTF8&qid=1506178318&sr=8-1-fkmr0&keywords=44060+graham+cell
The product is exceptional for flavor and nicotine hit and lasts much longer while remaining clean better than any cotton I have ever used. There is a learning curve to wicking it, I have found that you need to wick it much tighter than organic cotton as it tends to shrink as opposed to swelling like cotton when wet. That said if I am in a hurry to wick, I still use cotton on occasion. All said the hype is real…as with any wick what you don’t want to do is dry hit the stuff…it is awful…although not any worse than cotton.
Note: Found it on Ebay (with free shipping) https://www.ebay.com/p/Graham-Cellucotton-Beauty-Coil-500ft-100-Rayon-Fibers-44060/1338388232?iid=182737371269#UserReviews
I picked up a 500 ft / 44060 box at about the same time. I was fortunate that there was a Sally Beauty store a few miles from me. Walked in, grabbed it off the shelf, paid somewhere around $15 and walked out.
It’s not like you need a constant source for the stuff. One box and you (and a couple of friends) are set for life. 
check that …one box will last about a lifetime!
I end up cutting off a foot or so, then splitting that down the middle, lengthwise, to get the thickness that works for me, so that 500 ft box turns out to be about 1000 ft!
Yeah, I cut about a foot or so and put it in a baggie…that generally lasts me over a month and I am not too careful about waste & I re-wick frequently.
the european sources i linked to are 1kg that should be about 2.2 lb should be enough to last a life time aswell
I just finished giving 5 tanks the once over. Disassembly, USC bath, blow out with compressed air, re-coil, & re-wick. I used 6 inches of rayon, including the trimmed scraps, and that was a 6 inch piece that was split down the middle. Doing the math, if I did that once a week, (which I don’t) that’s roughly 38 years worth in a 500 ft box. I’m 63. I’ll never see the end of that box…lol
never give up hope
Buy it once buy it for life?
I started using Rayon early ‘16… mainly because I’m a 100% NET juice user. 
Changing my wick and doing a coil burn is a daily routine for me. I had to have a wick which needed, virtually, no break in time and was inexpensive. Plus, the wick needed to resist a dry hit scenario, since I vape on Power Mode 24/7/365 and use a Kayfun V5, steel tank option, most of the time. Rayon punched my ticket. 
I was in a little rayon discussion, over on ECF (not JeremyR’s huge thread) and learned a tip on how to prepare rayon for wicking. She mentioned ‘drafting’. The technique is used in preparing wool, to go on a spinning wheel, to make yarn. The purpose of drafting the wool, is to stretch it a bit, which helps get the fibers lined up in the same direction. It was mentioned that it improved the capillary action. There wasn’t any scientific proof, but it made sense to me that it could work better than just having the fibers going in random directions.
Here’s a link that provides a visual of the process. The meat & potatoes of the video starts at the 1:00 min mark, and goes to about the 2:30 min mark.
The wool fibers, as shown in the video are about 6 inches long. Rayon fibers are much shorter, but the same process applies. If you notice how she stretches the wool. it thins a bit, as the fibers line up. She holds the wool 10 or 12 inches apart. With rayon, I hold the rayon between thumb & index finger, 2 or 3 inches apart, and just give it a gentle tug in opposite directions. You can feel the fibers slip a little (gentle tugs only, or you’ll just pull it apart). It sounds more complicated than it is, and perhaps it’s splitting hairs (pun intended) for our purposes, but I just do it as part of my rayon wicking process now. I can’t say I notice any drastic improvement, but the concept made sense. It only adds a couple of seconds to the wicking process.
Maybe useful, maybe goofy. Both have value!
I’ve only used rayon twice (so far), first in a Griffin mini about 5 or 6 days ago, then this morning I placed it in a Griffin 25. Prior to this I was using cotton, kendo… then a month or so ago, cotton bacon II. Both of these presented a off taste (to me) for a few tanks then settled out. Now with the rayon that @Cutlass92 so graciously provided to me to try I am still getting a slightly off taste for a tank, and it seems as if the vape is very dry as opposed to a normal vape of the juice. This dryness also dissipates after a tank or two. Basically pretty much the same issues as with cotton, possibly not as much as cotton, but that jury is still out. @Cutlass92 suggested that I used a tighter strand than with cotton and this seems to have worked nicely so far, no dry hits nor burnt tastes.
I don’t know where or what brand of rayon @Cutlass92 provided to me, but it seems to be “rope” and I would probably purchase it.
Celucotton is what I sent you tut, here is a link!
Graham Professional Cellucotton Beauty Coil (Rayon fiber) https://www.amazon.com/dp/B018IYY3I4/ref=cm_sw_r_cp_api_kAUXzb9WW3CMM
I think we switched about the same time, and had a rayon thread going, that is buried in the vault somewhere. I’m strictly power too, but I can see my juice, unlike the steel tank! I use the plastic middle section in my Kayfuns. I know rayon dry hits are much more forgiving. Even with the aid of visual juice level, I’ve started to taste the scorch of a tank running dry.
I shouldn’t admit this, but about a week ago, I had 2 tanks going on my desk. I was switching back and forth while I was balancing the checkbook and paying bills online, so my attention was split. I wasn’t paying attention and one of the tanks started to go dry. I just grabbed the other tank, and went on with the bill paying. I’ll be damned if I didn’t grab that empty tank 3 more times, while I was sitting here! I finally said this has got to stop, and TOOK the thing over to the rebuild bench, out of reach, so my dumb ass would stop hitting it!
Getting old sucks…
Yup… me as well; I feel like it helps with the capillary action of the juce flow. But heck… my base mix is 60PG/40VG, so it’s gonna flow through most any wick at a speedy rate.
Thanks to @therabidweasel, I’ll be experiencing some Hemp soon… just for fun. If there is a lot of break in time on the Hemp, I might have an issue there. I dare say, most of my NET liquids will probably mask any woody flavor which comes from the Hemp… we shall see! 
Mine came in, and I’m a little unsure of how to wick with rayon after I watched a you tube vid on wicking with rayon please check out the video and I would appreciate your comments / suggestions This guy makes it so complicated
I don’t thin my wicks, I did when I started using rayon but out of laziness and from personal experience I have found no discernible difference between thinned tails and unthinned tails. What are you going to try it in first? I might have that rda rdta and I could snap some pics to help you out.
I’ve been using rayon for about a week or so now and I’ve found the same thing. It doesn’t need to be thinned out any more than cotton. I wick with it exactly the same as I do with Kendo Gold. I’m leaning towards Rayon being my wicking material of choice, I think it does everything cotton does but slightly better.