Firstly, I agree with @BadBert about dry hits. When non-TC I find it a little easier to detect an impending dry hit and the first many of them on a given wick are not as harsh as cotton. Like anything else though, after so many dry hits hashness comes up and flavor gets nasty.
Due to technical difficulties and laziness, this is now clearly going to be a multi-part thread with just one build tonight, posted from my phone, but I invite anyone with a hemp wick build to post in here. Why not use the knowledge of the collective? I make no claims to knowing what the hell I am doing. I've been building tanks now for only a few months.
Anyway, my best tank for flavor is the worst to build, which is the Youde Bellus. She needs a fresh build so I can finally try out @Whiterose0818 MF honeydew.
First thing, I have only tried one brand of hemp, it is called Green Remedy and a bag shipped from Amazon is going to set you back $15.
I choose the diameter of my coil to hold enough hemp to clog the channels on whatever tank I am using. Hemp is not fluffy like cotton, so coil size also affect the resistance to flooding because it determines the size of the wicks you can use. The mechanical stiffness of your coils may determine how long it takes to build, as wimpy coils get tweaked due to the initial stiffness of the hemp. In any event, you can't just cram hemp into the coil, the upper limit is mechanical. But if it fits, it wicks. Tanks like the Bellus and Mutation XT are very prone to flooding, so you need the biggest coils that can fit to accommodate enough hemp to clog the channels.
The deck for the Bellus compared to the size of the channels makes it difficult to build a coil that wicks well, has enough resistance to fire, and doesn't short to the tank. I love 4x 30ga twisted Ti in this tank. I use 5 wraps on a 3mm jig. For the Bellus, I recommend doing everything mounted on the ohm meter, she shorts easily. By the time I tighten the tank up, my meter is reading 0.04 Ohms, but my DNA200 reads 0.9.
@SthrnMixer has posted about washing your hands prior to wicking, and I recommend that. I also recommend that those new to hemp to wet their wicks with flavored juice. I typically use a tobacco. These wicks have a significant woody flavor for the first few ml of juice. Some say it is terrible and/or strong. I can't tell you, but it's definitely there, will go away and IMO is worth suffering through.
I select a diameter that will just fit through my coil and cut a length about 2.5 times as long as I need. This is important as the wicking performance depends on the diameter of the bundle, so using the same bundle for both balances it out. Assuming you are civilized and have a coil jig, you should get maximum performance from a well balanced atty.
Wet the tip of the wick with a juice that might be good with an earthy, woody, and slightly floral flavor. I sometimes enjoy unflavored base, but I wouldn't break this in on a MF flavor if you know what I mean. Fold the tip over, twist it tight on use a twisting motion to force the hemp through the coil. Wet the whole coils worth of wick, fold to measure the length and cut.
Now, wet the tip of the remaining wick and guide it through the second coil. At this point, the longer you can let the hemp soak, the more pliable the fibers will become. That said, I recommend wetting the coils manually and firing, repeating until the smoke detectors are about to go off.
Once the room is all fogged over, work your wicks into the channels. The Bellus is a naughty one, so I usually have to put the tank on and off many times to get wicks that fit, while the tank is "clicked" onto the deck, without shorting. I do it all on my Ohm meter. If the wicks keep forcing your build to short, due to the stiffness of the hemp, keep manually wetting and firing and manipulating on the Ohm meter. Eventually the wick is as supple as cotton, but it is far from that for the first few hours soaking. I am not sure how long it takes, but eventually they will look like those shown below on my Billow V2, which has seen daily, multi-fill use for the last several weeks and still wicks and tastes great.
I have a picture of the thick, dense clouds this Bellus chucks. It is not a leaf blower like the TFV4, but the clouds are dripper dense. On TC, the flavor of this tank rivals my Plume Veil with a big chimney on it. I've posted elsewhere that built with Ti/hemp and on TC, the flavor is just dirty it is so good.
This has taken a few hours more than I had anticipated due to difficulties with getting all this pictures and the edits to save. I am not even sure now if it reads coherently as I have cut and pasted so many times. I will do another writeup on another build. I'll throw out that I have the following atomizers,the last two are in the mail: TFV4 (tf-r2), Advken Ohm ega, OBS Crius, Mutation XT, Aromamizer and Goblin mini. If you want me to build one of those throw out a request, for the last two please throw out a coil build too as I have not even seen one personally yet.
I hope this answers most questions, but if I missed anything or you'd like any further information just let me know. I apologize if you got any of the intermediate machinations of this post. . .it was pretty painful to get on the site for some reason.