Heatpipe wick structures - a follow up.

It's a new day and my electrolysis experiment has been going for quite a while now. Unfortunately it's not gonna work out as I hoped it would for the sole reason that it's too slow and achieving a uniform layer of copper crystals is not as easy a I had anticipated. Therefore I decided to look at the more conventional methods of creating wick structures as well as a few more interpretations of my own.
For a my wick I need it to be easy to make out of materials readily available to me. Previous experiments indicate that I need my wick to be rather dense and very close to my tube surface in order to achieve best performance. I started out with some plain copper wire that I stripped and wound around a steel shaft.

I tried to wind it as flat as possible and I also wound it in two layers, each winding going in the opposite direction. This was to decrease the possibility of it coming undone since I've had it happen to me before. This wick design showed signs of ethanol up to the 35mm mark, which was not bad, about as much as the braided shielding from the old tech I used before. One thing to note is that the fluid reached highest where the wick was touching the tube and considering how troublesome it was to get this wick in and the fact that it takes some time to lay each strand flat makes this one of the less preferable options. It also has a high thermal mass, which is not great considering my next experiment. You'll see more of that in the near future.
Keeping in mind that thinner, more densely packed strands of copper would be better at sucking up my working fluid I went to my box of cables and wires to look for something and found a short length of some rather thick speaker wire. The speaker wire consisted of seven groups of multiple thin copper strands bundled together and served as the perfect contender.

 I then wound each bundle around my steel shaft and stuffed the whole thing in my acrylic tube. I then pulled the steel shaft out and my wick was ready to be tested.

With this wick my ethanol reached a height of 40mm. That's some pretty good performance if it weren't for one thing. That thing being that this wick is too thick and wouldn't be very good at letting the vaporized fluid pass through it to the center of my heatpipe. Considering this wick is far from ideal I went looking for better options. That's when with the corner of my eye I caught some shielded cable. It was the HV wire from a flyback transformer from an old TV.

I quickly ripped the insulation off then took the braided shielding off the wire and put it in my acrylic tube.

This braided shielding was not ideal since it was not dense enough, although I think it would be perfect in thinner heatpipes. In my test setup as a wick this achieved 25mm height. I might test this with some thinner heatpipes but I'm not sure about that because I don't have much of this HV cable. Because of that I went looking for more cable with braided shielding, preferably something with a denser weave.
I quickly found some cable that had a bunch of little silver strands coming out the end.

Bingo

The braid in this shielding was much denser than in the HV cable, which is exactly what I wanted. Didn't take long before this braided shielding was in my test tube getting soaked with ethanol. In my test setup this managed a height of 35mm, which is not the best but is a great result considering how thin and light this braided shielding is. That and the fact that I have quite a bit of this cable makes this the perfect option for my further experiments.
I also tried a little more experimenting with foil based wick. Since Al foil was a little too thin and fragile I took some nickel foil and creased it length wise with a blade from my box cutter. This only achieved 20mm.

This was quite a bother to get made, that's not considering the fat that I would still have to make holes in it for the fluid vapor to escape through. And since I have already chosen what I'll be using for my heatpipes made it easy to dismiss this concept.
That's it for today as far as heatpipe wick structures are considered but while I had some time I managed to do some experiments with thermocouples, more about that in my next post.
Thanks for reading.