Best Wicking Material

Find the biggest tube that will go through the hole. Put the downstream end into a pot that never empties, at least a couple of inches below. It will almost certainly wick through a straw that small, if not try a size smaller.

That would be a great solution, however I didn't give you the entire story. The water is not normally there and a pot is not an option. Think sampling water off a floor.

there are plenty of leak detectors out there, but why not. As you look at the physics involved, as implied by the first comment, you need continuity. You need to have enough liquid to wick all of the way up the wick to your detection scheme. So it wont be just a drop or two. You can calculate it given your dimensions. But you are asking for a wick. Play with cotton, or polypropolene (different wicking action). Watman, which makes laboratory filters, has several filters that will do the job - buy a box and start playing.

That's what we used before discovering the PTB mesh, it works good and can be found in woven and rope

Here's a discussion on the different Silicon and Fiberglass wicking material: http://www.e-cigarette-forum.com/forum/atomizer-mods/129327-wick-material-question.html and it all leads to MSC http://www1.mscdirect.com/Sleeve-Packing/Gasketing-&-Packaging/Raw-Materials/s0000001902.HTML

P-green and Smeaton are correct, something that small will be using the capilllary action of a small tube (fiberglass has the same properties), your real problem is if this is going to be an on and off liquid source he tube will evaporate and any residue will clog the small hole rather quickly.

Hi - I've worked on rising damp for some time (I know, must be slightly mad!) and the property you are looking for is "sorptivity". This dictates the rate of flow - you should be able to look up values for different materials. Generally I'd avoid something hydrophobic like PP and go for a cellulose type material or a silicate mineral type.

Would be worth you looking at the Lucas-Washburn eqn.

Sorry bit techy!

A narrow strip of Bounty paper towel,wound into a cylinder shape.

Surface tension is near 0.03N/m for water to clean metallic surfaces.

So try a bunch of capillary tubes. These have much more free cross section than paralelled glass-fibers or wires.

Calculate the suction height from balancing gravity against capillarity.

Then you get the allowed diameter of the capillary.

The bigger the better for flow rate but the worse for suction.

So the best solution would be paralleling thin metallic plates in a distance as calculated for the capillaries. But this is difficult to produce.

I tried a simplified approach for low flow rates: deep parallel scratches in a metallic surface. In reality V-grooves, these should be sharp to near 1µm at the bottom!

RHABE

Can you create a slight suction at the outlet? A cooling fan trying to draw air out of a nearly-sealed cabinet could be used to lower the pressure by a fraction of an in-H2O, which would help draw the water through whatever medium you choose. A larger fan or blower could be used to lower the interior pressure as much as you need while still moving enough air for cooling.

I'm involved in building Electric Cigarettes and we're always looking for wicking material to pull the "juice" up to a heated coil. Regular Silicon braded rope has worked the best in contact with the hot coil BUT we have discovered something new for wicking the juice up the silicon that works much better: it's the material Lipton Pyramid TeaBags (we just call it PTB) are made of, some kind of Nylon mesh and wicks significantly better than anything else everyone has tried. And we've tried everything, to improve the vapor production of these devices, and for wicking nothing works faster and better than PTB material, wish I could tell you what it is, we just empty the bags and use them. Before we found PTB we used a lot of aquarium filter foam sleeves and micron cartridges, H.O.T. makes a blue product that worked the best.

Just got a post at http://www.e-cigarette-forum.com/forum/cartomizer-issues/129229-new-royalsmokers-c-e2-r4-review-tips-info-help-video-108.html and they say the PTB's is: thermoplastic polamide Nylon and gave me this link http://www.ptsllc.com/nylon_intro.htm

Steam locomotives use worsted wool. Just buy a ball from a good haberdasher and weave several strands into a wick of whatever size and shape are required.