My attempts so far on removing the powder from the c8ors can simply be expressed in the following meme format:

Day 1

So I asked Eleven what the engineers did the last time:

So I was wondering how I could line that up, since a standard vacuum didn't sound like the best idea, and then I saw syringe nozzles as a recommendation in AliExpress:

So I went and used the syringe and tube my uni just happens to have:

As you can see, the syringe is full of water. This is because I wasn't able to generate sufficient pressure by pumping air into the c8or and the atmosphere generated even less when suction was used. 

The only win I was able to get was to unblock ch8. All other channels stayed blocked, but water did drip through them.

Day 2

The idea was to come in from the other side.

All I learned was that the copper gasket 100% works without any uncertainty or doubt. I was able to apply maximum water pressures on all channels and the plunger didn't budge. It also means that I took the correct call and not just tried to extrude the powder out with plastic, because it wouldn't've displaced out the powder either.

I tried the needles that also happened to exist, wondering if the powder just needed an escape route, but still no success.

Looking through the macro lens of my phone, I could see that the other, dry c8or still had visible powder so I tried the classical resistor-wire pickaxe-floss method and all this dust came out:

Thus, I was wondering if the dust needed to be agitated. "Hm, what I need is maybe like an ultrasonic cleaner or something. Are any of these machines [around me] one?", I thought.

As instructed by the control panel, I looked up and read through the instructions and then put the wet c8or in. My strategy here is that I keep one of the c8ors dry, because it's possible that the water surface tension could "dough-ify" the powder.

I tried both upside down and rightside up orientations, and did a few sub-5 minute attempts before letting it run for 2 rounds of 10 minutes at 40C water. When it was finished, I'd put it on a paper towel and a small amount of powder would come out:

Meanwhile, this is all the powder that came out of the pickaxe floss method:

 Day 3

The strategy was to find and strip some stiff wire and mine inside the dry c8or while the wet c8or was inside the ultrasonic cleaner for 23 minutes at a time at 45C. 

This is what I got from 2 ultrasonic rounds:

This is what I got by mining in the same timeframe:

Lastly, I put a drop of water on the dust to confirm that the powder does stick together when wet:

Future Work

My next strategy is to boil or superheat the wet Coaxial8or. Since it seems that the water can barely weave through the powder, the idea is for it to act kind of like TNT by causing it to turn into steam and expand from the inside. 

On a similar vein, I could block the channels with water already in there and freeze it, potentially generating more pressures than what I can physically accomplish with a syringe.