Oil Dip

[Tostr4]

 

 

I made a case to submerge my desktop in thermal oil. Instead of the glass or plexi aquariums, I preferred a stainless steel case, because of thermal conductivity

 

With a few heatsinks attached to the side, I don't need any radiators or pumps

 

 

https://photos.app.goo.gl/STkZgdBR84dQWf8U6

 

Experiment conclusions:

 

- Leak test before placing it on a wooden floor !

 

- When I leave it folding@home for more than 2 days, temperatures stabilize at 45°C, and the front side heats up more than the rear underside. I threw in a small 12V drain pump with a piece of garden hose ( No, I'm not into esthetics) to even out the temperatures. 

 

-I wanted to keep all components under 60°C. GPU under load max 55°C; 10°C more then the oil temp. SSD's and RAM stay at oil temperature I suppose. I have no means of measuring them.

 

*Only the CPU cooling is a failure. Onder heavy load (2 days folding) I got to 83°C at 4.3Ghz. The cooler master fins are too close to each other, so the oil doens't pass trough. I am considering two options:

1: destroy the cooler master by cutting away 90% of the alu fins, and letting the oil make as much contact as possible directly with te heat pipes.

2: replace with a cheap AIO water cooler, where I dismount the radiator and use the integrated pump as a circulatory pump.

[Tostr4]

...and we're back. I'm sure you guys missed me. 

 

I tried option 2: CPU block with integrated pump. Not good. First you have to get the water-based coolant out of the pump, and then the oil in. In less than 5 seconds the pump blocked, and fried its motor wiring.
So I had to order another AIO and spent 2 days without desktop.

https://photos.app.goo.gl/iPmJYWwARjXtJAgm7
Second attemt went better. The pump ran on oil instead of water, but only very slowly. The oil proved too thic. Even at full 12V the flow rate remained too low. At idle I got 75°C, and you could watch the pump ramp up once the oil started heating, and the viscosity got better, but still far from satifactory. On load the CPU shot to 85°C 

 

So I went for option 1: the adaptation/destruction of the air cooler

https://photos.app.goo.gl/qfAw3NWPp8kFJbnZ6

Exposing the heat pipes as much as possible, to allow a better oil flow.

https://photos.app.goo.gl/evmmTBeLvidDaXfYA

I pierced one heat pipe in the process. Too bad. The copper tube wil still serve as a conduit.

https://photos.app.goo.gl/WM3nTQbXYoUkFyTe6

Back in the dip.

https://photos.app.goo.gl/MkLsU9yafdRcBBBV8

 

Oil at 19°C. Idle CPU at 28°C, After 30 minutes folding oil at 19,8; CPU 72°C. I was looking for a way too keep everything under 60°C, but I think I'm gonna have to learn to live with these results.

 

 

 

 

[Tostr4]

Update:

 

To keep oil temperatures below 40°C, I mounted a radiator with a gear pump to circulate the oil between reservoir and radiator.

The problem is that these gear pumps are quite loud. But I didn't even bother with membrane pumps, because the oil will at some point destroy the membrane. So I got a 12V engine oil transfer pump, and reduced its rpm, and noise with a DIY PWM controller.

 

The filter is quite important to prevent metallic pieces from the inside of the used and corroded radiator to get recirculated onto the mobo.

 

Next mod is replacing the poorly adapted CPU cooler by a 6-pipe stripped cheap cooler.

With the oil at 39-40°C, the CPU still stabilizes at 85-86°C. Enough to thermal throttle from 4,4 to 4,0 GHz. I would like the CPU below 80°C.

So I stripped all but 4 of the alu plates from around the heat pipes, to allow better oil flow around the pipes. I left a few, so I'm still able to attach a ventilator to increase oil flow, and to keep the pipes in their position.

 

 

I am getting some PerfCaps on GPU-Z (Vrel & Vop) that indicate that my PSU is further deteriorating. I allready destroyed the 12V to Molex by letting a transfer pump running too long, and eventually frying itself. The increase in power draw from te pump caused some instabilities on the 12V that powered the front mounted thermostat. And after a while it died alltogether.

So now the thermostat, exterior fans and pump run on a external 12V power supply.

 

But I'm considering replacing the cheap 450W PSU by a decent 650W. 

 

All in all, with the circulation pump temperatures while folding remain stable between 39 and 40°C (thermostat at 40°C; hysteresis 1°), so I think I'm ready for folding month beginning the 12th, even without the CPU-cooler and PSU replacement.

[Lachlancraw40]

Really cool build man loved all the pictures! Do you have a glass panel on the front of your case or acrylic? How did you seal that?

[Tostr4]

On 10/7/2020 at 1:13 AM, Lachlancraw40 said:

Really cool build man loved all the pictures! Do you have a glass panel on the front of your case or acrylic? How did you seal that?

Panel is acrylic. The seal is just plain Tec7 white glue. There are metal strips behind the acrylic with the bolts welded on, to be able to tighten the whole thing.

[Lachlancraw40]

5 hours ago, Tostr4 said:

Panel is acrylic. The seal is just plain Tec7 white glue. There are metal strips behind the acrylic with the bolts welded on, to be able to tighten the whole thing.

That’s pretty cool I was wondering why their were screws bolts around it.

[Tostr4]

19 hours ago, Lachlancraw40 said:

That’s pretty cool I was wondering why their were screws bolts around it.

As a matter of fact, there were only 3 on each side to begin with. Afterwards I realised that 3 might not be enough, so I added 2 more M6 screws on each side; but you cannot weld with the acrylic allready in place, so I had to drill them. Guess where we have leaks...

[A1200]

Wow!

[Lachlancraw40]

On 10/9/2020 at 12:54 PM, Tostr4 said:

Guess where we have leaks...

Lol rip

[Tostr4]

Allright. I mounted the 650W PSU and de stripped CPU cooler. I'm not much into RGB, but I kinda like the effect of the blue LED's on the CPU fan in the oil:

 

 

In numbers though: Oil at 40°C CPU 6 cores stress steady at around 70°C  ; +/ - 3 °C. I keep telling myself that this will have to suffice.