Scratch Build – In Progress The Mineral Oil PC - 3/24/2011 - More leaks :(

Thanks

I am a Electrical Engineering co-op (intern-ish) at a major power utility. I went to the shop where we service broken and old transformers. Guess what transformers are filled with.... mineral oil!


We have a gigantic tank of the stuff. I wasn't allowed to steal any It would be nice to use the machine shop to construct my case; there's a bunch of nice metal working machines.

 

you would be the one to know this, but i've heard many times that the oil in transformers can actually become radioactive with use. great work so far on everything.

 

What kind of blade do you use in that miter saw? I hate using a hacksaw and making crooked cuts.

As for the hole saw, is it a bi-metal hole saw? If not use one. And either way, with suck thick metal you should use cutting fluid. I use a spray stuff called "Fluid Film". Works VERY good for tapping, cutting and drilling.

Frame definitely looks strong! Good work!

 

Meh, I've never heard that. I don't see how it would be possible either. Stuff just doesn't become radioactive for no reason. Are you sure you aren't thinking of the coal fly ash being radioactive? Most things dug out of the earth (like coal) have tiny trace amounts of radioactive materials in them. These trace amounts are pretty much undetectable and harmless until the material they're mixed with disappears. Such as fly ash left over after the burning of coal.

Thanks for the compliments.

I'm not sure. My dad made the comment that I better not dull his $60 blade. I do use cutting fluid when drilling the 3/4" holes through the bar stock and when tapping. Sure makes things easier.

Heh thanks, this thing will be able to support 5,000lbs of mineral oil when I'm done.

 

"Viscosity"?

"Deep Fried Chips"?

"Think Tank"?

 

Give it a name that will make your mom worry about the carpet- 'Professor Leakey.'
'Puddles'
I'd use the cutting oil with the hole saw too. They get really freaking hot.
@Talledega - That's pretty much what I was advising.

 

Make a quick video tour of the shop.

 

Nice Makita drill!

 

Nice shop! And excellent project too btw, really interesting and so far from what ive seen built to the highest quality!

Little tip for anyone and everyone who likes to mount fans on rads easily and still have some vibration dampening... use a silicone fan gasket between the fan frame and the radiator and you can still use screws to mount the fan, just don't tighten the screws too much... Quiet PC's silicone gaskets are our favourite for this.

Seriously tempted to subscribe to this... your craftsmanship is top notch!

Also, its nice to hear of someone else who is using Win 7 extensively at the moment, I have it running great on one of my own PCs and am extremely impressed with it so far, despite the usual beta version issues like lack of supported drivers and occasional hang ups

 

Thanks! If the fan hadn't come with the rubber nipples, I would have bought gaskets. I was eyeballing them at a few shops.

I'm loving Win 7 so far. I like being able to drag maximized windows and moving windows to the middle-top of the screen to maximize them. My only problem is there are no Windows 7 drivers for my Asus Xonar sound card. The Vista x64 drivers work just to get functionality, but none of the more special features work. That is; no surround sound, mic doesn't work, no stereo -> quad and the audio control panel doesn't work. TF2 has a strange quirk, when I close it, my monitors re-order themselves from 4,1,2,3 to 1,2,3,4. Besides that, everything seems great.

However my biggest gripe is still lack of support for multimonitor systems. The dragging of maximized windows is great and all, but the single monitor taskbar is pathetic. I shouldn't have to run 3rd party apps like UltraMon to get functionality that should be there in the first place. This was a serious omission in Vista and is inexcusable in Windows 7.

Hmmm, Viscosity seems pretty cool.

Yea, I like it a lot. It has a lot of power. Thanks for reading all of my posts! You and The boy 4rm oz are great.

 

good job so far! the feet look gorgeous!

 

Just doing some fun math while bored:

Heat capacity of air: 1.0035kJ/(kg*K)
Heat capacity of mineral oil: 1.966kJ/(kg*K)
Heat capacity of water: 4.184kJ/(kg*K)
Heat capacity of fluorinert: 1.014kj/(kg*K)
Quick definition: amount of heat required to raise 1kg of the substance 1C. You may notice that mineral oil is worse than water and hardly better than air!

Well, we're missing a little bit of important information.

Density of air: 1.2kg/m^3
Density of mineral oil: 800kg/m^3
Density of water: 998kg/m^3
Density of fluorinert: 1740kg/m^3
Quick definition: The weight of a cubic meter of the substance @ 20C.

Water may be more dense and have a higher heat capacity, but it is conductive (a topic on its own). Air is very light and has a lowish heat capacity.

If my tank was 1m^3, I'd be able to dump the following amount of energy into it before hitting 100C, starting at 20C
air: 96.34kJ = 27wh (watt-hours)
mineral oil: 125824kJ = 34951wh
water: 334051kJ = 92792wh
fluorinert: 141149 = 39208wh

So while water would be ideal, and fluorinert would cost thousands, we'll have to go for 3rd place; mineral oil.

If my tank was 100% insulated (no heat dissipation), contained 9 gallons (.034m^3) and the mineral oil started at 20C with the PC putting out 500w, it would take 62 minutes to hit 55C. Air would take 2.9 seconds.

 

Completed Lower Frame

Hurray! Update time! Summary of work since Saturday:




I finally completed all 4 feet. I gave in and made them all using the hole saw; they just come out so much better this way. They're all fairly close to the same size; no differences big enough to discern once they'll be in place at the bottom of the case.


All of the L brackets needed to complete the lower frame assembly.


The top portion of the lower frame all put together.


Decent macro shot of a corner.


Hole tapping fun.


Completed drilling and tapping the risers.


And then put it all together.




Close ups of some corners.


It's quite sturdy. I weigh 130lbs and it didn't flex at all.




Checking the spacing just to make sure I didn't make the frame too small!






Remember this?


Doing a few test cuts on a piece of scrap.


And now doing the cuts on the real thing.


From the other direction....




Checking the fit, looks good.


View of both cuts. When I did these cuts, I backed out the screws about 1/4" to make sure I didn't chop parts of them off. If my calculations were correct, I wouldn't have cut into any screws even if I didn't back them out, but I wanted to be sure.


Oh noes! The jig slipped! This piece is unsalvagable. I've already cut a new piece of bar stock to length and am preparing it to take the place of this one.

And that's where I stopped tonight. I'd once again like to thank Petra's Tech Shop, Danger Den and Crystalfontz for helping me out!

Thoughts?

 

How scary is cutting that? lol

 

You mean it's only supposed to happen in the Beta version!?

 

It's quite sturdy. I weigh 130lbs and it didn't flex at aaaaaaaaaaaargh!

How about "The Liquidator" for a name?

 

Those feet look awesome ( i mean the case feet, not yours, haha )

 

The feet look fantastic. Great work on the frame, very sturdy.

 

Lol, I made my dad do it. I wasn't confident enough. He has more experience with such things.

Haha I hope not. I expect the rest of the machine with the oil and all will weigh close to 100lbs. I'm debating whether or not I should add a support in the middle. I really don't want the longer pieces of aluminum to bend. The plexiglass tank will be sitting on top of the frame and if the aluminum bends, it will put stress on the acrylic joints of the tank.

Heh, thanks

Thank you sir!

 

nice job

well i think that the force will act at the side bar. the middle part of the joint will have minimal force acting. that is to say that the panel below are flat and able to stand the weight of the mineral oil.