D-ice / LN2 "semi-solid" design suggestions

[Epox4life]

10lbs isnt enough, id say buy at least 25lbs, maybe even more if you will have a cpu and gpu pot.

 

[NoL]

10lbs isn't enough? How long do you bench for!
I bench 2-3 hours and 10lbs is more than enough, it leaves me about 2-3 lbs at the end to play with.

 

[Joe Camel]

hummmm ok.

the theory was a few "fingers" of aluminum (1/4" OD rod) welded into the base and pointing up. although this will work, too many and it will become difficult to pack pellets around/between them.

what about 1x in the center about 2" tall and then short "nubs" of about 1/2" (maybe 5x) in a circle around the one center tall one?


this is for a CPU "Plate-n-Pipe" design.

 

[NoL]

Well that is the point of acetone, to create max surface area at the bottom. Though people don't recommend using a lot of acetone as it will mostly imho affect pulldown times, if you must I've used a max of 5 shots of acetone in my old aluminum mousepot (now in Waffles hands) and never seen a temperature difference after the first 10 minutes.

 

[g0dM@n]

i have a feeling that it's almost not even worth doing that, JC...

i mean, does it make that much of a difference to have the "fingers"... i like to call em "jets" like the storm's were called...

Well that is the point of acetone, to create max surface area at the bottom. Though people don't recommend using a lot of acetone as it will mostly imho affect pulldown times, if you must I've used a max of 5 shots of acetone in my old aluminum mousepot (now in Waffles hands) and never seen a temperature difference after the first 10 minutes.

lol 5 shots...

 

[Gautam]

Rich, from what little K|ngp|n has let out of the bag about his super secret pot design, it seems like he has a bar in the center, right above the core as in your idea. He said that picking the right height is crucial, and that's one secret he won't let go. My Chilly1 container has a bar in the center, about 2" tall and I think 3/8" in diameter. So basically you're heading down the right path.

However, the more popular design these days seem to be jets on the base, ranging from 1/4" to 1/2", so obviously a lot bigger than on waterblocks, but the same concept.

As for which one does better, I have no idea but like I said I think you're definitely on the right track.

 

[Epox4life]

JC: Rod in the center and smaller ones around it sounds good.

10lbs isn't enough? How long do you bench for!
I bench 2-3 hours and 10lbs is more than enough, it leaves me about 2-3 lbs at the end to play with.

NoL: Not much of an overclocker are you?
Bench session for me last all day like 8+ hours with 25lbs of pellets, a cedar mill 651 @ 1.7v+ will use most of it.

 

[Gautam]

i have a feeling that it's almost not even worth doing that...

i mean, does it make that much of a difference to have that?

The acetone is absolutely worth it, and different levels do perform quite differently depending on the design of the container. My chilly1 container has a bar in the center as I said. A friend and I did our best to test different levels, and got the lowest temps (by over 5 degrees) with it filled up to the top of the bar.

 

[g0dM@n]

The acetone is absolutely worth it, and different levels do perform quite differently depending on the design of the container. My chilly1 container has a bar in the center as I said. A friend and I did our best to test different levels, and got the lowest temps (by over 5 degrees) with it filled up to the top of the bar.

i wasn't speaking of the acetone... was speaking of the "fingers" (jets)...

how high is that "bar"? pix plz!!!

 

[Epox4life]

how high is that "bar"? pix plz!!!

My Chilly1 container has a bar in the center, about 2" tall and I think 3/8" in diameter. So basically you're heading down the right path.

 

[Joe Camel]

jets (to me) are holes drilled into, but not through, the base.
fingers/pins protrude out of the base.

so king's only has 1x bar direct in middle huh.... as much as i like the smaller ones around the sides, it will restrict the ICE from coming in contact with the base and thus (i assume) not a good plan.

mid-pin must not be taller than the Ice-mix.... think ill go for 1/4" below the level of the slush and assume 2" slush level, so 1.75" above base plate.


ya?

 

[Gautam]

i wasn't speaking of the acetone... was speaking of the "fingers" (jets)...

how high is that "bar"? pix plz!!!

Oh sure, go ahead and make a ninja edit AFTER I post. Thanks for making me look bad.

The bar should be worthwhile as well as I stated in my earlier post. Having mass directly above the core helps stabilize temps. I'll snap a pic of the inside of my container when I get home.

The jets drilled into the base are more popular IMHO because its much easier to drill a couple of dimples than to weld a bar.

JC, all the dimensions sound spot on to me and I think what you've got in mind should work very well.

K|ngp|n said he has a bar in the middle, but he never said that's all he's got. More bars, jets, who knows?

One thing to keep in mind about the base is that just like in heatsink and waterblock design, there will be a happy medium as far as mass goes. More mass = more stable temps, but higher minimum temp, with less mass being the opposite.

The issue of getting the dry ice to the right places in the base is why powdered DI is strictly speaking the best. Optimally, get a block of DI, which will last the longest, and smash pieces of it into powder as you need it. It really is the optimal way to do it but I'm lazy and always go with pellets myself.

But for more complex base designs, powder should help quite a bit, and I think for my future runs I'll finally switch to it. Helps in controlling temps if needed as well.

 

[Joe Camel]

jets/holes/divots increase surface area but reduce mass...

fingers/pins increase both.



the further away the slush is from the CPU, the higher the idle temps; closer=lower
-but-
reducing mass to lower idle temps will kill load capacity.

balancing act


single pin in center surrounded by (guess) 5x jets .... best of both?

.

 

[Gautam]

Yeah, jets definitely help a lot in waterblocks as far as increasing turbulence, but I'm not sure how much that would help in this application, if at all?

But plenty seem to be doing it.

 

[g0dM@n]

blah blah blah

lol... man my memory has gone to poop!

sorry... trying to keep up with the thread while i finish up some work... i'm a badboy...

and that wasn't ninja action gautam... i just always hit the quickedit without looking.

 

[Joe Camel]

Yeah, jets definitely help a lot in waterblocks as far as increasing turbulence, but I'm not sure how much that would help in this application, if at all?

But plenty seem to be doing it.

its VERY easy and does increase surface area

and if my above theory is right, it could lower (idle) temps.


(turbulence is not really involved here really as we have a "standing" liquid)

 

[Epox4life]

Your memory will get even worse after you do some dry ice sessions.

I think we need someone that has taken a course in "Advanced Thermodynamics Engineering" lol.

 

[Gautam]

Ahhh....another edit...but that's in fact exactly what I was starting to think, bar with jets. Sounds yummy...this is gonna perform real well I bet.

 

[Joe Camel]

hummm im sure glad were all doing some good "WORK" while @ work huh

if our boss's knew what we were doing all day

-------

anyway, i think thats the plan, single 1.75" tall x 1/4" OD rod in the middle and im thinking 5x 3/8" OD "jets" drilled into the 9.2mm thick base plate; down to (?) 1/4" thick




EDIT: ya, i edit like crazy (too) sorry
.

 

[NoL]

Heh I'm out of school at 2 so speak for yourselves.