made a second #Rotor block
 

well, since this is the second try at #Rotor, let's just call it, umm... FC ;) anyway, here are pics.http://filebox.vt.edu/users/mkondel/...c/DSC00107.JPG http://filebox.vt.edu/users/mkondel/...c/DSC00109.JPG http://filebox.vt.edu/users/mkondel/...c/DSC00110.JPG http://filebox.vt.edu/users/mkondel/...c/DSC00111.JPG http://filebox.vt.edu/users/mkondel/...c/DSC00113.JPG http://filebox.vt.edu/users/mkondel/...c/DSC00114.JPG http://filebox.vt.edu/users/mkondel/...c/DSC00118.JPG http://filebox.vt.edu/users/mkondel/...c/DSC00120.JPG http://filebox.vt.edu/users/mkondel/...c/DSC00123.JPG http://filebox.vt.edu/users/mkondel/...c/DSC00125.JPG http://filebox.vt.edu/users/mkondel/...c/DSC00126.JPG http://filebox.vt.edu/users/mkondel/...c/DSC00129.JPG http://filebox.vt.edu/users/mkondel/...c/DSC00130.JPG http://filebox.vt.edu/users/mkondel/...c/DSC00132.JPG http://filebox.vt.edu/users/mkondel/...c/DSC00133.JPG

GOOP'ed the barbs and around the inside. waiting for the stuff to harden a little before sticking it in the loop.

NICE! see I told ya..... It ain't that hard.... :D

How long did that take you, start to finish? Looks Great!

thanks guys:D

how long did it take me? 9 hours: 6 hours to drill and tap, 3 hours to sand it down to a half assed lap job. why did it take me 6 hours to drill? because i have the cheapest, $90, drill press form sears. wood bits would get stuck, so i had to drill pilot holes all the way with a 3/32 bit and then go all the way up to 13/64 one by one. that's 8 rounds of drilling. but the first one is the worst because the bit gets stuck so easily. i tried cobalt and titanium bits, but those get stuck even more. i always used WD-40 on every hole to help it go.

what do you use to cool the copper down, while drilling ....
remember.... as the copper heat up, the hole will tend do shrink.... ya I know it's suppose to expand, but because the heat is so local to the hole, it tends to shrink first, until the heat works it's way out into the surrounding copper... What does this mean... it means that as the hole heats up, it tends to pinch the bit, and from there the getting stuck part.... try cooling it with water while you drill... see if it helps.

i realized that drilling had this effect with heat when i started making these blocks. what i do is i just drill about 2 lines of holes at a time and then let everything cool down while i dip the copper in a bowl or water. as the bit sizes get bigger, i dont have to do it anymore, just stop once in a while to wipe off the shavings and spray some more WD-40 in the holes.

also the faster i can go down, the less it will heat up, so i just try not to keep the bit at one stop for too long and kinda have to go up and down a few times on each hole.

this block, 45 load - 25 air = 20 dT, let's just say i get 80W, so that'll be C/W=0.25

http://filebox.vt.edu/users/mkondel/...r/DSC00084.JPG

now, the new block, 42.5 load - 26 air = 16.5 dT, that's C/W=0.21. not that im claiming to have those numbers, but i can speak for the dT, the true cpu power output is what's highly questionable. i just like to use those C/W's to compare my blocks on my system. i'd say this temp drop is a success! thanx #Rotor.

I always wondered one thing about "#rotor" blocks -
why the pins in the top?
They do nothing for heat transfer, really.
If things are too restrictive without them, wouldnt it be better to use a thicker copper baseplate with deeper holes? IT just strikes me as strange.

yes, the top is just for more flow and making deeper holes in thicker copper would be better. but it'll be harder to make because the deeper you have to drill into copper, the more chance of the bit getting stuck. then how are you gonna make the channels with a dremel wheel in a block that deep? maybe you can try using a big cutting wheel, such as for an air compressor, but how will you get it to cut the channels all the way up to the walls (or anywhere near them for that matter)?

Strange yes, but fear not, method to the madness used to be my motto.... now it's just madness.... :D

Maxim point's them out, it's all about manufacture-ability..... no use in theoretically having the perfect block, when in practice it's impossible to make, now is there :) Remember that we are severally limited by the tools to our disposal, not to mention those cut-off disks are actually damn expensive, considering that they are very much a consumable in the manufacturing process..

well, i gotta ask then, if i had 1/4" thick copper could i use only a bottom plate w/ a lexan top? i know the rotor design is fairly free-flowing, so would i be ok cutting flow back like that? "OT" nice lookin' block you got there. :cool:

of course, it makes sense from a perspective of ease of manufacture.
I was just thinking performance wise.
Anyways, i must say, looks like a nice block - good job maxim!

it took you 9 HOURS!!???!?!?!?! i did all 3 of mine in less then that
omg how slow are you drilling, like 1 mm a minute?? i just drive the thing on down. i think thats the problem with my shiti ass blocks...

oops srry i forgot u did 8 drills... how fast did u make each hole?

for sure you can...

I don't know if it would increase performance, but i would put some AS3 Thermal Adhesive between the top and bottom pins to help heat transfer between them. It SHOULD make the top pins help out to cool the bottom pins, at least a bit.
Well its just a thought anyway, i don't know if it works irl (ie. the thermal adhesive dissolves in the warm water).

Actually water makes a better TIM than AS3 according to tests at Dan's Data... in fact even tooth paste is. Until all the water evaporates that is, then they suck. Not something you have to worry about in a WB.

Well ... I'm not sure about the article, but my speculation is that the evaporation is what cooled it so well ... you'll have none of that shenanigans (boiling) inside a waterblock unless you make a major mistake ;)

Water is not a bad TIM , not the best, but much closer to the " best" side, than to the "worst" side of things. Also consider the fact that the gaps between the pin-tops, are virtually nonexistent, though not entirely, and we know that a TIM joint's thermal transfer is inversely proportional to its length.... (thickness) correct???? :)

for argument sake let's pull some imaginary numbers to illustrate the concept... say water has a number of 0.0005, which is representative of its thermal transfer, and that needs to be as big a number as possible... obviously not good as it stands now...:eek:

BUT the distance between the two surfaces from where the heat needs to travel, is 0.000001m...

now 0.0005/0.000001= 500.

again highly imaginary numbers, only for illustration. The smaller the gap, the lesser negative effect of the TIM not being Diamond. :)
In a waterblock, you can hardly ask for a better tim than Water....:D

maxim,

The best luck I've had at drilling holes in copper, whether starting with the final bit size or working up, is to attack the copper aggresively. Meaning fairly high feed rate AFTER you get the hole started.

As you pointed out, this keeps everything cooler. Why ? you may ask.

Well, as your bit cuts deeper, you have the cutting edge of your bit making less repeated contact with the same local area. In other words it's progressing DOWN into the copper and the heat is being carried away with your shavings.

If you aggressively cut into the copper about 1/16" to 1/8" at a time. You don't need to have oil or anything. Cut it dry.

Smaller pieces of copper will retain more heat, but that's my experience with ½" thick 2" x 3" pieces.

MMZ_TimeLord, you are exactly right, also the bit's side is making a lot of contact with the walls, which adds to the heat produced. after drilling the first 2-3 plates i discovered that when i stab the copper, the bit does not heat up and get stuck. however, with my press it is dangerous to do so. i have snapped several thinner bits like that and got bigger ones stuck. the thing is just not good in construction quality at all. would have probably worked for wood flawlessly, but copper is a diff story. what i had to do is find a balance between how hard i push on the bit, how fast i move it and how many holes i can drill at one run before taking a minute break. im not complaining though, this way i learned on a weak machine, so if i ever go to a better one i will not simply rely on the machine to do my work, but instead know how to use it to its full potential:)

When I made a #rotor block I used about 1.5 "heavy duty" cutting wheels. That didn't seem like a lot, am I doing something wrong? I did it fairly fast ( when I touched it to rotate it, I got a nice burn on my fingers and threw the block across the room :) ). It took about 15 minutes and it turned out looking nice.

i have a mini circular saw on one of my cutting disks. looks exactly as a circular saw but is about the size of a cut off disk and is attached to the pole to go into my dremel. whats more im sure dremel made it but i cant find it anywhere on their site...

Nice job, Maxim!
I like the lapping.
A $90 drill press... Wooow... I have a less-than-$25 drill stand and an impact drill. I wore out my first drill (not the drill bit; the power drill) last sunday, it just died on me, but the very same evening I found a new impact drill for less than $12 at the local store.
With a little practice, impact drills are great for making dimpled base plates. ;)
A drill press, You lucky one...
regards
Mikael S.