Question on waterblock design

When making a double barrel waterblock, it won't cause problems to just Y the line before and then reverse Y it back into one line after the waterblock, like this...

3/8"->2x 3/8"->Waterblock->2x 3/8"->3/8"


...will it?


Also, what's the internal diameter of 3/8", 1/4"npt barbs?

to my understanding it always reduces flow rate when Y'ing, so i would avoid it. if you've already calculated the reduced flow rate into your design then i guess that wouldn't be a problem. i would doubt that the design of the waterblock would be so superior though to compensate for decrease in efficiency of flow rate. actually, wouldnt the only benefit of having a double barrelled block come from running two seperate loops altogether? to ask the same thing a different way, wouldnt the advantage of a double barrelled block be that it can increase the overall volume of water/flow rate through the block? i couldnt think of where there would be another advantage.

as for the second question, i was under the impression that the diameter specs of the tubing always referred to ID, but maybe im wrong

when you split a 3/8" tube into 2x3/8" tubes each of the 2 tubes will get half the flowrate of the original 3/8" tube. its better to split it into 2 smaller size tubes so you can get a good flowrate through the block. like split a 1/2" into 2x3/8'" tubes. and the inner diameter of 3/8" 1/4ntp barbs is 1/4" i think.

in ideal conditions (assuming connectors had no effect on flow rates) then if you use a 1/2" ID tube and split it into two then each tube it is split into will have half the flow of the original. you will get the same flow rate through the block as though you had a single 1/2" tube going in - the water will just be moving slower in two paths instead of faster in one path. the overall flowrate of water passing through the block is the same, and when discussing flowrate, this is whats important, overall flow is what counts. you can decide if there is a benefit to running it this way, but that is what happens in theory. (realistically you are going to be hurting flow rate further from seperating the tube and the connectors.) if Y'ing of a single loop is absolutely necessary then it would be best for your tube before and after the split to be wider than that which is in your split. but overall i see no advantage to the double barrel design with a single loop. did you have one in mind, maybe im forgetting something?

if you are gonna use y connectors i suggest using connectors that have the same inner diameter *** your tubing so the y's dont cause flow resistance. so if you are gonna use 3/8" tubing get 1/2" y's

SHOTGUN!! you can use 2 smaller pumps or one large pump into a larger "Y" that knocks the twin lines down a size

Actually Thinking it over, Maybe a single 1/2" line in then is split in the waterblock and comes out 2 3/8" lines Leaves me in a real nice position if I want to add a gpu and chipset cooler later also. Then combine the two 3/8" into a 1/2"

Is the flow of a 1/2" equal to the flow of two 3/8"?

grim, is it possible to get the smaller tubing over the larger y's? if so that isnt a bad solution. nice quote in sig by the way. id still like to know what the advantage of the double barrels is in theory? i just dont see one, it seems like it will only cause flow restriction unless double loops are run. :confused

the only advantages gained with current block designs (for now) it seems are reaped through properly manipulating turbulence and increasing surface area. as far as flow rate you cant get more flow rate without a stronger pump or less restricing waterblock. the double barrel design would get more water moving through the block at one time and it could improve overall flow rate only if two loops were run i think.

The waterblock would be designed so that it it would have alot of dead unmoving water if A double barrel technique werent used... And I didn't want to bother with two pumps to begin with.

The designed mentioned in my last post looks like it would work rather well, but it would make designing the mount a big hassel.


That bulletproof plastic-like stuff that doesn't bend or stretch.... what's it called again, how much does it cost, where can it be bought, and What type of holecutter would you need for it? (what material)

yeah you can get tubing over larger fittings. you just have to heat the tubing up and soping the barb helps too. the double barrel design wouldnt cause flow restriction its would minimize it because there are no turns or mazes for the water to flow through.

glad you like my sig.

i think ive made my thoughts fairly clear and i hope im not ticking you off. i just want to help by constructively criticizing the block while its in its design stage rather than once you already put work into milling it. i agree two pumps arent really worth bothering with. i think direct series is almost always the best way to go and parallel only detracts from efficiency, but i dont think i have any more to really add that is of any help right now.

The problem is this. Im not milling it. This is a "cheap *******" block.

It's a solid copper heatsink, microfinned, two banks with a break in the center (where the mounting clip was) Lemme see if I can illustrate my plan...





Horribly drawn (i never use paint) and not anywhere near scale, but you get the idea.

I would Join the 3/8's using a 1/2 Y, of course I NEED to know the ID of a 1/2" barb first if anyone can answer that.

Oh and I'd cover the whole thing (except bottom) with 1mm copper plates. Whats the best, (most reliable) way to do the seams?

1/2" OD barbs have a 3/8" ID

So a 1/2" has slightly more flow than 2 3/8"?

Damn, oh well, I guess I speed up leaving the waterblock, slow down at the Y and have a little less gph. Not a big deal.