Water-Cooled Borg Cube, Part 3:

Water Block, Continued

aka Bob is assimilated by his Borg Cube...

Okay, we're getting close.

Just drilled and tapped the holes for the water barbs. Don't they look nice in chrome? I sure was glad for the 1/2" ratchet--the acrylic was pretty tough to cut through.

I wanted to make a divider to channel the flow so it wouldn't all just go straight between the barbs. This plastic packaging from my Digital Doc should do nicely!

I'm going to place this piece down in the pins diagonally between the barbs. Water leaving the barb has to circulate left and right around the central obstruction.

See where the divider goes?

Now we perform a trick a friend taught me. To avoid the glue going everywhere, I apply masking tape to the top and bottom. The block rests nicely on the bolts, so I can just apply the goop around the base and then squeeze it shut, being careful not to squeeze to hard that I lose all my goop!

The goops in, the two halves are squeezed shut, and the masking tape is peeled before the glue dries. Voila! Note how the goop rides up on the pins a bit. This was actually quite intentional. I put a lot of goop inside near the pins in hopes of getting this type of effect and maximizing my chances of this thing sealing well.

Fixing the Leaks

Leak testing rig. Trusty Plumber's Goop stands ready nearby, along with a bucket for total meltdowns!

After giving the goop 24 hours, I hooked the block up in my test rig to look for leaks. Bad news! There were several, all associated with the bolt holes. Note to others: If I had it to do over again, I would've used a lot more goop around the edges and made damn sure there was no possibility for a leak! Now I have to try to fix the leaks from the outside, which is harder. Basically, I'm resorting to using the screws to deliver goop to the insides of the holes. The good news is goop seems to readily form a thin layer, at least on my fingers. We'll see how well it goes. If worst comes to worst, I'll have to tear the top off and try again.

Done. No leaks!

A couple of tips here. First, don't assume your fixes worked, test again after each fix. I found that as a fixed each leak, new ones would show up, presumably due to flow patterns and pressures in the blocks. Once I got all the leaks around the holes sealed, one of the two barbs started to sweat slightly. So, pull the barb, apply Goop to threads, and voila! No more leaks. Second tip, is to test in increments. First fix all the leaks by just letting water stand in the block. No need to pump, it'll just make a bigger mess. Then, crank up the pump. Fix those leaks. A bucket is handy for catching the mess when you take the hoses off after each time. Last, add Water Wetter. This is the stuff that gives so many systems a slightly pinkish tinge. It lowers the water viscosity and encourages better cooling performance. Lower viscosity will also run through holes more easily, so keep looking for leaks after adding some. Lastly, Goop can dry faster than you'd think, I found out. Turns out a heat gun will encourage it quite a bit. Thin layers, such as you use for fixing leaks, also dry pretty fast. I was able to get two leak fix cycles a day with these techniques.

Okay, I'm declaring this water block DONE!

Let's Install the Water Block!

 
All material 2001-2006, Robert W. Warfield.