Sandcrawler project

[artoodeeto]

woo hoo! just got the call from the local graphaids, the plaster of paris I ordered is in. Now to get some mineral oil, and I will become a mad mold-making machine! ok. sort of. I'll post pics of the other piece I'm sculpting soon, hope to have it done before the weekend so I can mold/cast the first batch on Saturday

[artoodeeto]

here's the piece that's going to be the main mechanical unit on the rear wall (there'll be 2 copies of it, and while I pictured it horizontally, it'll be positioned vertically). The basic form is done, and it was surprisingly hard to make it symmetrical by hand. But I (mostly) got it, so tonight it'll be on to detail work, then molding/casting on the weekend, and once it's on the crawler, I'll add extra model pieces for more detail. I cut the posterboard card it's on right now to fit vertically in the space on the crawler, so I wouldn't have to worry about potential misfits/misalignments.

right-side up:

and upside down:

[Loki]

Great handcraft man!

[artoodeeto]

Nearly done with this piece! It's taken far longer than I thought it would to sculpt. I just need to smooth it out, possibly add a couple more recessed or raised areas, and then texture in some detail. After that, I can mold it and cast it and get back to assembly of the case.

Now for some innards. My CPU fan blows hot air right back at the PSU. So I thought, ok, I'll get a dryer hose (thx for the tip billygoat!) and clamp one end of the hose to the heatsink, then route the other end of the hose up to one of the exhaust fans. Didn't work - the hose diameter sadly was 0.5" too small (4"; the heatsink diameter is about 4.5"). So I thought ok, I'll try sticking a funnel-shaped piece of paper on there, force the air up and away from the PSU, toward the exhaust fan. It looks terrible, and only sort of works. My next idea is to turn the CPU heatsink around so the fan's blowing the other way, and I'll probably retain the paper funnel to force air to yet another, bigger, exhaust fan. Any other advice is greatly appreciated - there's no ideal solution without gutting and re-doing the inside, but there may be better solutions than what I've come up with so far.

[Airbozo]

RE: ductwork.

Since the metal stuff may not work, check the plumbing area at your local HW shop and look for drainage pipe. They have some 90 degree bends that may work.

[artoodeeto]

Thanks, I did look at some of the plumbing stuff too - the real problem is that if the pipe is wide enough, 4.5" or 5", any kind of 90 degree bend simply doesn't fit in the space available. Even the foil-coated spring duct that I got doesn't really fit well. the situation won't change if/when I flip the fan around, because then instead of heatsinks and such blocking the duct, the memory chips will block it. This wasn't a problem in the past because my older dual core AMD didn't generate nearly as much heat as the quad core does...oh well. I'm hoping flipping it will force most of the hot air to the bigger exhaust fan, and thus force more out of the case where it won't superheat the PSU. We'll see...

[x88x]

One thing that might work is to use a 5" to 3" restricter right off the HS/F; it would increase the pressure, but you should be able to get the same airflow if you do it right, maybe throw an 80mm fan inline in the 3" portion to boost it. I think you should be able to get the desired affect as long as the 80mm fan has at least the cfm rating as the 120mm in the HS/F.

[msmrx57]

Thin aluminum to form an adapter for the ducting to hook to?

[artoodeeto]

good ideas both - time for another trip to home depot to see if they have anything that'll work. As for exhaust fan size, in its current orientation it'd go to an 80mm fan; if I were to flip the H/S around it'd go to a 120mm fan, but because of the RAM chips there's zero room for a hose (even paper). So if I do that, I have to hope that the high CFM of the 120mm is enough to vent the 92mm.
In its current orientation, with the paper funnel, the 80mm fan covered about half of the top opening, but the paper didn't go quite all the way up to the fan, so I think a lot of warm air escaped back to where the PSU is.
The Zalman 9500 fan size is 92mm, so it's probably got a slightly higher CFM than the 80mm fan. Maybe what I'll try and do is since I have two 80mm exhaust fans side by side, and my paper funnel only got over to one of them, I'll try and do the tube maybe with a flare-out at the end so both 80mm fans are exhausting the warm air. I'd rather have negative pressure between the CPU fan and the exhaust fans than positive pressure. I'd probably still use paper for at least the flare-out for a couple reasons: it doesn't conduct electricity, which is an important consideration because I'll likely have to mush it in place, it won't tear as easily as aluminum foil, and is much more pliable than even thin sheet aluminum (not to mention cheaper if I screw up ) It won't look great of course, but hey, with the top on it won't really be visible.
But as a first step I'll definitely look at Home Depot and see if they've got anything that might work. I just wish there was a little more space...

[x88x]

You could also try thin cardboard or posterboard instead of paper. It would be stronger but still very pliable and cheap.