Custom (very) Quark esc heatsink...

[BrianG]

The whole thing is held by the sticky thermal pad at the bottom. When I removed mine, I took a small flat-bladed screwdriver and gently pried the heatspreader off the case. Then, even more carefully, pried the heatspreader off the FETs. Gotta be careful here as the casing on the FETs can break.

You could take it completely out of the case, attach a larger heatsink, wrap the rest of it in heatshink, and then cut a hole for the heatsink like how the BK Warriors are built. But, having a nice metal enclosure is one of the nice things about the quark as it helps to protect everything else.

Oh, and those pins connecting the two boards are soldered in. They are very close to some other surface mount devices so be careful if you decide to desolder the pins! Those nearby surface mount parts can easily be damaged by heat and there goes your $280 controller!

[zeropointbug]

Hey, yes, like Brian said. You just have to get a small screw driver where the battery power in wires come in, and put moderate pressure up, it should start crackling and start to come off.

THen what I did to take the heatspreader off the FET's, was use the plastic end piece as a leverage spot, and put the screw driver tip just under the pad (where there are no FET's) and do the same thing. However, it's stuck on the FET's better than it is to the case, so just constant pressure up with leverage on the screw driver, and it should slowly start crackling and lift off.

Would you mind posting pics of the heatsinks you have? I'm curious what you have.

hmm and where's the part that's not getting a good thermal contact? I just kinda felt like jumping into this when I woke up.. 3mm shim's needed where? because it all seems like it's got good contacts between the fets and the bottom of the case.. i don't see it moving anywhere.. debating if I should just throw a heatsink on it, and see if it thermals, and worry about dissecting it later, if problems arise? I tried w/ a small flathead, but the dozen or so flatheads that are small enough, aren't long enough to reach the metal shim.. about 1mm too short =\

here's the heatsinks I've got at home.. there's an AMD Athlon stock HS on the left, and the rest are either older CPU heatsinks, or northbridge heatsinks.


and here's an old hard drive with some heatsinks.. I just think it's funny to have heatsinks on a 5400rpm hard drive lol


then i've got some old motherboards and videocards (tnt2's and voodoo3's) out in the garage, with a wide array of heatsinks.. if I need..
at my work, we've got alot of old computers, w/ a very diverse selection of heatsinks.. you should see how big the heatsinks are on some of the older servers.. oct-cpu servers and such have 6"x6"x4" or so heatsinks :)

[zeropointbug]

Hmmm, well that green one looks like a great one to use! With a little fan if you want?

The Athlon heatsink is kinda tall, and too heavy, IMO. Although, would work very well!

You've gotta have a small screw driver that can do this!? :032: :005:

I assure you, the FET's are not well thermally coupled to the case at all! First, the thermal pads are crap, not for high output applications, and there are two of these to go through. Second, where it attaches to the case, it's only touching along the two outer edges, about 1/4 each side. It just can't escape.

BTW, how come you bent down the side of your Quark case?! :002:

haha prying.. it's straight again.. if I did it again though, it'd most likely snap off.

i'll take it with me to work tommorow, and get it apart.. the AMD HSF is pretty big.. but I'm thinking about securing it to the controller.. and then have the fan on the side of the HS... and mount the HS on it's side, behind the steering servo, in front of one of the battery packs.. we'll find out how well that works in a few days i spose.. if not, the green one's the best bet.. I really need to get/make a 12V mod, so my fans run at 12v.. if you notice the deans connector on the UBEC, i've got one of my 12v fans running on 6v right now.. but it still pushes more air than the fans on the novak units lol

Originally Posted by Patrick

The loaded speed for a 7xl is 2145 I think, so 2145 x 16.5 = 35400rpm
The unloaded speed is 2382, so 2382 x 16.5 = 39300rpm

Hope this heatsink turns out well for you though. I've recently damged a second Quark with over heating problems. I use the heatsink from rc-monster, one 40mm fan, one 3'' fan and I don't think I was doing anything other the top with it setup wise, yet it still can't do a 5 minute race on 14 cells.

Does this happen alot?? I was looking at a Quark and NEU motor combo but if it can't do 4S lipo's for more than 5 minutes I don't want to waste my money. will the Quark last the runtime of the batts in an E-maxx?

[GriffinRU]

Originally Posted by zeropointbug

Well, to be honest, MOST heatsinks for CPU nowadays are just designs, that's all they are. Lot's just looking cool, decent cooling capabilities, nothing great. Most heatsink design is coming from PC industry now.

Like i said, heatsink design is tricky, as there are several ways you can make it perform: such as LOT'S of airflow, NOISY, and guaranteed to work, with moderate fin count. OR another extreme, like these large tower heatsinks, using heatpies densely around the CPU, then efficiently transferring the heat as vapor to a large set of fins. This method works amazingly well, and better uses a given surface area of fins, than a simple heatspreader, fins design.

What kind of experiment did you do?

Problems can be found here under "Limitations" and at the bottom check "See also" and "External Links" heat-pipe selection guide

As far experiment - you know the answer, right :)

[BrianG]

I'm running the Quark on 4s with a 2600kv Neu on my buggy and it runs cool with a simple small heatsink (no internal mods yet). The internal mod just makes it run that much cooler.

And just to clarify about the way the internal pads work and what needs to be done to replace the existing heat spreader:



The drawing above isn't exactly to scale, but you get the idea...

The stock heat spreader is 2mm thick and each pad is 0.5mm thick. This thickness is needed so the capacitors clear the case. Once you remove the pads, there isn't enough thickness for the caps since the epoxy is very thin (practically 0mm). So, a new spreader that is 1/8" thick works perfectly.

[zeropointbug]

NICE work Brian! Very easy to understand.

The thermal pads and the slab, I measured 2.85mm together with a digital caliper. But I suppose 3.175mm won't hurt...

Do you know of any angle copper or aluminum that could be used to connect the top and bottom FET's together?

I'm almost tempted to make a water block slabs for the thing! And put a rad out front of the vehicle, now that would be the ultimate! :027:

I am just trying to figure out a way to keep this 540 7Xl cool! I should have just got the smooth can version and made my own water jacket for it. Then the entire vehicle would be water cooled.

Does anyone know how I could make the fins on the 540C can into a water jacket?

[BrianG]

Thanks! I thought it would be easier to explain with pictures. Unfortunately, I didn't take pictures of the process when I did it. Mine measured just under 3mm (like 2.97 IIRC) - maybe the pads weren't as compressed on mine. Dunno. But 1/8" works well.

I didn't touch the middle FETs since I didn't even have any idea how I was going to couple that heatspreader to the case. I figure the better cooling on the other side would help leach the heat away from the whole board improving cooling all around.

For your water jacket, just wrap some copper tubing around the fins. :)

[zeropointbug]

GriffinRU, I know all the limitations about heatpipes...

They really do have to be tuned to a specific operating temps, and ambient temps.

I know this first hand.... frozen CPU.... i've done this before in the winter when it's -35C outside, with the PC case in the window, the CPU will get to below O temps, by doing this, you can get VERY high overclocking levels! Last year I took a Pentium 4 3.2 Northwood (130nm) to a sky high 4.25ghz! That was with a solid copper heatsink though.

THIS year, with my new PC with a large tower heatsink (Noctua NH-120) I did a cold window test, although only -15C, and the initial temps went down to about 5C, after a few mins of running the temps started to go up and up, until it hit 55C... hotter than what it gets at room temp! So they are definately sensitive to ambient temps. My guess is that the vapor just froze up and physically BLOCKED the vapor chamber.

I guess it all depends on the pressure of the working fluid for a certain temp range. Diameter, and length have to do with energy transfer.

Every couple months, manufacturers come out with new heatsinks, most all the new ones are heatpipe ones. The new Thermalright Ultra-120, and their IFX-14. The IFX uses biggest 8mm heatpipes, and uses 4.

If you had the room, the more heatpipes you can fit at the heat source and lower vaporizing temps the better, and evenly spacing the pipes into a fin radiator.

It's all in the design!

[BrianG]

LOL, it's in the design of the CPU! Make a more efficient CPU and you won't need those exotic cooling solution. ;)

[GriffinRU]

Originally Posted by zeropointbug

GriffinRU, I know all the limitations about heatpipes...

They really do have to be tuned to a specific operating temps, and ambient temps.

I know this first hand.... frozen CPU.... i've done this before in the winter when it's -35C outside, with the PC case in the window, the CPU will get to below O temps, by doing this, you can get VERY high overclocking levels! Last year I took a Pentium 4 3.2 Northwood (130nm) to a sky high 4.25ghz! That was with a solid copper heatsink though.

THIS year, with my new PC with a large tower heatsink (Noctua NH-120) I did a cold window test, although only -15C, and the initial temps went down to about 5C, after a few mins of running the temps started to go up and up, until it hit 55C... hotter than what it gets at room temp! So they are definately sensitive to ambient temps. My guess is that the vapor just froze up and physically BLOCKED the vapor chamber.

I guess it all depends on the pressure of the working fluid for a certain temp range. Diameter, and length have to do with energy transfer.

Every couple months, manufacturers come out with new heatsinks, most all the new ones are heatpipe ones. The new Thermalright Ultra-120, and their IFX-14. The IFX uses biggest 8mm heatpipes, and uses 4.

If you had the room, the more heatpipes you can fit at the heat source and lower vaporizing temps the better, and evenly spacing the pipes into a fin radiator.

It's all in the design!

Dude have you tried liquid nitrogen cheap and efficient, you will be surprised what you can do with logic in liquid nitrogen :)

The only problem what is good for CPU is not the same for buggy running at open, not in air-conditioning environment...

I am sorry but I think we done here. Information was for everyone do not take it personal.

[zeropointbug]

Originally Posted by BrianG

LOL, it's in the design of the CPU! Make a more efficient CPU and you won't need those exotic cooling solution. ;)

Exactly! The record so far was the Pentium D 840, this thing was a SPACE HEATER! :005: :026:

The new Core 2 Duo's are quite a reduction in heat output! And doubling performance at the same time.

But a better heatsink, means higher clock speeds, IF you overclock, but enough of that talk...


"I am sorry but I think we done here. Information was for everyone do not take it personal."

Who is taking anything personal?

[GriffinRU]

Looking on all this mighty heatsinks I am thinking how much power dissipates on Quark?

Lets say 7XL draws 50A continuously, so at 0.00036Ohms at 25C power loss should be 0.9W
Next say at 100C derating factors bring us to 3 times up, so 0.00036*3=0.00108 - power loss now 2.7W

To get even 10W requires Rdon to be at 0.004Ohm which is 11.1 times higher then at 25C.

So, is the ESC efficiency so low or there is something else?