Quark thermal issue?
 

If I run my truck on track after while it suddenly stops.

On Quark YELLOW led is on (i have yellow for forward and green for reverse thanks to futaba 3PM). I have to hit reverse/forward and the truck will start to move again. Quark case has about 113 degrees F (45 C)

Is it a thermal issue? It looks like.

I have heatsink w/ fan on it.

How long have you had your Quark? It is common knowledge now that the outside temp of the Quark has nothing to do with inside temp. :005:

The thermal interface of the FET's to the case is poor (at best), it could very well be thermally when the outside is only 45C yes. The thermal pad in yours could be coming loose, and getting dirt inside it (it's only touching about half the thermal pad to case).

Well i know the temp difference can be huge but cannot measure it inside :)

I was trying to disassemble it to put there better thermal pad or grease but it holds like crazy

Its quite disappointing as I run motor that does not have so high currect draw and only 16cells

If the thermal pad isn't making good contact, your internals will be much hotter than the external case. Taking it apart is not difficult; just use a small flat-bladed screwdriver and GENTLY pry the metal slab from the case. Then, you can gently pull the slab off the FETs.

I still don't know what happens when the Quark goes into:

-'safe mode'

-LVC

-and a thermal shutdown

I we knew this, then we could better trouble-shoot the Quark.

I dont like the word "Gently"

when I try it something usually breaks :)

guess i have no other choice

I am finally happy with my maxx and this is the last issue

That was fun. while removing the top cover the button fell off as well the black thingie next to it broke on of its leads. Thank god i got new soldering station yesterday as my old $5 60W soldering iron would be useless. :027:

Now I need to choose best thermal adhesive/tape.

I have Thermattach T411 tape or Artic Ceramique paste or some cheap Thermal Epoxy

uh oh

That doesn't sound good at all! I should mentioned that you need to pop off the little lense on the top cover that shows the LED's, it does it a surface mount chip, i don't know what. what was it? are you good at soldering?

I don't get how the button can come of though, it's not sticking out anywhere? :032: :002:

Need pics! Doesnt sound too good though- broken leg of a chip can be patched up with some good solder probably, just go easy so you dont solder all the legs together etc.

I guess I am getting good in soldering. I fixed it and everything works without any problems.

I did not have this problem with cover removing on my previous quark (died and got this as replacement)

So now to the thermal adhesive decision. any suggestion is welcome.

Arctic Silver "Arctic Alumina" thermal adhesive is the stuff you want if it's going on a chip. It's not electrically conductive or capacitive if the stuff oozes out of the sides when you press the heatsink on.

Regular Arctic Silver thermal adhesive is said to be capacitive, so it would be better to use on the outside of the case.

So should I remove the bottom heatspreader from the FETS? It would need tons of the adhesive

What about the top FETS? I dont like the idea of just putting the adhesive everywhere or is it needed?

The middle heatspreader is kind of a pain to get to without seperating both boards. I just leave the middle on alone. But, yeah, the bottom heatspreader should be removed, and actually replaced. When you replace the thermal pads (on each side of the bottom heatspreader) with epoxy, you actually lose almost 1mm of thickness (yeah, they're that thick). See the image below for more of a pictoral explanation:

http://scriptasylum.com/forumpics/quark_mod.gif

It's not hard to do and well worth it IMO. I just had the thermal pad let go on my Quark recently and was floating around in the case.

By the way, you shouldn't need a lot of adhesive. It's supposed to be a very thin layer.

Here are some instructions to open the lid on the Quark just in case others are trying to open their case as welll:

Best way to remove the lid is to stick a small sharp screwdiver above the "R" on the plastic lid where it says "MONSTER" (there is a small notch cut out in that spot you will see) gently pry the side of the aluminum case outward just enough to then pop the plastic lid upward. Works very well.

Yeah, DON'T try to slide the cover off. I did this on my first Quark and broke off a device right near the button! Luckily, I was able to solder it back on...