they would work fine. What i would do though, is put the heatsink on the bottom, and mount the fans from the side. mainly the heat comes from the bottom and the one side of the quark (opposite side that the program button is on).

That fan uses 12v. And you realize there are blue LEDs on the fan right? Personally, I'd just go with an adequate heatsink and ditch the fans, but that's just me...

True. 12v won't pull the air like it should. Find some 5v fans. 12v will require too much v and not blow enough as they are not getting adequate voltage. If you use 5v, you'll actually be pushing more air with those. IMO, i would use fans! especially if it's hot where you are.

I didnt even notice they were 12v. I agree... look for somw 5v fans. The heat sinks on those would be prfect though. The Quark is 37mm X 74mm. 2 40X40 heatsinks will cover the entire back surface of the controller. The 5v fans metalman linked were perfect. I founs some on ebay, but they were more expensive than metalmans.

If you can, run fans. I like the insurance of a nice cool esc. I'm sure you would be fine w/ no fan if you can position it so you get some decent airflow over the heatsink.

I'm going to run two 30mm fans, which should be nice. heat sinks are hard to find that look and work nice. Some are spendy. If the bottom of the heatsink is thicker, it'll work the best and you may not need fans at all. Or, get the ones you were looking at and then just take the fans off, sell them on ebay, and buy the other ones.

thank you for the advice. I bought the heatsinks for the pre-threaded holes for fans. I have a couple of 5v fans at home i'm goin gto use. :027:

That 2nd one down is a pretty great setup. I wish I would have used 2 of those for my controller. I would use some thermal epoxy and just permantly bond them to the bottom of the Quark.

Are you guys using 5 volt fans on 14.8 volts or off the bec on 6 volts? I use my 12v fans directly off the batts (14.8 volts).

5v off of the 6v BEC

Hey dudes... why do you think 12v fans are bad or can move some good air???

I have run both 5v and 12v. Some fans are definitely better than others... some are duds and some work great.

I have always run 12v fans on whatever the pack is. So a 4s lipo would really make a 12v fan boogey I would think.

BTW, when I get a 125b I think I will try to stick it to the alum chassis and see how that does as a heat sink... no added weight, clutter, etc... it's a free built-in sink with lots of airflow under the vehicle. Anyone try that with a Quark? (buggy/truggy)

On 5s or 6s lipo, you will boogy the blades right off of the fan.:005:

Not to mention the fan motor will burn up in no time. On 5V off the BEC you can run whatever battery you want and it doesn't matter.

12V fans are fine if you are running only 12 cells.

Hi, I am running a 12 volts 6x6 fan with 5S lipo without problems since a month or
two.

Daniele

I hope you mean 60x60mm - 6x6 would make a hovercraft...

I am running 2 12v fans on my quark heatsink - I got 35 mins of solid run time and its still holding - but boy does she sing when i plug her into the 5S....

haha,
sure, here we use to call them the 25x25, the 3x3, 4x4 and so on :)

Ciao,
Daniele

Walter, Mike was saying that running 12v fans from the receiver would not be as effective as running say...5v fans?

Yea, he isn't running them from the reciever, but off the batteries.

I do believe that Darren did that with great success on his Lightning Stadium.

Mounting to the chassis should work fine as long as the surface is VERY flat, free of scratches/pits/bumps, and unfinished (painted, anodized, etc). The only thing that makes me leery is that there is no padding to protect the ESC against jarring. That is why I prefer to add a heatsink to the ESC and then mount that on some type of foam padding at least 1/8" thick.

I can tell you that the fans probably wont last as long at 21 volts than at 12 - but i can tell you this - they move some air :005: - i also have 5 volt fans - Maybe ill use a 12 volt and a 5 volt on my heatsink - Easy enough to do -I had my quark mounted to my custom rear plate with a heatsink mounted underneath and i had some problems with thermaling - i changed my design - used my heatsink and recessed my quark into the back - mounted with thermal paste and 2 fans. I ran 7400mah 5S - thru her yesterday - and i was hard on the trigger trying to get her as hot as i could - she got warm - but it didnt thermal - even after 35 mins of racing on the track. It worked awesome - im redesigning my heatsink to see if i can improve the performance - Overall im happy - For now anyway:cool:

For some reason walter i thought you were running the mgm. Wow, that's too bad about the thermalling probs you had. Good to hear that you got it to go now though. I may add and extra hunk of aluminum to mine as well. i have a huge piece that the quark can fit on, so i will be a dremmeling fool! LOL, but i should be fine with the set up. Those neu's must be awesome motors!

Yea - the mgm is on the centerdiff revo - didnt break her out that day

Ah yes, that's right. she was looking too pretty! LOL....didn't want to get her dirty....hehe, how does it run?

slow - very slow ;)

You have a slow truck? I don't believe you! What are you running for a motor? LMT?

1950

Well, i guess for you that might be slow! LOL But to me, if i could get my hands on one!!!!! ZOOM ZOOM! I'm running a 9xl now.....I don't think i would want to race you with that! Maybe on a track, but not on the open street!~

For those of you who have burned up speed controllers, I have two questions:

1) How do you burn up an ESC if it has thermal overload protection.

2) How many cells/volts are you running to have such problems... I'm especially interested in those using the Quark 125 Monster ESC. I'm only using 14.8V (4 Lipo cells in series=4s).
OldSoldier

I haven't burned one up (yet), but even though FETs by nature are somewhat self-regulating, they do have the potential to instantly pass huge amounts of current. This current can blow an FET in microseconds. You would need current limiting to prevent that. Thermal protections are designed to prevent a user from continuously running hot until parts melt or desolder themselves. However, thermal measurement is too slow to protect against instantaneous high currents. It's really a function of time.

I fried a 9918...I think it was water though :002:... However, I'm not sure since they replaced it for free...Surely the woulda found that water was the cause :032:.

How hot is too hot for motor and how hot is too hot for speed control? I have a temp gun for my nitro cars that I can use to check the temp of the motor can and speed control.

My motor can got pretty hot one day recently but it was near 100 degrees outside.

I think it is like 180 f for motor is to hot. In the neighborhood of 170 or so is thermal for esc.

I fried a few escs. One was 7020 on 18 cells. I think had the motor over geared. Fried a 9920 on 6s lipo. Don't know what happened. Fried a quark 80b on 1930 6s lipo. Had a start up problem and fried during this process. I think some times it is the vibration gets to the electronics in them.

from my experiences - 140 or 150 on the Quark 125 speed controller ( by where the motor wires come out of the controller ) will send you into stop and go land...:035:.

I just tried it yesterday on my Quark 80B and Feigao 9L. Both were at about 155 degrees when I went into thermal shutdown... I'm using outlaw 20/66 gearing so I figured it would get hot.
OldSoldier

Try dropping a few teeth and see if that helps.

20 66 gearin on a 9L. I would expect a thermal. Especially if you running emaxx diffs.

I just dropped to 18/66 and it was still thermaling. I dropped to 16/66 and it was a little better, but still almost 140. I didn't have any pinion gears between 16 and 12, so now I'm at 12/66 and it stays below 125 degrees. I'll take another look through my parts boxes and see if I can come up with a 14 or 15-tooth pinion gear.

CoolHand... I'm intrigued by your comment about the Traxxas stock diffs...I was thinking about getting the FastLane combo Diff/bulkheads with advertised 1/8th buggy gears. Is that what you recommend?

OldSoldier

You have to get the Hybrids, not the combos. The combos are for stock gears. But yes, the FLM hybrids, with Some HB Lightning diffs is definately the way to go.

The flm hybirds with the buggy diffs are alot stronger than the stock ones. The gear ratio is lower as well. 3.31 to 2.87. The size of your tires makes a difference as well. If you run some big heavy tires( like big joes) or some smaller tires like ( crime fighters) effects the heat as well.

Anyone find out the voltage on the Quark yet? on the fet's?

which kind of thermal adhesive are you guys using for the heatsink. I had some artic silver 5 laying around and used it, but i have to use zip ties to keep the heatsink/esc in place.

Thermal Epoxy
 

See attached.